Aap bilkul sahi keh rahe hain!

Maine koshish ki thi Hindi terms include karne ki, lekin shayad
woh poori tarah Hinglish style mein nahi tha jaisa aapko chahiye tha.
Chaliye, main unhi notes ko ab aur zyada "Hinglish" banane ki koshish karta hoon, taaki aapko
padhne aur samajhne mein aasani ho, especially competitive exams ke liye. Har point ko cover
karte hue:
Core Subtopics (Ab aur Hinglish mein):
1. Nervous System (Nervous System ya Tantrika Tantra): Structure and Function
●​ Nervous System Kya Hai? Yeh hamare shareer ka "control room" hai, jo brain (dimaag),
spinal cord (reedh ki haddi ki nerve), aur bahut saari nerves (nason) se bana hai. Iska
main kaam hai information ko idhar se udhar bhejna aur sab activities ko milakar chalana.
●​ Parts of Nervous System:
○​ Central Nervous System (CNS) (Kendriya Tantrika Tantra): Isme do main
cheezein aati hain:
■​ Brain (Dimaag/Mastishk): Humara sochne-samajhne ka center. Yahin se
hum decisions lete hain aur emotions feel karte hain. Iske alag-alag hisse
hain:
■​ Cerebrum (Bada Dimaag/Pramastishk): Sabse bada part. Thinking,
memory, learning, hamare senses (dekhna, sunna etc.) aur jo kaam
hum apni marzi se karte hain (voluntary movements), yeh sab control
karta hai. Iske do tukde hote hain - left aur right.
■​ Cerebellum (Chhota Dimaag/Anumastishk): Body ka balance,
coordination (taal-mel) aur posture (baithne-uthne ka dhang) maintain
karta hai. Smooth movements mein help karta hai.
■​ Brainstem (Dimaag ka Tana/Mastishk Stambh): Brain ko spinal cord
se jodta hai. Zindagi ke basic functions jaise saans lena (breathing),
heart rate, sona-jaagna, yeh sab control karta hai. Iske parts hain -
midbrain, pons, medulla oblongata.
■​ Spinal Cord (Meru Rajju): Brain se nikalti hai aur reedh ki haddi (vertebral
column) ke andar safe rehti hai. Yeh brain aur baaki shareer ke beech
"messages ka highway" hai. Reflex actions (jo turant hote hain, jaise garam
cheez se haath hatana) bhi control karti hai.
○​ Peripheral Nervous System (PNS) (Paridhiya Tantrika Tantra): CNS ke bahar
jitni bhi nerves hain, woh PNS mein aati hain. Iska kaam hai CNS ko shareer ke
baaki hisson se jodna.
■​ Somatic Nervous System (Humari Marzi Wala System): Jo kaam hum
apni marzi se karte hain (jaise chalna, likhna) aur sensory information (jaise
touch, pain) ko CNS tak pahunchata hai.
■​ Autonomic Nervous System (Apne Aap Chalne Wala System): Jo kaam
humare control mein nahi hote (involuntary functions) jaise heart rate,
digestion, saans ki speed, ankhon ki putli ka size, yeh sab control karta hai.
■​ Sympathetic Nervous System: "Ladai ya Bhaag jao" (Fight or flight)
response ke liye. Emergency mein activate hota hai - heart rate
badhata hai, energy deta hai.
■​ Parasympathetic Nervous System: "Aaram karo aur Digest karo"
(Rest and digest) response ke liye. Shaant time mein kaam karta hai -
heart rate kam karta hai, digestion mein help karta hai.
●​ Neurons (Nerve Cells/Tantrika Koshikayein): Nervous system ki sabse choti aur
important unit. Inhi se information aage badhti hai.
 ○​ Neuron ka Structure:
■​ Cell Body (Soma/Cyton): Neuron ka main hissa, isme nucleus hota hai. Cell
ke saare kaam yahi control karta hai.
■​ Dendrites (Signal Pakadne Wale Antennas): Cell body se nikle chote-chote
branches. Yeh doosre neurons se signals "receive" karte hain.
■​ Axon (Signal Bhejne Wala Taar): Cell body se nikla lamba, patla wire. Yeh
signals ko cell body se door, doosre neurons, muscles, ya glands tak le jaata
hai.
■​ Myelin Sheath (Axon ka Cover): Kuch axons ke upar ek moti, fatty layer
hoti hai. Yeh "insulation" ka kaam karti hai aur signal ko tezi se bhagati hai.
PNS mein Schwann cells aur CNS mein Oligodendrocytes ise banate hain.
Jahan yeh cover nahi hota, use Nodes of Ranvier kehte hain, yahan signal
"kood-kood kar" (saltatory conduction) jaata hai.
■​ Axon Terminals (Taar ke Sire): Axon ke end par chote branches, jinke
aakhir mein synaptic knobs (button jaise) hote hain. Yahan se
neurotransmitters (chemical messengers) nikalte hain.
○​ Types of Neurons:
■​ Sensory Neurons (Signal CNS Tak Lane Wale): Sense organs (jaise skin,
aankh, kaan) se CNS tak signals laate hain.
■​ Motor Neurons (Signal CNS Se Le Jane Wale): CNS se muscles ya glands
tak signals le jaate hain, jisse hum hilte-dulte hain ya glands se kuch nikalta
hai.
■​ Interneurons (Beech Wale Connection): CNS ke andar hote hain. Sensory
aur motor neurons ke beech "connection" banate hain. Sochne, sikhne jaise
complex kaamon mein important.
●​ Synaptic Transmission (Ek Neuron Se Doosre Tak Signal Kaise Jata Hai):
○​ Synapse (Connection Point): Ek neuron ka axon terminal aur doosre neuron ka
dendrite (ya cell body) jahan milte hain (par judte nahi, halka sa gap hota hai). Is
gap ko synaptic cleft kehte hain.
○​ Process (Kaise Hota Hai):
1.​ Jab ek electrical signal (action potential) axon terminal tak pahunchta hai, toh
wahan choti-choti thailiyan (synaptic vesicles) neurotransmitters ko synaptic
cleft (gap) mein chhod deti hain.
2.​ Neurotransmitters (Chemical Messengers): Yeh chemicals hote hain jo
message le jaate hain (e.g., acetylcholine, dopamine, serotonin).
3.​ Yeh neurotransmitters gap ko paar karke doosre neuron ke dendrites par lage
"locks" (receptors) mein "key" ki tarah fit ho jaate hain.
4.​ Isse doosre neuron mein ya toh current daud jaata hai (excitation - signal
ON) ya current ruk jaata hai (inhibition - signal OFF), yeh depend karta hai
kaunsa neurotransmitter aur receptor hai.
5.​ Baad mein neurotransmitters ya toh toot jaate hain, ya wapas pehle wale
neuron mein chale jaate hain (reuptake).
●​ Neuroanatomy (Dimaag ki Banawat ki Padhai): Brain aur nervous system ke structure
ki study. Isme brain ke alag-alag lobes (frontal, parietal, temporal, occipital) aur unke
kaam, aur important hisse jaise hippocampus (memory ke liye), amygdala (emotions ke
liye), thalamus (sensory information ka station), hypothalamus (hormones aur basic
zarooraton ka control) aate hain.
2. Visual System (Dekhne Ka System/Drishti Pranali): Anatomy and Physiology
●​ Anatomy of the Eye (Aankh ki Banawat):
○​ Outer Layer (Bahri Parat):
■​ Sclera (Aankh ka Safed Hissa): Aankh ka bahar wala, mazboot, safed part.
Bachav karta hai.
■​ Cornea (Aankh ka Sheesha): Sclera ka aage ka transparent (pardarshi)
hissa. Light ko modkar (refract) aankh mein entry deta hai. Sabse zyada light
yahin mudti hai.
○​ Middle Layer (Beech ki Parat - Uvea):
■​ Choroid (Khoon ki Nason Wali Parat): Sclera ke neeche. Blood vessels se
bhari hoti hai. Retina ko khana (nourishment) deti hai aur andar light ko
reflect hone se rokti hai.
■​ Ciliary Body (Lens Ko Control Karne Wala Hissa): Cornea aur iris ke
jodne ki jagah par. Isme ciliary muscles hote hain jo lens ka shape badal kar
"focus" karne mein help karte hain (accommodation). Aqueous humor (ek
liquid) bhi banata hai.
■​ Iris (Aankh ka Rang Wala Part): Aankh ka colored hissa. Iske beech mein
ek chhed (opening) hota hai jise pupil (putli) kehte hain. Iris muscles putli ka
size control karke aankh mein jaane wali light ki quantity ko regulate karte
hain.
○​ Inner Layer (Andaruni Parat):
■​ Retina (Jahan Image Banti Hai): Aankh ki sabse andar wali light-sensitive
layer. Isme photoreceptor cells (light ko pakadne wale cells) hote hain:
■​ Rods (Kam Roshni Mein Dekhne Wale Cells): Dheemi light (kam
roshni) mein dekhne ke liye (scotopic vision). Black and white dikhate
hain. Inme Rhodopsin pigment hota hai. Retina ke kinaron (periphery)
mein zyada hote hain.
■​ Cones (Tez Roshni Aur Rang Dekhne Wale Cells): Bright light (tez
roshni) mein dekhne aur color vision (rang dekhne) ke liye (photopic
vision). Choti-choti details bhi inhi se dikhti hain. Inme Iodopsin pigment
hota hai. Fovea (retina ka center) mein bahut zyada hote hain. Teen
type ke cones hote hain jo red, green, aur blue light ke liye sensitive
hote hain.
■​ Fovea (Sabse Saaf Dekhne ki Jagah): Retina ka woh chota sa area jahan
sabse clear (sharp vision) dikhta hai. Yahan sirf cones hote hain.
■​ Optic Disc (Blind Spot/Andh Bindu): Woh jagah jahan se optic nerve
aankh se bahar nikalti hai. Yahan koi rods ya cones nahi hote, isliye yahan
image nahi banti.
○​ Lens (Aankh ka Lens): Putli ke peeche, transparent, dono taraf se ubhra hua
(biconvex) structure. Ciliary muscles ki help se apna shape badal kar light ko retina
par focus karta hai (accommodation).
○​ Aqueous Humor (Aankh ka Paani): Cornea aur lens ke beech mein saaf, paani
jaisa liquid. Cornea aur lens ko khana deta hai aur aankh ke andar ka pressure
(intraocular pressure) maintain karta hai.
