Week 3: Brain and Behaviour

Action potential

An electrical signal that moves down a neuron's axon.

Agonist

A drug that mimics or strengthens a neurotransmitter's effects.

All-or-none

A neuron either reaches threshold and fires or does not fire.

Amygdala

A limbic structure involved in emotion and emotional memories.

Antagonist

A drug that blocks or impedes a neurotransmitter's normal activity.

Association cortex

Cortical areas that combine information for complex processing.

Auditory cortex

Temporal-lobe cortex responsible for processing auditory information.

Autonomic nervous system

Controls internal organs and glands.

Axon

The major extension of a neuron's soma that sends signals.

Broca's area

A left-hemisphere region essential for language production.

Central nervous system (CNS)

The brain and spinal cord.

Central sulcus

A deep groove separating the frontal and parietal lobes from the temporal lobe.

Cerebellum

Controls balance, coordination, movement, motor skills, and some memory.

Cerebral cortex

The brain's outer surface associated with higher mental abilities.

Computerized tomography (CT) scan

An imaging technique using multiple X-rays combined by a computer.

Contralateral

Located on the opposite side of the body from a structure.

Corpus callosum

A thick band of neural fibers connecting the two brain hemispheres.

Degradation

Enzymes break neurotransmitters into components so they cannot bind receptors.

Dendrite

A branch-like part of a neuron that receives incoming signals.

Electroencephalography (EEG)

A method that records brain electrical activity using scalp electrodes.

Fight-or-flight response

Sympathetic activation that prepares the body to confront or escape a threat.

Forebrain

The largest brain division, including the cortex, thalamus, and limbic system.

Frontal lobe

Responsible for reasoning, motor control, emotion, and language; contains the motor cortex.

Frontal lobe syndrome

Symptoms from frontal-lobe damage affecting motivation, planning, behavior, and speech.

Functional magnetic resonance imaging (fMRI)

An MRI technique showing changes in brain metabolic activity over time.

Glial cell

Cells supporting neurons through insulation, communication, and nutrient/waste transport.

Gyrus

A bump or ridge on the cerebral cortex.

Hemisphere

The left or right half of the brain.

Hindbrain

A brain division containing the medulla, pons, and cerebellum.

Hippocampus

A temporal-lobe structure associated with learning and memory.

Homeostasis

Maintaining biological conditions at optimal, stable levels.

Homunculus

A figure showing how much cortical space represents different body parts.

Hypothalamus

Regulates homeostasis, sexual motivation, and communication with the endocrine system.

Lateralization

The specialization of different functions between the two hemispheres.

Limbic system

A group of structures involved in emotion and memory.

Longitudinal fissure

A deep groove separating the brain's two hemispheres.

Magnetic resonance imaging (MRI)

An imaging technique using magnetic fields to produce tissue images.

Medulla

Controls automatic functions such as breathing, blood pressure, and heart rate.

Midbrain

The brain division between the forebrain and hindbrain; contains the reticular formation.

Motor cortex

Cortical area involved in planning and coordinating movement.

Myelin sheath

A fatty substance that insulates axons.

Neuron

A nervous-system cell that processes and transmits information.

Neuroplasticity

The nervous system's ability to change.

Neurotransmitter

A chemical messenger of the nervous system.

Nodes of Ranvier

Open spaces between sections of the myelin sheath along an axon.

Occipital lobe

Responsible for visual processing; contains the primary visual cortex.

Parasympathetic nervous system

The division associated with routine, day-to-day body functions.

Parietal lobe

Processes sensory and perceptual information; contains the somatosensory cortex.

Peripheral nervous system (PNS)

The system connecting the CNS to muscles, organs, and senses.

Pituitary gland

Secretes hormones regulating body fluids and other endocrine glands.

Pons

Connects the brain and spinal cord and helps regulate sleep-related activity.

Positron emission tomography (PET) scan

Uses a radioactive tracer to monitor brain blood flow.

Prefrontal cortex

A frontal-lobe area responsible for higher-level cognitive functions.

Primary gustatory cortex

A cortical area responsible for processing information about taste/flavour.

Primary olfactory area

A frontal-lobe area responsible for processing information about smells.

Primary visual cortex

The occipital-lobe area responsible for processing visual information.

Psychotropic medication

Medication that treats psychiatric symptoms by affecting neurotransmitter systems.

Receptor

A protein on a cell where neurotransmitters attach.

Resting potential

The neuron's membrane state of readiness between signals.

Reuptake

The released neurotransmitter is pumped back into the neuron that released it.

Semipermeable membrane

A membrane allowing some molecules through while blocking others.

Soma

The cell body of a neuron.

Somatic nervous system

Relays sensory and motor information to and from the CNS.

Somatosensory cortex

Processes body sensations such as touch, temperature, and pain.

Somatotopy

The organized matching of body parts to their cortical representations.

Substantia nigra

A midbrain structure producing dopamine and involved in movement control.

Sulcus

A depression or groove in the cerebral cortex.

Sympathetic nervous system

Controls stress-related activities and prepares the body for action.

Synaptic cleft

The small gap between neurons where communication occurs.

Synaptic vesicle

A structure that stores neurotransmitters.

Temporal lobe

Associated with hearing, memory, emotion, and aspects of language.

Terminal button

An axon terminal containing synaptic vesicles.

Thalamus

Acts as a major sensory relay for the brain.

Threshold of excitation

The membrane charge level that causes a neuron to become active.

Ventral tegmental area (VTA)

A midbrain dopamine-producing structure linked to mood, reward, and addiction.

Wernicke's area

A brain region important for understanding speech.

Biological perspective

The view that psychological disorders can involve biological factors such as neurotransmitter imbalances.