36
🎯 Main Points

Chapter 36

PSYP610 - Neurological Bases of Behavior

🔑 Key Definitions

Acetylcholine (ACh): Neurotransmitter at neuromuscular junction and in brain; involved in muscle control, arousal, and memory
Glutamic Acid (Glutamate): Primary excitatory neurotransmitter in CNS; involved in learning and plasticity
GABA (Gamma-Aminobutyric Acid): Primary inhibitory neurotransmitter in CNS; 10-15 times more abundant than monoamines
Alzheimer's Disease: Neurodegenerative disorder with loss of cholinergic neurons; memory and cognitive decline

🧠 Acetylcholine (ACh)

  • Neuromuscular Junction: ACh is excitatory at skeletal muscles; causes contraction
  • Cardiac Muscle: ACh is inhibitory at heart; slows heart rate (vagus nerve)
  • Arousal: Cholinergic neurons in basal forebrain promote cortical activation and wakefulness
  • Memory: ACh critical for attention and memory formation
  • Alzheimer's Disease: Degeneration of cholinergic neurons in basal forebrain; treated with acetylcholinesterase inhibitors

🧠 Glutamic Acid (Glutamate)

  • Primary Excitatory NT: Most abundant excitatory neurotransmitter in brain
  • Learning & Plasticity: Critical for LTP (long-term potentiation) and memory formation
  • NMDA Receptors: Glutamate receptor type crucial for synaptic plasticity
  • Excitotoxicity: Excessive glutamate can kill neurons (stroke, trauma)

🧠 GABA (Gamma-Aminobutyric Acid)

  • Primary Inhibitory NT: Main inhibitory neurotransmitter throughout brain
  • Abundance: 10-15 times more GABA neurons than monoamine neurons
  • Anxiety: GABAergic drugs (benzodiazepines) reduce anxiety
  • Balance: GABA balances glutamate's excitation; prevents overexcitation

💡 Exam Tips

  • ACh has OPPOSITE effects: excitatory at muscles, inhibitory at heart
  • Alzheimer's = loss of ACh neurons; treat by blocking acetylcholinesterase
  • Glutamate = THE excitatory NT (not just "an" excitatory NT)
  • GABA = THE inhibitory NT; 10-15x more abundant than monoamines
  • Remember balance: Glutamate (excites) vs GABA (inhibits)
  • GABA drugs (benzodiazepines like Valium) treat anxiety by increasing inhibition