○​ Vitreous Humor (Aankh ki Jelly): Lens ke peeche aur retina ke saamne, jelly jaisa
substance. Aankh ke shape ko maintain karta hai aur retina ko support deta hai.
●​ Neural Pathways of Vision (Dekhne ki Information Dimaag Tak Kaise Jati Hai):
1.​ Light aankh mein ghusti hai, cornea, pupil, aur lens se hoti hui retina par focus hoti
hai.
 2.​ Retina mein rods aur cones light energy ko electrical signals (current) mein badal
dete hain.
3.​ Yeh signals bipolar cells aur phir ganglion cells tak jaate hain. Ganglion cells ke
"taar" (axons) milkar optic nerve (dekhne wali nas) banate hain.
4.​ Dono aankhon ki optic nerves dimaag ki taraf jaati hain aur Optic Chiasm par cross
karti hain. Yahan par, har aankh ke naak ki taraf wale visual field se aane wale
"taar" cross karte hain, jabki kaan ki taraf wale "taar" seedhe rehte hain.
5.​ Optic chiasm ke baad yeh "taar" optic tracts banate hain.
6.​ Zyadatar optic tract ke "taar" Lateral Geniculate Nucleus (LGN) (thalamus ka hissa)
mein synapse karte hain (connection banate hain).
7.​ LGN se neurons optic radiations ke through Primary Visual Cortex (dekhne ka main
center, occipital lobe mein) tak signals le jaate hain.
8.​ Visual cortex mein information "process" hoti hai, jisse hum image ko samajh paate
hain. Phir yeh information dimaag ke doosre hisson mein jaati hai aur detail mein
process hone ke liye (jaise cheez kya hai - 'what' pathway, aur kahan hai - 'where'
pathway).
●​ Visual Perception Mechanisms (Hum Cheezon Ko Dekh Kar Kaise Samajhte Hain):
○​ Light and Dark Adaptation: Aankhon ka kam ya zyada roshni ke hisaab se adjust
hona.
○​ Color Vision (Rang Kaise Dikhte Hain): Cones ke teen types (red, green, blue)
alag-alag light ki "wavelengths" par react karte hain. Theories:
■​ Trichromatic Theory (Young-Helmholtz): Teen type ke cones hote hain (R,
G, B). Baaki sab rang inke mix hone se dikhte hain. Color blindness isse
samjhi jaati hai.
■​ Opponent-Process Theory (Hering): Rang "jodi" (pairs) mein kaam karte
hain: red-green, blue-yellow, black-white. Ek rang ko dekhne se doosra dab
jaata hai. Afterimages (kisi rang ko dekhne ke baad uska ulta rang dikhna)
isse samjhi jaati hai. Dono theories apni-apni jagah sahi hain.
○​ Depth Perception (Gehrai Ka Ehsaas): Duniya ko 3D mein dekhne ki ability. Iske
liye monocular cues (ek aankh se milne wale signals - jaise kaunsi cheez aage hai,
kaunsi peeche) aur binocular cues (dono aankhon se milne wale signals - jaise
dono aankhon mein thodi alag image banna) use hote hain.
○​ Form Perception (Cheezon Ka Shape Samajhna): Objects ko unke shape se
pehchanana. Gestalt principles (jaise cheezein group mein dikhna) help karte hain.
○​ Motion Perception (Hilti Hui Cheezon Ko Samajhna): Moving objects ko detect
karna.
○​ Visual Constancies (Cheezon Ka Asli Size/Shape Samajhna): Cheezon ko size,
shape, brightness, aur color mein "constant" (ek jaisa) samajhna, bhale hi unki
retina par image badal rahi ho (jaise door se aadmi chota dikhta hai, par hume pata
hai uska size wahi hai).
3. Hearing (Auditory System) (Sunne Ka System/Shravan Pranali): Structure and Function
●​ Structure of the Ear (Kaan ki Banawat):
○​ Outer Ear (Bahari Kaan):
■​ Pinna (Kaan ka Bahari Hissa): Kaan ka dikhne wala, cartilage ka bana part.
Sound waves ko ikattha karke ear canal ki taraf bhejta hai.
■​ Auditory Canal (Kaan ki Nali): Pinna se eardrum tak ki tube. Sound waves
ko thoda tez (amplify) karke eardrum tak le jaati hai. Isme glands hote hain jo
earwax (kaan ka mail) banate hain (safai aur bachav ke liye).
 ○​ Middle Ear (Beech ka Kaan): Hawa se bhari jagah.
■​ Tympanic Membrane (Eardrum/Kaan ka Parda): Outer aur middle ear ke
beech patli si "jhilli" (membrane). Sound waves se vibrate (hilta) hai.
■​ Ossicles (Kaan ki Choti Haddiyan): Eardrum ke vibration ko inner ear tak le
jaane wali teen choti haddiyan (shareer ki sabse choti haddiyan):
■​ Malleus (Hathodi): Eardrum se judi hoti hai.
■​ Incus (Nihai): Malleus aur stapes ke beech mein.
■​ Stapes (Rakaab): Incus se judi hoti hai aur oval window (inner ear ka
gate) par fit hoti hai. Yeh haddiyan vibration ko aur tez karti hain.
■​ Eustachian Tube (Middle Ear se Gale Tak ki Nali): Middle ear ko naak ke
peeche gale (nasopharynx) se jodti hai. Middle ear mein hawa ka pressure
barabar rakhti hai (jaise jab hum upar jaate hain ya kuch nigalte hain).
○​ Inner Ear (Andaruni Kaan): Liquid se bhari jagah.
■​ Cochlea (Snail Jaisa Part): Snail (ghonghe) ke shape ka, ghumaavdaar
structure. Sunne ka main organ. Iske andar teen liquid se bhari chambers
hote hain. Scala Media (beech wala chamber) mein Organ of Corti hota hai.
■​ Organ of Corti (Sunne Wale Cells Ka Group): Cochlea ke andar, basilar
membrane par hota hai. Isme hair cells (baal jaise cells) hote hain. Yeh sound
vibrations ko electrical signals (current) mein badalte hain. Hair cells ke upar
tectorial membrane hoti hai.
■​ Vestibular System (Balance Banane Wala System): Balance ke liye
responsible. Iske parts hain: Semicircular Canals (sar ke ghumne ko detect
karte hain) aur Otolith Organs (seedhi line mein hilne aur sar ki position ko
detect karte hain).
●​ Auditory Pathways (Sunne ki Information Dimaag Tak Kaise Jati Hai):
1.​ Sound waves pinna ikattha karta hai aur auditory canal se eardrum tak jaati hain.
2.​ Eardrum vibrate karta hai, jisse ossicles (malleus, incus, stapes) vibrate karte hain.
3.​ Stapes oval window par pressure daalta hai, jisse cochlea ke andar liquid mein
pressure waves (lehrein) banti hain.
4.​ Yeh pressure waves basilar membrane ko vibrate karti hain. Basilar membrane ke
alag-alag hisse alag-alag frequency ki sound par zyada vibrate karte hain (high
frequency base par, low frequency upar ki taraf - tonotopic organization).
5.​ Basilar membrane ke hilne se Organ of Corti ke hair cells mudte (bend) hain.
6.​ Hair cells ke mudne se unme current banta hai.
7.​ Yeh signals auditory nerve (sunne wali nas) dimaag tak le jaati hai.
8.​ Signals brainstem mein cochlear nuclei, phir superior olivary nucleus (aawaz kahan
se aa rahi hai, yeh pata lagane mein help), inferior colliculus (midbrain), Medial
Geniculate Nucleus (MGN) (thalamus ka hissa) se hote hue Primary Auditory
Cortex (sunne ka main center, temporal lobe mein) tak pahunchte hain.
9.​ Auditory cortex mein sound ki "processing" hoti hai (jaise aawaz kitni tez hai, patli
hai ya moti).
●​ Processing of Sound (Aawaz Ko Kaise Samajhte Hain):
○​ Pitch (Aawaz ka Patlapan ya Motapan): Sound ki frequency se related.
■​ Place Theory: Basilar membrane ka kaunsa hissa vibrate kar raha hai, usse
pitch ka pata chalta hai (high frequency ke liye base, low ke liye upar wala
hissa).
■​ Frequency Theory: Basilar membrane kitni tezi se vibrate kar rahi hai, usse
pitch ka pata chalta hai (low frequency ke liye).
 ■​ Volley Principle: Medium frequencies ke liye, neurons group mein fire karte
hain.
○​ Loudness (Aawaz Kitni Tez Hai): Sound ki intensity (amplitude) se related. Zyada
tez aawaz se hair cells zyada stimulate hote hain.
○​ Timbre (Aawaz ki Quality): Jisse hum do alag musical instruments ki same pitch
aur loudness wali aawaz ko pehchan paate hain.
○​ Sound Localization (Aawaz Kahan Se Aa Rahi Hai): Binaural cues (dono kaano
se milne wale signals) use hote hain:
■​ Interaural Time Difference (ITD): Aawaz ko ek kaan tak pahunchne mein
doosre kaan se thoda alag time lagta hai.
■​ Interaural Intensity Difference (IID): Ek kaan mein aawaz doosre se thodi
kam ya zyada tez sunai deti hai (high frequency sounds ke liye).
4. Somatosenses (Shareer ki Touch, Pain Wali Samvednayein): Touch, Pain, Temperature,
Proprioception
●​ Somatosenses Kya Hain? Yeh woh senses hain jo shareer ki skin aur andar se
information dete hain.
○​ Touch (Chhoona/Sparsh): Pressure, vibration, cheez kaisi hai (texture). Skin mein
alag-alag "detectors" (receptors) hote hain: Meissner's, Pacinian, Merkel's, Ruffini.
○​ Pain (Dard/Peeda): Jab shareer ko chot lagti hai ya lagne wali hoti hai toh feel hota
hai. Protective hai.
■​ Nociceptors (Dard Ke Detectors): Pain receptors. Free nerve endings (khuli
hui nason ke sire).
■​ Types of Pain Fibers: A-delta fibers (tez, chubhne wala dard) aur C fibers
(halka, faila hua dard).
■​ Gate Control Theory of Pain: Spinal cord mein ek "gate" hota hai jo dard ke
signals ko dimaag tak jaane se rok ya allow kar sakta hai. Malish karne se ya
dhyan kahin aur lagane se yeh "gate" band ho sakta hai.
