What are the three main parts of a neuron?	Dendrites (receive signals), cell body/soma (contains nucleus), and axon (transmits signals away from the cell body).
What is the myelin sheath?	A fatty insulating layer around axons that speeds up neural impulse transmission via saltatory conduction.
What is an action potential?	A brief electrical charge that travels down the axon when the neuron fires, following the all-or-none principle.
What is the all-or-none principle?	A neuron either fires at full strength or does not fire at all; there is no partial firing.
What happens at the synapse during neural transmission?	Neurotransmitters are released from the presynaptic neuron's terminal buttons, cross the synaptic cleft, and bind to receptors on the postsynaptic neuron.
What is reuptake?	The process by which neurotransmitters are reabsorbed by the presynaptic neuron, ending their effect on the postsynaptic neuron.
What does the neurotransmitter serotonin regulate?	Mood, sleep, appetite, and arousal. Low serotonin levels are linked to depression.
What is the function of dopamine?	Involved in reward, motivation, movement, and pleasure. Excess dopamine is associated with schizophrenia; deficiency is linked to Parkinson's disease.
What does acetylcholine (ACh) do?	Enables muscle contraction and plays a role in learning and memory. Its deficit is associated with Alzheimer's disease.
What is the role of GABA?	The major inhibitory neurotransmitter in the brain. It reduces neural activity; low GABA levels are linked to anxiety disorders.
What are endorphins?	Natural opioid neurotransmitters that reduce pain perception and produce feelings of pleasure or euphoria.
What are the two main divisions of the nervous system?	The central nervous system (brain and spinal cord) and the peripheral nervous system (all other nerves).
What are the two branches of the autonomic nervous system?	Sympathetic (activates fight-or-flight response) and parasympathetic (calms the body to rest-and-digest).
What does the frontal lobe control?	Executive functions including reasoning, planning, judgment, voluntary movement (motor cortex), and speech production (Broca's area).
What is the function of the temporal lobe?	Processes auditory information and is involved in language comprehension (Wernicke's area) and memory formation.
What does the parietal lobe do?	Processes somatosensory information (touch, pressure, temperature, pain) via the somatosensory cortex.
What is the function of the occipital lobe?	Processes visual information. Damage to this area can cause cortical blindness.
What does the hippocampus do?	Essential for forming new explicit (declarative) memories. Damage results in an inability to create new long-term memories.
What is the role of the amygdala?	Processes emotions, especially fear and aggression. It plays a key role in emotional memory and the fight-or-flight response.
What does the thalamus do?	The brain's sensory relay station — it routes incoming sensory information (except smell) to the appropriate cortical areas.
What is the function of the cerebellum?	Coordinates voluntary movement, balance, and motor learning. It fine-tunes motor activity rather than initiating it.
What is Broca's area vs. Wernicke's area?	Broca's area (left frontal lobe) controls speech production; Wernicke's area (left temporal lobe) controls language comprehension. Damage to either causes a distinct type of aphasia.
What are fMRI and PET scans used for?	fMRI detects brain activity by measuring blood flow changes; PET scans track radioactive glucose to show which brain areas are most active. Both are functional imaging techniques.