Lecture 2: Synaptic Function and Psychopharmacology

Excitatory Post-Synaptic Potentials (EPSPs)

Depolarize the post-synaptic membrane and increase the likelihood of an action potential. Example:Glutamate typically causes EPSPs.

Inhibitory Post-Synaptic Potentials (IPSPs)

Hyperpolarize the post-synaptic membrane and decrease the likelihood of an action potential. Example:GABA typically causes IPSPs.

Temporal Summation

Multiple signals from the same neuron in rapid succession can trigger an action potential if the threshold is reached.

Spatial Summation

Signals from multiple neurons received simultaneously can trigger an action potential if the threshold is reached.

Neurotransmitters (NT)

Chemical messengers like Acetylcholine (ACh), Noradrenaline (NA), Dopamine (DA), 5-Hydroxytryptamine (Serotonin), and Gamma-Aminobutyric Acid (GABA) that play crucial roles in brain function.

Agonists

Drugs that mimic the action of neurotransmitters by binding to receptors. Example:Nicotine is an agonist for acetylcholine receptors.

Antagonists

Drugs that inhibit the action of neurotransmitters by binding to receptors. Example:Naloxone is an antagonist for opioid receptors.

Inverse Agonists

Bind to the same receptor as an agonist but induce the opposite effect.

Psychoactive Drugs

Substances that affect the brain, altering mood, perception, or consciousness, including stimulants, depressants, and hallucinogens.

Parkinson’s Disease

Neurological disorder with symptoms like tremors, rigidity, and cognitive effects due to dopaminergic neuron degeneration in the substantia nigra.

Alzheimer’s Disease

Neurodegenerative disorder characterized by ACh-secreting neuron degeneration in the basal nucleus, leading to memory loss and cognitive decline.