○​ Temperature (Thanda-Garam/Taapman): Garmi aur thandi ko detect karna.
Thermoreceptors hote hain.
○​ Proprioception (Apne Shareer Ki Position Ka Ehsaas): Bina dekhe apne
haath-pair kahan hain, yeh pata hona. Receptors muscles (muscle spindles),
tendons (Golgi tendon organs), aur joints mein hote hain.
●​ Pathways for Somatosensory Information (Yeh Information Dimaag Tak Kaise Jati
Hai):
1.​ Receptors se information sensory neurons ke through spinal cord mein jaati hai.
2.​ Dorsal Column-Medial Lemniscus Pathway: Fine touch (halka sparsh), vibration,
proprioception ki information le jaata hai.
3.​ Anterolateral System (Spinothalamic Tract): Pain, temperature, rough touch ki
information le jaata hai.
4.​ Yeh pathways thalamus se hote hue primary somatosensory cortex (parietal lobe
mein, yahan shareer ka "map" hota hai) tak jaate hain.
5. Sleep and Sleep Disorders (Neend aur Neend ki Bimariyan)
●​ Stages of Sleep (Neend ke Stages): Neend do type ki hoti hai - NREM aur REM, jo
cycle mein chalti hai (ek cycle kareeb 90-110 min).
○​ NREM (Non-Rapid Eye Movement) Sleep:
■​ Stage 1 (N1): Halki neend. Jaagne aur sone ke beech ka time. Aankhein
dheere-dheere ghoomti hain. Theta waves.
■​ Stage 2 (N2): Thodi gehri neend. Heart rate, body temperature kam. Sleep
 spindles aur K-complexes (EEG waves).
■​ Stage 3 (N3) (Slow-Wave Sleep - SWS / Gehri Neend): Sabse gehri neend.
Uthana mushkil. Body repair aur growth ke liye important. Delta waves.
Sleepwalking (neend mein chalna), night terrors (neend mein darr jana) isi
stage mein hote hain.
○​ REM (Rapid Eye Movement) Sleep:
■​ Jaagne ke kareeb 70-90 min baad pehla REM aata hai.
■​ Aankhein tezi se ghoomti hain.
■​ Brain activity bahut zyada, jaise jaage hue हों (ise "paradoxical sleep" bhi
kehte hain).
■​ Saans irregular. Heart rate, blood pressure badh jaata hai.
■​ Body ke main muscles "paralyzed" ho jaate hain (REM atonia), taaki hum
sapne mein harkatein na karein.
■​ Asli jaise sapne (vivid dreams) isi stage mein aate hain. Memory ko pakka
karne (consolidation) ke liye important.
○​ Sleep Cycle: N1 → N2 → N3 → N2 → REM. Yeh cycle raat bhar 4-6 baar chalta
hai.
●​ Brain Mechanisms Regulating Sleep and Dreaming (Neend aur Sapno ko Control
Karne Wale Dimaag ke Parts):
○​ Circadian Rhythms (24 Ghante ki Body Clock): Internal clock jo sone-jaagne ka
cycle control karta hai.
■​ Suprachiasmatic Nucleus (SCN): Hypothalamus mein. Master clock.
Roshni se set hota hai.
■​ Melatonin: Pineal gland se nikalne wala hormone. Andhere mein badhta hai,
neend laata hai.
○​ Homeostatic Sleep Drive: Jitna lamba jaagte hain, utni neend aati hai. Adenosine
chemical badhta hai jaagne par.
○​ Brain Structures: Brainstem (Reticular Formation - jagaata hai), Hypothalamus
(SCN, VLPO - sulata hai, Orexin - jagaata hai), Thalamus, Basal Forebrain.
○​ Neurotransmitters: Wakefulness ke liye (Acetylcholine, Norepinephrine, Serotonin,
Dopamine, Histamine, Orexin). NREM sleep ke liye (GABA, Adenosine). REM
sleep ke liye (Acetylcholine).
○​ Dreaming Mechanisms: REM sleep mein limbic system (emotions) active.
Prefrontal cortex (logic) kam active.
■​ Activation-Synthesis Hypothesis: Dimaag ke random signals se sapne
bante hain.
●​ Common Sleep Disorders (Aam Neend ki Pareshaniyan):
○​ Insomnia (Neend Na Aana): Neend aane mein, ya sote rehne mein dikkat. Stress,
anxiety bade कारण.
○​ Sleep Apnea (Sote Waqt Saans Rukna): Neend mein breathing baar-baar ruk
jaati hai. Obstructive (gale ki muscles relax) aur Central (dimaag signal nahi deta).
Kharraate aana, din mein neend aana.
○​ Narcolepsy (Din Mein Achanak So Jana): Bahut zyada neend aana aur
achaanak so jaana. Cataplexy (emotions se muscle weakness), sleep paralysis.
Orexin ki kami se.
○​ Restless Legs Syndrome (RLS): Pairon mein ajeeb si feeling aur hilane ki ichha.
○​ Parasomnias (Neend Mein Ajeeb Harkatein): Sleepwalking, Night Terrors
(NREM-3 mein). REM Sleep Behavior Disorder (RBD) (sapno mein actions karna).
 Nightmare Disorder (darawne sapne).
6. Methods of Study (Brain Research ki Techniques)
●​ Ablation/Lesion Studies (Brain ka Part Nikalna ya Damage Karna):
○​ Logic: Agar brain ka koi part damage karne se koi function ruk jaaye, toh woh part
us function ke liye zaroori hai.
○​ Types: Electrolytic (current se), Excitotoxic (chemical se), Reversible (temporary).
○​ Limitations: Dusre parts bhi affect ho sakte hain. Mostly animals par.
●​ Electrical Brain Stimulation (Current Dekar Brain ko Active Karna):
○​ Logic: Stimulation se kaunsa behavior ya sensation hota hai, yeh dekhna.
○​ Techniques: Deep Brain Stimulation (DBS) (Parkinson's mein use hota hai),
Transcranial Magnetic Stimulation (TMS) (non-invasive).
●​ Chemical Brain Stimulation (Chemical Daal Kar Brain ko Active Karna):
○​ Logic: Chemical ka behavior par kya asar hota hai. Neurotransmitter systems ko
samajhne mein help.
●​ Imaging Methods (Brain ki Tasveerein Lena):
○​ EEG (Electroencephalography): Scalp par electrodes lagakar brain ki electrical
activity record karna. Sleep, epilepsy mein use. Good time resolution, poor space
resolution. ERPs (Event-Related Potentials) specific events ke response mein brain
waves.
○​ fMRI (Functional Magnetic Resonance Imaging): Brain mein blood flow (oxygen
level) ke changes ko dekhkar activity pata lagana. Good space resolution.
○​ CT Scan (Computed Tomography): X-rays se brain ke "slices" ki image. Structure
dekhne ke liye (tumor, stroke).
○​ MRI (Magnetic Resonance Imaging): Magnetic fields se detailed structural image.
CT se behtar.
○​ PET Scan (Positron Emission Tomography): Radioactive tracer (jaise glucose)
inject karke activity dekhna. Function aur chemical processes.
7. Endocrine System (Hormone Banane Wala System)
●​ Endocrine System Kya Hai? Glands ka network jo hormones banate aur release karte
hain. Hormones chemical messengers hain jo blood mein ghoom kar target cells par
kaam karte hain. Nervous system se dheere par asar lamba.
●​ Hormones: Chemical substances, endocrine glands se nikalte, blood mein jaate, target
cells tak pahunchte.
●​ Major Endocrine Glands and Hormones:
○​ Hypothalamus: Brain ka part. Pituitary ko control karta hai. ADH, Oxytocin banata
hai (posterior pituitary se release hote hain). Basic drives, temperature, emotions
control.
○​ Pituitary Gland ("Master Gland"):
■​ Anterior Pituitary: Growth Hormone (GH), Prolactin (milk), ACTH (adrenal
cortex ko stimulate), TSH (thyroid ko stimulate), FSH & LH (sex hormones,
reproduction).
■​ Posterior Pituitary: ADH (paani ka balance), Oxytocin (childbirth, bonding).
○​ Pineal Gland: Melatonin (neend ka cycle).
○​ Thyroid Gland: Thyroxine (T4), T3 (metabolism, growth). Calcitonin (calcium kam
karta hai).
○​ Parathyroid Glands: Parathyroid Hormone (PTH) (calcium badhata hai).
○​ Adrenal Glands:
■​ Adrenal Cortex (bahar wala): Cortisol (stress hormone, blood sugar
 badhata hai), Aldosterone (salt/water balance), Androgens (sex hormones).
■​ Adrenal Medulla (andar wala): Epinephrine (Adrenaline), Norepinephrine
(Noradrenaline) - "fight or flight" response.
○​ Pancreas: Insulin (glucose kam karta hai), Glucagon (glucose badhata hai).
Diabetes.
○​ Gonads (Sex Glands):
■​ Ovaries (Females): Estrogens, Progesterone (female characteristics,
pregnancy).
■​ Testes (Males): Testosterone (male characteristics, libido).
●​ Regulation: Negative feedback (hormone zyada toh production kam), Positive feedback
(hormone zyada toh production aur zyada), Neural control (hypothalamus).
8. Motivation and Emotion (Kuch Karne ki Chah aur Feelings)
●​ Motivation (Abhiprerna): Jo cheez hume koi kaam shuru karne, karte rehne, aur poora
karne ke liye "push" karti hai.
○​ Basic Drives (Zaroori Needs):
■​ Hunger (Bhookh):
■​ Peripheral (Shareer ke Signals): Ghrelin (pet khali hone par), pet ka
bharna.
■​ Central (Dimaag ke Signals - Hypothalamus): Lateral Hypothalamus
(LH - bhookh lagata hai), Ventromedial Hypothalamus (VMH - bhookh
mitata hai). Leptin (fat cells se, bhookh kam karta hai).
■​ Thirst (Pyaas): Osmotic (namkeen khane se), Hypovolemic (blood/fluid loss
se). ADH release hota hai.
■​ Sex (Kaam Pravritti): Hormones (Testosterone, Estrogen). Brain parts
(Hypothalamus, Amygdala). Dopamine (reward).
●​ Emotion (Samveg/Bhavnayein): Ek complex state jisme feeling, shareer mein badlav
(arousal), aur behavior hota hai.
○​ Physiological Correlates (Shareer Mein Kya Hota Hai Emotions Ke Time):
■​ ANS Activity: Sympathetic (fight or flight - heart rate tez), Parasympathetic
(calm).
■​ Endocrine System: Adrenaline, Cortisol.
■​ Brain Structures: Limbic System (Amygdala - dar, gussa; Hippocampus -
emotional memories; Hypothalamus - ANS/hormone control), Prefrontal
Cortex (PFC - emotion control, decision making), Insula (disgust, body
awareness).
○​ Major Theories of Emotion (Feelings Kaise Aati Hain - Alag Alag Vichar):
■​ James-Lange Theory: Event → Body mein reaction (heart tez) → Usko
interpret karke emotion (dar). "Hum rote hain isliye dukhi hote hain."
■​ Cannon-Bard Theory: Event → Body mein reaction AUR emotion, dono ek
saath, alag-alag dimaag mein process hote hain.
■​ Schachter-Singer Two-Factor Theory: Event → Body mein reaction →
Sochna ki reaction kyun hua (cognitive label) → Emotion. (Epinephrine
injection experiment).
■​ Papez-MacLean Theory (Limbic System): Emotions limbic system (Papez
circuit, amygdala etc.) ke kaam se aate hain.
9. Learning and Memory (Seekhna aur Yaad Rakhna): Electrophysiological Mechanisms
●​ Synaptic Plasticity (Connections ka Badalna): Synapses (neuron ke connections) ka
experience ke saath strong ya weak hona. Learning ka main base.
 ○​ Hebbian Learning: "Jo neurons ek saath fire karte hain, woh ek saath jud jaate
hain."
●​ Long-Term Potentiation (LTP) (Connection ka Strong Hona): Jab do neurons ek saath
baar-baar activate hote hain, toh unke beech ka signal transmission strong aur
long-lasting ho jaata hai. Hippocampus mein study kiya gaya.
○​ Kaise Hota Hai (NMDA aur AMPA receptors - glutamate ke liye): High frequency
stimulation se glutamate nikalta hai. AMPA receptor se Na+ andar, cell depolarize
hota hai. Phir NMDA receptor se Mg2+ block hatta hai aur Ca2+ andar jaata hai.
Ca2+ LTP ko trigger karta hai.
○​ Result: AMPA receptors zyada sensitive, zyada AMPA receptors, ya naye synapse
banna.
●​ Long-Term Depression (LTD) (Connection ka Weak Hona): Low frequency stimulation
se synaptic strength kam hoti hai. Purani yaadein mitane mein help.
●​ Brain Structures: Hippocampus (new memories), Amygdala (emotional learning),
Cerebellum (motor skills), Cortex (long-term storage).
10. Arousal and Attention (Hosh aur Dhyan)
●​ Arousal (Hosh/Jagrit Avastha): Jaagne aur alert rehne ki state. Deep sleep se high
excitement tak.
○​ Neural Basis:
■​ Reticular Activating System (RAS): Brainstem mein network, cortex ko
jagaaye rakhta hai.
■​ Neurotransmitters: Acetylcholine, Norepinephrine, Serotonin, Dopamine,
Histamine, Orexin - yeh sab jagaane mein help karte hain.
○​ Yerkes-Dodson Law: Performance aur arousal ka U-shape relation. Moderate
arousal best.
●​ Attention (Dhyan/Avdhaan): Kisi ek cheez par concentrate karna, baaki ko ignore karna.
○​ Mechanisms:
■​ Selective Attention: Ek cheez select karna (Cocktail party effect).
■​ Divided Attention: Ek saath kayi cheezon par dhyan (multitasking).
■​ Sustained Attention: Lambe time tak dhyan lagana.
○​ Brain Structures: Posterior Parietal Cortex (PPC) (kahan dhyan dena hai),
Prefrontal Cortex (PFC) (dhyan ko control karna), Thalamus (filter), Superior
Colliculus (aankhon ka movement).
Additional Subtopics (Kuch Universities Mein Extra):
11. Brain Imaging Techniques (Dimaag ki Tasveerein Lene ki Techniques): (Pehle bhi
discuss kiya hai)
●​ Structural Imaging (Banawat Dekhne Ke Liye):
○​ CT Scan: X-rays se "slices". Tumor, stroke.
○​ MRI: Magnetic fields se high-resolution image.
○​ DTI (Diffusion Tensor Imaging): MRI se white matter (connections) ke रास्ते
dekhna.
●​ Functional Imaging (Kaam Dekhne Ke Liye):
○​ EEG: Electrical activity.
○​ MEG: Magnetic fields.
○​ PET Scan: Radioactive tracer se activity.
○​ fMRI: Blood oxygen level se activity.
○​ NIRS (Near-Infrared Spectroscopy): Light se cortical activity.
12. Psychophysiological Disorders (Mann Ke Karan Shareer Ki Bimariyan)
 ●​ Kya Hain? Physical bimariyan jo psychological factors (stress, emotions) se shuru ya
badh jaati hain.
●​ Link Kaise Hai: Stress se ANS (sympathetic), HPA axis (cortisol), immune system affect
hote hain. Unhealthy behavior bhi.
●​ Examples:
○​ Insomnia (Neend na aana).
○​ Headaches: Tension headaches (stress se muscle tight), Migraines (stress trigger).
○​ Cardiovascular Diseases: Hypertension (high BP), Coronary Heart Disease.
Stress se badhte hain.
○​ GI Disorders: Irritable Bowel Syndrome (IBS), Peptic Ulcers (stress se bigad sakte
hain).
○​ Asthma, Skin Disorders (Eczema), Rheumatoid Arthritis: Stress se symptoms
badh sakte hain.
●​ Management: Medical treatment + psychological help (stress management, CBT) +
lifestyle changes.
13. Developmental Aspects (Bachpan Se Badhne Tak Behavior Aur Brain Ka Vikas)
●​ Biological Foundations of Behavior (Behavior Ke Peeche Biology): Genes,
hormones, brain development kaise behavior par asar daalte hain.
○​ Genetics and Behavior: Genes se brain aur behavior ka blueprint milta hai. Twin
studies, adoption studies se pata chalta hai. Gene-Environment interaction.
○​ Hormonal Influences: Organizational effects (bachpan mein permanent change),
Activational effects (baad mein temporary change).
●​ Developmental Neurobiology (Brain Kaise Develop Hota Hai):
○​ Stages:
1.​ Neurogenesis (Naye neurons banna): Mostly Maa ke pet mein.
2.​ Cell Migration (Neurons ka apni jagah jaana).
3.​ Differentiation (Neurons ka special type banna).
4.​ Axon Growth and Guidance (Axons ka target tak pahunchna).
5.​ Synaptogenesis (Connections banna). Bahut tezi se bachpan mein.
6.​ Neuronal Cell Death (Apoptosis) (Faltu neurons ka marna).
7.​ Synaptic Pruning (Faltu connections ka hatna). Adolescence tak chalta
hai.
8.​ Myelination (Axons par cover chadhna). Speed badhata hai.
Adolescence/early adulthood tak.
○​ Critical/Sensitive Periods: Jab brain kisi ‫ خاص‬experience ke liye bahut sensitive
hota hai (jaise language sikhna).
○​ Plasticity: Brain ka experience ke saath badalna. Bachpan mein sabse zyada.
○​ Teratogens: Environment ki cheezein jo bachche ko nuksan pahuncha sakti hain
(alcohol, drugs).
○​ Brain Development Milestones: Prefrontal cortex sabse late (early 20s tak)
mature hota hai, isliye teenagers zyada risk lete hain.
Umeed hai ab yeh notes aapko zyada "Hinglish" lage honge aur exam ki taiyari mein help
karenge! Koi aur topic ho toh batana!
Bilkul! Neurotransmitters aur hormones alag-alag disorders mein important role play karte hain.
Main aapko iske baare mein detail mein batata hoon, Hinglish mein:
Pehle, Types of Neurotransmitters (न्यरू ोट्रांसमीटर के प्रकार) aur unke General Kaam:
Neurotransmitters chemical messengers hote hain jo nerve cells (neurons) ke beech signal
bhejte hain.
1.​ Acetylcholine (ACh) (एसिटाइलकोलाइन):
○​ Kaam: Muscle contraction ( मांसपेशियों का सिकुड़ना), memory (याददाश्त), learning
(सीखना), aur attention (ध्यान).
○​ PNS (Peripheral Nervous System) mein, yeh muscles ko activate karta hai. CNS
(Central Nervous System) mein, yeh jagrit rehne (arousal) aur cognitive functions
mein role play karta hai.
2.​ Dopamine (DA) (डोपामाइन):
○​ Kaam: "Reward" aur pleasure ( इनाम और खश ु ी), motivation (प्रेरणा), motor control
(शारीरिक गति का नियंत्रण), focus (ध्यान केंद्रित करना), aur executive functions (निर्णय
लेना, योजना बनाना).
○​ Isko "feel-good" neurotransmitter bhi kehte hain.
3.​ Serotonin (5-HT) (सेरोटोनिन):
○​ Kaam: Mood regulation (मनोदशा का नियंत्रण), sleep (नींद), appetite (भख ू ), digestion
(पाचन), learning (सीखना), memory (याददाश्त), aur anxiety (चिंता) ko control karna.
○​ Mood aur emotional well-being ke liye bahut important hai.
4.​ Norepinephrine (NE) / Noradrenaline (NA) (नॉरपेनेफ्रीन / नॉरएड्रेनालाईन):
○​ Kaam: "Fight or flight" response (तनाव प्रतिक्रिया), alertness (सतर्क ता), arousal
(उत्तेजना), attention (ध्यान), stress response (तनाव प्रतिक्रिया), heart rate aur blood
pressure ko badhana.
○​ Yeh hormone ki tarah adrenal gland se bhi release hota hai.
5.​ Epinephrine / Adrenaline (एपिनेफ्रीन / एड्रेनालाईन):
○​ Kaam: Primarily ek hormone hai (adrenal gland se), lekin brain mein
neurotransmitter ki tarah bhi thoda kaam karta hai. Strong emotions jaise fear ya
anger ke time "fight or flight" response mein crucial. Heart rate, blood flow,
breathing ko tez karta hai.
6.​ GABA (Gamma-Aminobutyric Acid) (गाबा):
○​ Kaam: CNS ka main inhibitory neurotransmitter (दिमाग की गतिविधि को शांत करने
वाला). Anxiety (चिंता) kam karta hai, calming effect (शांतिदायक प्रभाव) deta hai, sleep
(नींद) mein help karta hai, aur seizures (दौरे ) ko rokta hai.
○​ Brain ki overactivity ko kam karta hai.
7.​ Glutamate (ग्लट ू ामेट):
○​ Kaam: CNS ka main excitatory neurotransmitter (दिमाग की गतिविधि को बढ़ाने वाला).
Learning (सीखना) aur memory (याददाश्त) (especially Long-Term Potentiation - LTP)
mein bahut important hai.
○​ Brain mein sabse zyada paya jaane wala neurotransmitter.
8.​ Endorphins (एंडोर्फि न):
○​ Kaam: Natural pain reliever (प्राकृतिक दर्द निवारक) aur pleasure enhancers (खश ु ी बढ़ाने
वाले). Stress aur pain ke response mein release hote hain. "Runner's high" mein
inka role hota hai.
○​ Opioids (jaise morphine) inhi ke receptors par kaam karte hain.
9.​ Histamine (हिस्टामाइन):
○​ Kaam: Wakefulness (जागत ृ रहना), arousal (उत्तेजना), appetite control (भख ू नियंत्रण),
aur immune response (एलर्जी में ). Antihistamine dawaiyan neend laati hain kyunki
 woh iske effect ko block karti hain.
10.​Oxytocin (ऑक्सीटोसिन): (Hormone bhi hai)
○​ Kaam: Social bonding ("love hormone" / "cuddle hormone"), trust (विश्वास),
empathy (समानभ ु ति
ू ), childbirth (प्रसव), aur milk ejection (स्तनपान).
11.​Vasopressin (ADH) (वैसोप्रेसिन): (Hormone bhi hai)
○​ Kaam: Social behavior, aggression (आक्रामकता), pair bonding (जोड़ी बनाना), water
balance (पानी का संतल ु न), aur blood pressure regulation (रक्तचाप नियंत्रण).
Ab, Hormones (हार्मोन) aur unke General Kaam (jo behavior aur mood se related hain):
Hormones bhi chemical messengers hain, lekin yeh endocrine glands se nikalte hain aur blood
ke through travel karte hain. Inka asar neurotransmitters se dheema par zyada der tak rehta hai.
1.​ Cortisol (कोर्टिसोल):
○​ Gland: Adrenal cortex (एड्रीनल कॉर्टेक्स).
○​ Kaam: "Stress hormone." Stress ke time release hota hai. Blood sugar aur
metabolism ko regulate karta hai, inflammation kam karta hai, immune system ko
suppress kar sakta hai. Wakefulness mein bhi role hai.
2.​ Melatonin (मेलाटोनिन):
○​ Gland: Pineal gland (पीनियल ग्रंथि).
○​ Kaam: Sleep-wake cycle (नींद-जागने का चक्र) ko regulate karta hai. Andhere mein
iska level badhta hai, jisse neend aati hai.
3.​ Thyroid Hormones (T3 - Triiodothyronine, T4 - Thyroxine) (थायरॉइड हार्मोन):
○​ Gland: Thyroid gland (थायरॉइड ग्रंथि).
○​ Kaam: Metabolism (चयापचय), energy levels (ऊर्जा स्तर), growth (विकास), mood
(मनोदशा), aur brain development (मस्तिष्क विकास).
4.​ Estrogen (एस्ट्रोजन):
○​ Gland: Ovaries (अंडाशय), adrenal glands.
○​ Kaam: Female sexual development (महिला यौन विकास) aur reproductive functions
(प्रजनन कार्य). Mood, cognitive functions (संज्ञानात्मक कार्य), aur bone health par bhi
asar daalta hai.
5.​ Progesterone (प्रोजेस्टे रोन):
○​ Gland: Ovaries (अंडाशय), adrenal glands.
○​ Kaam: Menstrual cycle (मासिक धर्म चक्र) aur pregnancy (गर्भावस्था) ko regulate karta
hai. Calming effect ho sakta hai.
6.​ Testosterone (टे स्टोस्टे रोन):
○​ Gland: Testes (वष ृ ण), ovaries (thoda sa), adrenal glands.
○​ Kaam: Male sexual development (परु ु ष यौन विकास), muscle mass (मांसपेशियों का
विकास), bone density (हड्डियों का घनत्व), libido (कामेच्छा) (both sexes mein).
Aggression (आक्रामकता) aur mood par bhi asar daal sakta hai.
7.​ Insulin (इंसलिु न):
○​ Gland: Pancreas (अग्न्याशय).
○​ Kaam: Blood sugar levels ko control karta hai by helping glucose enter cells.
Energy regulation.
8.​ Leptin (लेप्टिन):
○​ Gland: Fat cells (वसा कोशिकाएं).
○​ Kaam: Appetite suppressant (भख ू कम करने वाला). Brain ko signal deta hai ki body
mein sufficient fat stores hain.
9.​ Ghrelin (घ्रेलिन):
○​ Gland: Stomach (पेट).
○​ Kaam: "Hunger hormone." Appetite stimulate karta hai (भख ू बढ़ाता है ).
Neurotransmitters aur Hormones ka Disorders mein Role:
Yeh general information hai, aur research abhi bhi chal rahi hai. Ek disorder mein kai factors
involved ho sakte hain.
1.​ Depression (अवसाद):
○​ Neurotransmitters:
■​ Serotonin (Low levels): Mood, anxiety, sleep, appetite par asar. SSRI
(Selective Serotonin Reuptake Inhibitor) dawaiyan iske level ko badhane ki
koshish karti hain.
■​ Norepinephrine (Low levels): Energy, alertness, motivation kam hona.
SNRI (Serotonin-Norepinephrine Reuptake Inhibitor) dawaiyan in dono par
kaam karti hain.
■​ Dopamine (Low levels): Pleasure, motivation, interest kam hona
(anhedonia). Kuch antidepressants dopamine system ko target karte hain.
○​ Hormones:
■​ Cortisol (High levels - HPA axis dysfunction): Chronic stress aur
depression mein HPA axis (Hypothalamic-Pituitary-Adrenal) overactive ho
sakta hai.
■​ Thyroid hormones (Low levels - Hypothyroidism): Depression jaise
symptoms de sakta hai.
■​ Estrogen (Fluctuations/Low levels): Postpartum depression, premenstrual
dysphoric disorder (PMDD), menopausal depression se link ho sakta hai.
2.​ Anxiety Disorders (चिंता विकार) (e.g., Generalized Anxiety Disorder, Panic Disorder,
Social Anxiety):
○​ Neurotransmitters:
■​ GABA (Low activity/dysfunction): GABA brain ko shant karta hai; iski kami
se anxiety badh sakti hai. Benzodiazepine dawaiyan (jaise Valium, Xanax)
GABA ke effect ko badhati hain.
■​ Serotonin (Imbalance): Mood aur anxiety dono ko regulate karta hai. SSRIs
anxiety mein bhi use hoti hain.
■​ Norepinephrine (Overactivity): "Fight or flight" system ka overactive hona
anxiety ke physical symptoms de sakta hai (tez heart rate, etc.).
■​ Glutamate (Overactivity): Excitatory hai, iski zyada activity bhi anxiety se
judi ho sakti hai.
○​ Hormones:
■​ Cortisol (High levels): Chronic stress aur anxiety HPA axis ko activate
rakhte hain.
■​ Adrenaline/Epinephrine (High levels): Panic attacks mein iska surge hota
hai.
3.​ Schizophrenia (सिज़ोफ्रेनिया):
○​ Neurotransmitters:
■​ Dopamine (Excess activity in some brain pathways - mesolimbic):
"Positive symptoms" (hallucinations, delusions) se link. Antipsychotic
dawaiyan dopamine D2 receptors ko block karti hain.
■​ Dopamine (Low activity in other brain pathways - mesocortical):
"Negative symptoms" (motivation ki kami, social withdrawal) aur cognitive
impairment se link ho sakta hai.
■​ Glutamate (Dysfunction - especially NMDA receptors): Ek important
theory hai ki NMDA receptor ki kam activity schizophrenia ke development
 mein role play karti hai.
■​ Serotonin (Imbalance): Atypical antipsychotics serotonin receptors par bhi
kaam karte hain.
■​ GABA (Dysfunction): GABAergic neurons ki kami ya dysfunction bhi paya
gaya hai.
○​ Hormones: Research ongoing; HPA axis dysfunction, sex hormone differences bhi
study kiye jaa rahe hain.
4.​ Bipolar Disorder (द्विध्रव
ु ी विकार):
○​ Neurotransmitters: Complex imbalance.
■​ Norepinephrine (High in mania, Low in depression).
■​ Dopamine (High in mania, Low in depression).
■​ Serotonin (Low in both phases, or dysregulated).
■​ Glutamate (Possible overactivity in mania).
■​ GABA (Possible underactivity).
○​ Hormones:
■​ Cortisol (HPA axis dysfunction): Stress ek trigger ho sakta hai.
■​ Thyroid hormones (Dysregulation): Mood swings se link. Melatonin (sleep
disturbance).
5.​ Parkinson's Disease (पार्किं संस रोग):
○​ Neurotransmitters:
■​ Dopamine (Severe loss): Substantia nigra (brain ka ek part) mein dopamine
banane wale neurons ka destruction. Motor symptoms (tremor, rigidity,
slowness) ka main कारण. Levodopa (L-DOPA) dawai dopamine mein convert
hoti hai.
■​ Acetylcholine (Relative excess due to dopamine loss): Tremor mein role.
■​ Norepinephrine, Serotonin (Loss): Non-motor symptoms (depression,
sleep problems) mein contribute kar sakte hain.
6.​ Alzheimer's Disease (अल्ज़ाइमर रोग):
○​ Neurotransmitters:
■​ Acetylcholine (Significant loss): Memory aur cognitive functions mein kami
ka bada कारण. Cholinesterase inhibitor dawaiyan ACh ko breakdown hone se
rokti hain.
■​ Glutamate (Excessive stimulation - excitotoxicity): NMDA receptors ki
overactivation se neuron damage ho sakta hai. Memantine (NMDA receptor
antagonist) use hota hai.
■​ Norepinephrine, Serotonin (Loss): Behavioral aur mood changes mein
contribute.
○​ Proteins: Beta-amyloid plaques aur Tau tangles (neurofibrillary tangles) hallmark
hain, jo neuron function ko disrupt karte hain.
7.​ ADHD (Attention-Deficit/Hyperactivity Disorder) (एडीएचडी):
○​ Neurotransmitters:
■​ Dopamine (Dysregulation/Low levels in PFC): Attention, motivation,
reward processing mein kami. Stimulant dawaiyan (jaise Ritalin, Adderall)
dopamine (aur norepinephrine) ke levels ko badhati hain.
■​ Norepinephrine (Dysregulation/Low levels in PFC): Alertness, attention,
executive functions mein kami.
○​ Hormones: Research ongoing; thyroid, cortisol par studies hain.
8.​ Sleep Disorders (e.g., Insomnia) (नींद संबधं ी विकार):
 ○​ Neurotransmitters:
■​ GABA (Low activity): Insomnia mein. Sleep medications GABA system ko
target karti hain.
■​ Serotonin (Imbalance): Sleep-wake cycle regulation.
■​ Norepinephrine, Dopamine, Histamine, Acetylcholine (High activity at
night): Yeh wakefulness promote karte hain, inki activity raat mein kam honi
chahiye.
■​ Orexin/Hypocretin (Excess or mistimed release for insomnia; Deficiency
in Narcolepsy): Wakefulness promote karta hai.
○​ Hormones:
■​ Melatonin (Low levels or delayed release): Circadian rhythm disruption.
Melatonin supplements use hote hain.
■​ Cortisol (High levels at night): Stress-induced insomnia.
9.​ Eating Disorders (e.g., Anorexia Nervosa, Bulimia Nervosa) (खान-पान संबध ं ी विकार):
○​ Neurotransmitters:
■​ Serotonin (Dysregulation): Appetite, mood, impulse control.
■​ Dopamine (Dysregulation): Reward system, motivation, food seeking
behavior.
■​ Norepinephrine (Imbalance).
○​ Hormones:
■​ Leptin (Altered levels): Appetite regulation.
■​ Ghrelin (Altered levels): Hunger signals.
■​ Cortisol (High in anorexia - starvation stress).
■​ Thyroid hormones (Often low in anorexia).
■​ Sex hormones (Often low in anorexia).
10.​Stress-Related Disorders (e.g., PTSD - Post-Traumatic Stress Disorder) (तनाव संबध ं ी
विकार):
○​ Neurotransmitters:
■​ Norepinephrine (Overactivity): Hyperarousal, flashbacks.
■​ Serotonin (Dysregulation).
■​ Dopamine (Dysregulation).
■​ GABA (Reduced function).
■​ Glutamate (Overactivity).
■​ Endocannabinoids (Dysregulation).
○​ Hormones:
■​ Cortisol (HPA axis dysregulation - can be complex, sometimes lower
baseline cortisol but exaggerated stress response).
■​ Adrenaline/Epinephrine (Increased reactivity).
Important Notes:
●​ Complexity: Disorders bahut complex hote hain. Sirf ek neurotransmitter ya hormone ki
kami ya ‫ زیادتی‬se nahi hote. Aksar multiple systems mein imbalance hota hai.
●​ Interaction: Neurotransmitters aur hormones aapas mein interact karte hain.
●​ Individual Differences: Har vyakti alag hota hai. Ek hi disorder mein alag-alag logo mein
thoda different imbalance ho sakta hai.
●​ Research: Yeh field abhi bhi research ka vishay hai aur hamari samajh badhti ja rahi hai.
Umeed hai yeh jaankari aapke liye faydemand hogi! Yeh competitive exams ke liye ek accha
overview hai.
Okay, so, yeh jo 12 cranial nerves hain, yeh brain ke alag-alag parts se nikalte hain. Mostly yeh
brainstem se aate hain, aur jo pehle do hain woh cerebrum se aate hain. Yahaan pe ek general
idea diya gaya hai ki yeh kahaan se originate hote hain aur kahaan tak jaate hain:
Origin from the Cerebrum:
●​ Olfactory Nerve (CN I): Yeh nikalta hai olfactory epithelium se jo nasal cavity mein hota
hai. Phir yeh cribriform plate se guzarta hai jo ethmoid bone mein hota hai, aur end hota
hai olfactory bulb mein, jo frontal lobe ke neeche waale surface pe hota hai. Iska kaam
hai smell karna.
●​ Optic Nerve (CN II): Yeh nikalta hai aankh ke retina se, optic canal se paas hota hai, aur
optic chiasm banaata hai. Chiasm se, optic tracts aage jaate hain lateral geniculate
nucleus of the thalamus tak (vision ke liye) aur doosri jagahon par bhi. Iska kaam hai
dekhna.
Origin from the Brainstem:
●​ Midbrain: 3. Oculomotor Nerve (CN III): Yeh midbrain ke front se nikalta hai. Yeh mostly
aankh ke extraocular muscles ko control karta hai, pupil ko chhota bada karta hai, aur
lens ko adjust karta hai. 4. Trochlear Nerve (CN IV): Yeh midbrain ke peeche se nikalta
hai (yeh ek hi cranial nerve hai jo dorsally nikalta hai). Yeh aankh ke superior oblique
muscle ko innervate karta hai.
●​ Pons: 5. Trigeminal Nerve (CN V): Yeh sabse bada cranial nerve hai, aur yeh pons ke
side se nikalta hai. Iski teen branches hain (ophthalmic, maxillary, aur mandibular) jo face,
cornea, nasal aur oral cavities mein sensation ke liye responsible hain, aur muscles of
mastication (chabane waale muscles) ko control karta hai. 6. Abducens Nerve (CN VI):
Yeh pons aur medulla ke beech ke junction se nikalta hai. Yeh aankh ke lateral rectus
muscle ko innervate karta hai, jo abduction (bahar ki taraf movement) ke liye responsible
hai. 7. Facial Nerve (CN VII): Yeh pons se nikalta hai, cerebellopontine angle ke paas.
Yeh facial expressions ko control karta hai, tongue ke aage ke do-tihaai hisse se taste feel
karta hai, lacrimation (aansu) aur salivation (thook) ko control karta hai. 8.
Vestibulocochlear Nerve (CN VIII): Yeh bhi pons se nikalta hai, cerebellopontine angle
par. Iski do branches hain: vestibular nerve (balance aur spatial orientation ke liye) aur
cochlear nerve (hearing ke liye).
●​ Medulla Oblongata: 9. Glossopharyngeal Nerve (CN IX): Yeh medulla ke side se
nikalta hai. Yeh tongue ke peeche ke ek-tihaai hisse se taste feel karta hai, swallowing
(nigalne) mein help karta hai, salivation (parotid gland se) aur blood pressure aur blood
gases ko monitor karta hai. 10. Vagus Nerve (CN X): Yeh medulla ke peeche se nikalta
hai. Yeh ek bada parasympathetic nerve hai, jo thorax aur abdomen ke organs ko
innervate karta hai. Yeh heart rate, digestion, awaaz nikalne aur bahut si cheezon mein
involved hai. 11. Accessory Nerve (CN XI): Iske do parts hain: cranial root (jo medulla se
nikalta hai) aur spinal root (jo upper spinal cord se aata hai). Yeh parts judte hain aur phir
alag ho jaate hain. Cranial root vagus nerve mein contribute karta hai aur spinal root
sternocleidomastoid aur trapezius muscles (gardan aur shoulder movement) ko innervate
karta hai. 12. Hypoglossal Nerve (CN XII): Yeh medulla ke front se nikalta hai. Yeh
tongue ke muscles ko control karta hai, jo speech aur swallowing ke liye bahut important
hai.
In summary:
●​ Cerebrum: CN I, CN II
●​ Midbrain: CN III, CN IV
●​ Pons: CN V, CN VI, CN VII, CN VIII
●​ Medulla Oblongata: CN IX, CN X, CN XI (cranial root), CN XII
 ●​ Spinal Cord: CN XI (spinal root)
Phir yeh cranial nerves skull se alag-alag foramina (openings) se bahar nikalte hain aur apni
target destinations tak pahunchte hain, jo head, neck aur trunk mein hote hain (vagus nerve ke
case mein).
Okay, let's break down these topics one by one with all the details you need!
1. Pain Relief Neurotransmitters (दर्द निवारक न्यरू ोट्रांसमीटर)
●​ Kya hain? Yeh woh chemical messengers hain jo hamare nervous system mein pain
signals ko kam karne ya block karne mein madad karte hain. Yeh natural pain killers ki
tarah kaam karte hain.
●​ Mukhya Neurotransmitters (Main Neurotransmitters):
○​ Endorphins (एंडोर्फि न): Yeh natural opioids hain jo exercise (runner's high), stress,
ya pain ke response mein release hote hain. Yeh pain perception ko kam karte hain
aur feeling of well-being create karte hain. Hans Kosterlitz aur John Hughes ne
1970s mein endorphins ki khoj ki thi.
○​ Enkephalins (एनकेफेलिन): Yeh bhi opioid peptides hain aur pain modulation mein
involve hote hain. Yeh spinal cord aur brain mein pain signals ke transmission ko
inhibit karte hain. Endorphins ke saath milkar kaam karte hain.
○​ Serotonin (सेरोटोनिन): Yeh neurotransmitter mood regulation, sleep, appetite ke
saath-saath pain perception ko bhi modulate karta hai. Kuch pain relief medications
serotonin ke levels ko badhakar kaam karti hain. Vittorio Erspamer ne 1930s mein
iski khoj ki thi.
○​ Norepinephrine (नॉरएपिनेफ्रीन): Yeh "fight-or-flight" response se juda hai, lekin yeh
pain pathways ko bhi affect karta hai. Spinal cord mein pain signals ko block karne
mein madad karta hai. Ulf von Euler ne iski khoj ki thi.
○​ GABA (गाबा - Gamma-Aminobutyric Acid): Yeh ek inhibitory neurotransmitter hai
jo overall nervous system activity ko kam karta hai, jismein pain signals bhi shamil
hain. Pain se associated anxiety aur muscle tension ko kam karne mein madad
karta hai. Eugene Roberts aur Jorge Awapara ne iski khoj ki thi.
●​ Mechanism of Action: Yeh neurotransmitters pain signals ko brain tak pahunchne se
pehle spinal cord level par ya brain mein hi inhibit karte hain. Yeh pain pathways mein
receptors se bind hokar unki activity ko kam karte hain.
2. Action Potentials (क्रिया विभव) - Pre, During, and Post
Action potential ek neuron mein hone wala ek brief electrical event hai jo information ko ek cell
se doosre cell tak pahunchane ke liye zaroori hai.
●​ Pre-Action Potential (Action Potential se Pehle): Resting Potential (विश्राम विभव)
○​ Neuron resting state mein hota hai.
○​ Cell membrane ke across ek electrical potential difference hota hai, jise resting
membrane potential kehte hain (usually around -70 mV).
○​ Yeh difference ion concentration mein antar ke karan hota hai:
■​ Zyada concentration of Potassium ions (K+) andar ki taraf.
■​ Zyada concentration of Sodium ions (Na+) aur Chloride ions (Cl-) bahar ki
taraf.
○​ Sodium-potassium pump active rehta hai aur 3 Na+ ions ko bahar aur 2 K+ ions ko
andar pump karta hai, jisse negative charge andar maintain rehta hai.
○​ Membrane potassium ke liye zyada permeable hota hai isliye K+ ions leak out karte
hain, contributing to the negative resting potential.
●​ During Action Potential (Action Potential ke Dauran): Depolarization and
Repolarization (ध्रव ु ीकरण और पनु :ध्रव
ु ीकरण)
○​ Depolarization (ध्रव ु ीकरण):
■​ Jab ek stimulus (electrical, chemical, etc.) neuron tak pahunchta hai aur
membrane potential ek threshold (-55 mV ke kareeb) tak pahunchta hai, toh
voltage-gated sodium channels khulte hain.
 ■​ Na+ ions cell ke andar tezi se rush karte hain kyunki andar negative charge
hai aur bahar unki concentration zyada hai.
■​ Is influx ke karan andar ka charge positive ho jata hai (around +30 mV). Yeh
depolarization phase hai.
○​ Repolarization (पन ु :ध्रव
ु ीकरण):
■​ Sodium channels turant band ho jaate hain.
■​ Voltage-gated potassium channels dheere-dheere khulte hain.
■​ K+ ions ab cell se bahar rush karte hain kyunki andar positive charge hai aur
bahar unki concentration kam hai.
■​ Potassium ke efflux ke karan andar ka charge wapas negative hone lagta hai,
aur membrane potential resting level ki taraf laut aata hai. Yeh repolarization
phase hai.
●​ Post-Action Potential (Action Potential ke Baad): Hyperpolarization and Return to
Resting Potential (अतिध्रव ु ीकरण और विश्राम विभव पर वापसी)
○​ Hyperpolarization (अतिध्रव ु ीकरण):
■​ Potassium channels thoda dheere band hote hain, jiske karan membrane
potential briefly resting level se bhi zyada negative ho jata hai (e.g., -75 mV).
Yeh hyperpolarization phase hai. Is dauran neuron ek aur action potential fire
karne ke liye kam sensitive hota hai (refractory period).
○​ Return to Resting Potential (विश्राम विभव पर वापसी):
■​ Voltage-gated potassium channels poori tarah se band ho jaate hain.
■​ Sodium-potassium pump apna kaam jari rakhta hai, ions ki sahi concentration
gradient ko restore karta hai.
■​ Membrane potential wapas resting level (-70 mV) par aa jata hai aur neuron
next stimulus ke liye taiyar ho jata hai.
3. Transfer in Synapse Process (सिनैप्स प्रक्रिया में स्थानांतरण)
Synapse do neurons ke beech ya ek neuron aur ek target cell (jaise muscle ya gland) ke beech
ka junction hai jahan chemical ya electrical signals pass hote hain. Chemical synapse zyada
common hai.
●​ Presynaptic Neuron (प्रीसिनैप्टिक न्यरू ॉन): Yeh woh neuron hai jo signal bhej raha hai.
1.​ Action Potential Arrival: Jab action potential presynaptic neuron ke axon terminal
tak pahunchta hai.
2.​ Calcium Ion Influx (कैल्शियम आयन अंतर्वाह): Voltage-gated calcium channels axon
terminal membrane mein khulte hain. Calcium ions (Ca2+) bahar se andar rush
karte hain.
3.​ Neurotransmitter Release (न्यरू ोट्रांसमीटर रिहाई): Calcium influx synaptic vesicles
(jinmein neurotransmitters hote hain) ko presynaptic membrane ke saath fuse karne
aur neurotransmitters ko synaptic cleft (do neurons ke beech ka gap) mein release
karne ka karan banta hai. Yeh process exocytosis kehlata hai.
●​ Synaptic Cleft (सिनैप्टिक दरार): Yeh do neurons ke beech ka chota sa gap (around 20-40
nanometers) hai jahan neurotransmitters diffuse karte hain.
●​ Postsynaptic Neuron (पोस्टसिनैप्टिक न्यरू ॉन): Yeh woh neuron hai jo signal receive kar
raha hai.
1.​ Neurotransmitter Binding (न्यरू ोट्रांसमीटर बंधन): Neurotransmitters synaptic cleft ko
cross karte hain aur postsynaptic membrane par specific receptor proteins se bind
hote hain.
2.​ Ion Channel Opening (आयन चैनल खल ु ना): Neurotransmitter ka receptor se bind
hona postsynaptic membrane mein ion channels ko khol ya band kar sakta hai.
 ■​ Agar Sodium (Na+) channels khulte hain, toh Na+ andar aate hain aur
postsynaptic neuron depolarize ho sakta hai, jisse Excitatory Postsynaptic
Potential (EPSP) create hota hai, jo action potential fire karne ki probability
badhata hai.
■​ Agar Potassium (K+) channels khulte hain ya Chloride (Cl-) channels andar
aate hain, toh postsynaptic neuron hyperpolarize ho sakta hai, jisse
Inhibitory Postsynaptic Potential (IPSP) create hota hai, jo action potential
fire karne ki probability kam karta hai.
3.​ Signal Termination (सिग्नल समाप्ति): Neurotransmitter ka effect jaldi se terminate
hona zaroori hai taaki naya signal transmit ho sake. Yeh teen tarikon se hota hai:
■​ Diffusion (विसरण): Neurotransmitters synaptic cleft se door diffuse ho jaate
hain.
■​ Enzymatic Degradation (एंजाइमेटिक क्षरण): Specific enzymes synaptic cleft
mein neurotransmitters ko break down kar dete hain (e.g.,
acetylcholinesterase acetylcholine ko break down karta hai).
■​ Reuptake (पन ु र्ग्रहण): Presynaptic neuron ke axon terminal ya surrounding
glial cells mein specific transporter proteins neurotransmitters ko wapas le
lete hain, jahan unhe recycle kiya ja sakta hai ya degrade kiya ja sakta hai.
4. Names of Reflexes in Infants (शिशओ ु ं में सजग क्रियाओं के नाम)
Infants mein bahut saare reflexes hote hain jo unke survival aur development ke liye zaroori
hain. Yeh reflexes usually pehle kuch mahino mein disappear ho jaate hain jab voluntary control
develop hota hai. Kuch important reflexes hain:
●​ Rooting Reflex (रूटिंग रिफ्लेक्स): Jab infant ke gaal ya lips ko stroke kiya jata hai, toh woh
apna sir us direction mein turn karta hai aur apna munh kholta hai, jaise ki nipple ko
dhoondh raha ho.
●​ Sucking Reflex (सकिंग रिफ्लेक्स): Jab infant ke munh mein koi cheez rakhi jaati hai (jaise
nipple ya finger), toh woh use sookhne lagta hai.
●​ Grasping Reflex (ग्रैस्पिग ं रिफ्लेक्स): Jab infant ke palm mein koi cheez rakhi jaati hai, toh
woh use tight grip se pakad leta hai.
●​ Moro Reflex (मोरो रिफ्लेक्स) / Startle Reflex (स्टार्टल रिफ्लेक्स): Jab infant suddenly tez
aawaz sunta hai ya use lagta hai ki woh gir raha hai, toh woh apni baahein phaila leta hai
aur phir unhe wapas andar ki taraf laata hai, jaise gale laga raha ho.
●​ Babinski Reflex (बैबिस् ं की रिफ्लेक्स): Jab infant ke paon ke sole ko heel se toes tak stroke
kiya jata hai, toh bade toe upar ki taraf bend hota hai aur baaki toes fan out ho jaate hain.
Adults mein, toes curl down karte hain.
●​ Stepping Reflex (स्टे पिग ं रिफ्लेक्स) / Walking Reflex (वॉकिंग रिफ्लेक्स): Jab infant ko
seedha pakad kar unke paon kisi surface ko touch karte hain, toh woh walking ya dancing
movements karte hain.
●​ Tonic Neck Reflex (टॉनिक नेक रिफ्लेक्स) / Fencer Position (फेंसर पोजीशन): Jab infant ka
sir ek taraf turn kiya jata hai, toh us taraf ki baanh seedhi ho jaati hai aur doosri taraf ki
baanh bend ho jaati hai, jaise ki woh fencing kar raha ho.
●​ Swallowing Reflex (निगलने की सजग क्रिया): Infant automatic tarike se liquid ko nigal sakta
hai.
5. Health Action Process Approach (HAPA) (स्वास्थ्य क्रिया प्रक्रिया दृष्टिकोण)
Yeh ek social-cognitive model hai jo health behaviors ko explain aur predict karta hai. Yeh do
main phases par focus karta hai:
●​ Motivational Phase (प्रेरक चरण): Is phase mein log ek health behavior ko adopt karne ki
intention develop karte hain. Yeh intention teen beliefs par depend karti hai:
 ○​ Risk Perception (जोखिम धारणा): Kisi health threat ke liye individual ka perceived
vulnerability. (Kya mujhe yeh bimari hone ka khatra hai?)
○​ Outcome Expectancies (परिणाम प्रत्याशा): Behavior ke potential positive ya
negative consequences ke baare mein individual ki beliefs. (Agar main yeh
behavior karta hoon toh kya fayde/nuksan honge?)
○​ Self-Efficacy (आत्म-प्रभावकारिता): Specific health behavior ko successfully perform
karne ki individual ki confidence. (Kya main is behavior ko kar sakta hoon?)
○​ Intention Formation (इच्छा गठन): Jab risk perception zyada hoti hai, positive
outcome expectancies hote hain, aur self-efficacy strong hoti hai, toh individual
behavior ko adopt karne ki intention banata hai.
●​ Volitional Phase (स्वैच्छिक चरण) / Action Phase (क्रिया चरण): Is phase mein intention ko
actual behavior mein translate kiya jata hai. Ismein shamil hain:
○​ Planning (योजना): Goal setting, action planning (kab, kahan, kaise behavior karna
hai), aur coping planning (obstacles ko kaise handle karna hai).
○​ Action Control (क्रिया नियंत्रण): Self-monitoring, self-regulatory skills, aur feedback
mechanism jo behavior ko maintain karne mein madad karte hain.
○​ Maintenance (रखरखाव): Behavior ko long-term tak continue rakhna aur relapse se
bachna.
○​ Recovery (पन ु र्प्राप्ति): Agar relapse ho jaaye toh wapas behavior ko adopt karna.
Key Figures: Ralf Schwarzer ne Health Action Process Approach ko develop kiya tha.
6. Complex and Simple Cell in Visual Cortex (दृश्य प्रांतस्था में जटिल और सरल कोशिकाएं)
Yeh visual cortex (brain ka woh hissa jo visual information process karta hai) mein neurons ki
types hain jo visual stimuli ke specific features ke liye respond karti hain. Inki khoj David Hubel
aur Torsten Wiesel ne ki thi, jiske liye unhe Nobel Prize mila tha.
●​ Simple Cells (सरल कोशिकाएं):
○​ Response: Simple cells visual field mein specific orientation aur position wale lines
ya edges ke liye sabse zyada strongly respond karti hain.
○​ Receptive Fields: Inke receptive fields (visual field ka woh area jise stimulate
karne par cell fire karta hai) mein excitatory aur inhibitory zones hote hain jo parallel
lines ya edges ke roop mein arranged hote hain.
○​ Example: Ek simple cell vertical line ke liye tab sabse zyada fire karegi jab woh line
uske receptive field ke specific location par vertically oriented ho. Agar line tilted ho
ya position badle toh response kam ho jaata hai.
●​ Complex Cells (जटिल कोशिकाएं):
○​ Response: Complex cells bhi specific orientation wale lines ya edges ke liye
respond karti hain, lekin inki response position ke liye zyada invariant hoti hai. Yeh
tab bhi respond karti hain jab line apne receptive field mein move kar rahi ho.
○​ Receptive Fields: Inke receptive fields mein excitatory aur inhibitory zones nahi
hote hain jo fixed position par ho. Yeh zyada diffuse hote hain.
○​ Input: Complex cells ko simple cells se input milta hai jinki similar orientation
preference hoti hai lekin slightly different receptive field positions hoti hain.
○​ Example: Ek complex cell vertical line ke liye tab bhi fire karegi agar woh line uske
receptive field mein upar ya neeche move kar rahi ho.
Hierarchy: Visual information retina se lateral geniculate nucleus (LGN) tak jaati hai, aur phir
visual cortex (V1) mein pahunchti hai. V1 mein simple cells hoti hain, aur complex cells ko
simple cells se input milta hai. Higher visual areas mein aur bhi zyada complex cells hoti hain jo
aur bhi abstract features (jaise shapes, faces, motion) ke liye respond karti hain.
7. Postsynaptic Potential Summation Control (पोस्टसिनैप्टिक विभव योग नियंत्रण)
Postsynaptic potentials (PSPs) postsynaptic neuron mein neurotransmitter ke bind hone ke
baad hone wale voltage changes hain. Yeh excitatory (EPSP) ya inhibitory (IPSP) ho sakte hain.
Ek postsynaptic neuron bahut saare presynaptic neurons se input receive karta hai, aur woh
decide karta hai ki action potential fire karna hai ya nahi yeh PSPs ke summation par depend
karta hai.
●​ Summation (योग): PSPs add up hote hain ek dusre ke saath postsynaptic neuron ke
axon hillock par (woh jagah jahan action potential initiate hota hai). Do tarike se
summation ho sakta hai:
○​ Temporal Summation (अस्थायी योग): Agar ek hi presynaptic neuron se bahut
jaldi-jaldi successive action potentials aate hain, toh unke dwara cause kiye gaye
PSPs ek dusre ke upar add ho jaate hain. Agar combined effect threshold tak
pahunchta hai toh action potential fire ho sakta hai.
○​ Spatial Summation (स्थानिक योग): Agar ek hi time par alag-alag presynaptic
neurons se PSPs aate hain aur woh postsynaptic neuron ke different synapses par
hote hain, toh yeh PSPs bhi axon hillock par add ho sakte hain. Agar combined
effect threshold tak pahunchta hai toh action potential fire ho sakta hai.
●​ Control (नियंत्रण): Summation postsynaptic neuron ko incoming signals ko integrate aur
process karne ka ek tareeka provide karta hai. Yeh is baat par control rakhta hai ki kab
action potential fire hoga.
○​ Excitatory aur Inhibitory Balance: Agar excitatory inputs inhibitory inputs se
zyada strong hote hain aur unka summation threshold tak pahunchta hai, toh action
potential fire hoga. Agar inhibitory inputs zyada strong hote hain toh action potential
fire hone ki probability kam ho jaati hai.
○​ Neural Computation: Summation neuron ko ek simple computational device ki
tarah kaam karne deta hai, jo multiple inputs ko combine karke ek output (action
potential ya nahi) decide karta hai.
8. Osmoreceptor (ऑस्मोरिसेप्टर)
Osmoreceptors special sensory receptors hain jo body fluids (mainly blood plasma) ki
osmolarity (solute concentration) mein changes ko detect karte hain. Yeh mainly hypothalamus
mein located hote hain, brain ka woh hissa jo homeostasis (internal balance) ko regulate karta
hai.
●​ Mechanism: Jab blood osmolarity badhti hai (dehydration ki wajah se), toh
osmoreceptors shrink ho jaate hain kyunki unse pani bahar nikal jaata hai. Yeh shrinkage
unmein electrical activity ko badhata hai, jisse hypothalamus mein neurons fire hote hain.
●​ Functions: Osmoreceptors body ke fluid balance ko maintain karne mein crucial role play
karte hain:
○​ Thirst Sensation (प्यास की अनभ ु ति
ू ): Hypothalamus mein osmoreceptors ki activity
thirst ki sensation ko trigger karti hai, jisse hum paani peete hain.
○​ Antidiuretic Hormone (ADH) Release (एंटीडाययरू े टिक हार्मोन (एडीएच) रिहाई):
Osmoreceptors posterior pituitary gland ko ADH release karne ke liye stimulate
karte hain. ADH kidney ko zyada paani ko absorb karne ke liye signal deta hai, jisse
urine production kam hota hai aur body mein paani conserve hota hai.
○​ Jab blood osmolarity kam hoti hai (zyada paani peene se), toh osmoreceptors swell
ho jaate hain, jisse thirst kam hoti hai aur AD
Okay, let's clarify the concepts of agonists and antagonists, especially in the context of
neurotransmitters and receptors.
Agonist (अगोनिस्ट)
●​ Kya hai? An agonist is a substance (it could be a neurotransmitter, a drug, or another
molecule) that binds to a receptor and activates it, producing a biological response. Think
of it like a key that fits into a lock (the receptor) and turns it, thereby opening the door
(causing an effect).
●​ Kaise kaam karta hai? Agonists mimic the action of the body's natural ligands (like
neurotransmitters or hormones). They have an affinity for the receptor (they can bind to
it) and efficacy (they can activate it and produce a response).
●​ Types of Agonists:
○​ Full Agonist: Produces the maximal possible response from the receptor.
○​ Partial Agonist: Binds to the receptor but produces a submaximal response, even
when all receptors are occupied. It has affinity but lower efficacy than a full agonist.
It can sometimes act as an antagonist in the presence of a full agonist.
○​ Inverse Agonist: Binds to a receptor and produces an effect opposite to that of a
conventional agonist. This is usually seen with receptors that have some baseline
activity even without a ligand bound.
●​ Examples:
○​ Neurotransmitters: Acetylcholine is an agonist at acetylcholine receptors.
Dopamine is an agonist at dopamine receptors. Serotonin is an agonist at serotonin
receptors.
○​ Drugs:
■​ Morphine: An opioid receptor agonist used for pain relief. It mimics the action
of endorphins.
■​ Albuterol: A beta-2 adrenergic receptor agonist used to treat asthma by
widening airways. It mimics the action of epinephrine.
■​ Nicotine: An agonist at nicotinic acetylcholine receptors.
Antagonist (प्रतिपक्षी)
●​ Kya hai? An antagonist is a substance that binds to a receptor but does not activate it.
Instead, it blocks or inhibits the action of agonists by preventing them from binding to
the receptor. Think of it like a key that fits into the lock but doesn't turn it, and also
prevents the correct key from being inserted.
●​ Kaise kaam karta hai? Antagonists have an affinity for the receptor (they can bind to it)
but have no efficacy (they cannot activate it to produce a response).
●​ Types of Antagonists:
○​ Competitive Antagonist: Binds to the same site on the receptor as the agonist.
The effect of a competitive antagonist can be overcome by increasing the
concentration of the agonist (it's a competition for the binding site).
○​ Non-competitive Antagonist: Binds to a different site on the receptor (allosteric
site) or binds irreversibly to the same site. This can change the shape of the
receptor or permanently block the agonist binding site, making it difficult or
impossible for the agonist to produce its effect, even at high concentrations. The
maximal response of the agonist is usually reduced.
●​ Examples:
○​ Drugs:
■​ Naloxone: An opioid receptor antagonist used to reverse opioid overdoses. It
blocks the effects of opioids like heroin and morphine.
 ■​ Beta-blockers (e.g., Propranolol, Metoprolol): Antagonists at
beta-adrenergic receptors, used to treat high blood pressure and anxiety by
blocking the effects of adrenaline and noradrenaline.
■​ Cetirizine (Zyrtec): An antagonist at histamine (H1) receptors, used to treat
allergies by blocking the effects of histamine.
■​ Atropine: A competitive antagonist of muscarinic acetylcholine receptors.
In Simple Terms:
●​ Agonist = Activator: Turns the receptor "on" and causes a response.
●​ Antagonist = Blocker: Turns the receptor "off" or prevents it from being turned "on" by
an agonist.
Understanding the interplay between agonists and antagonists is crucial in pharmacology and
neuroscience for developing drugs that can either enhance or block specific biological
processes.