Chapter 2-The Biology of Mind

Vocabulary flashcards covering key terms from Chapter 2 notes on the Biology of Mind.

Neuron

The basic nerve cell of the nervous system that processes and transmits information via electrical and chemical signals.

Sensory neuron

A neuron that carries information from sensory receptors toward the central nervous system.

Motor neuron

A neuron that transmits signals from the CNS to muscles or glands to produce movement.

Mirror neuron

A neuron that fires when performing an action and when observing the same action performed by others.

Interneuron

A neuron that connects neurons within the central nervous system, facilitating communication between sensory and motor pathways.

Soma (cell body)

The cell body of a neuron that contains the nucleus and metabolic machinery.

Axon

The long fiber of a neuron that conducts electrical impulses away from the cell body.

Dendrite

Branchlike extensions that receive signals from other neurons and convey them to the soma.

Myelin sheath

Insulating layer around some axons that speeds up neural transmission.

Synapse

The junction between neurons where neurotransmitters are released to transmit signals.

Terminal button

The end of an axon that releases neurotransmitters into the synapse.

Action potential

A rapid, all-or-nothing electrical impulse that travels along the axon.

Neurotransmitter

Chemical messengers released at synapses to influence postsynaptic neurons.

Resting potential

The baseline electrical charge of a neuron when it is not firing (usually negative inside).

All-or-none law

Once threshold is reached, the action potential occurs fully; its amplitude is constant.

Nerve impulse

The propagated electrical signal along a neuron caused by action potentials.

Threshold

The level of depolarization required to trigger an action potential.

Brain plasticity (neuroplasticity)

The brain’s ability to reorganize its structure and function in response to experience, learning, or injury.

Neurogenesis

The growth of new neurons in certain brain regions.

Arborization

Growth and branching of dendrites and axons to form new neural connections.

Synaptogenesis

Formation of new synapses between neurons.

Central nervous system (CNS)

The brain and spinal cord; the body's processing and command center.

Peripheral nervous system (PNS)

All nerves outside the CNS that connect the CNS to the rest of the body.

Somatic nervous system

subdivision of the PNS that controls voluntary movements and transmits sensory information to the CNS.

Autonomic nervous system

Subdivision of the PNS that regulates involuntary bodily functions.

Sympathetic nervous system

Autonomic division that arouses the body in stressful situations (fight-or-flight).

Parasympathetic nervous system

Autonomic division that calms the body after stress (rest-and-digest).

Hindbrain

The oldest brain region, including the medulla, pons, and cerebellum, supporting basic life functions and coordination.

Limbic system

Emotion, motivation, memory; includes structures like the hippocampus and amygdala.

Forebrain

The most evolved brain region responsible for complex cognition, planning, language, and reasoning.

Brain evolution (hindbrain vs. forebrain)

Hindbrain is evolutionarily older; forebrain is newer and supports higher cognitive functions.

Hindbrain/Limbic/Forebrain processes

Hindbrain handles basic life support; limbic system handles emotion/memory; forebrain handles complex cognition.

Mike the headless chicken

A story used to illustrate brainstem control of basic life functions after decapitation and to discuss brain structure/function relationships.

Phineas Gage

Classic case showing frontal lobe damage can alter personality and executive function.

Frontal lobe

Part of the cerebral cortex involved in planning, decision making, impulse control, and personality.

Split-brain patient

A patient with severed corpus callosum, revealing hemispheric specialization and interhemispheric communication.

Right hemisphere

Often handles spatial and holistic processing; controls the left side of the body.

Left hemisphere

Often handles language and analytical processing; controls the right side of the body.

Cortical homunculus

Distorted map of the body on the sensory or motor cortex, showing disproportionate representation (e.g., hands, lips).

Somatosensory cortex

Cortical area that processes tactile and bodily sensory information.

Motor cortex

Cortical area that initiates voluntary motor movements.

Brain structure vs. brain function (tools)

Structure assessed with structural imaging (MRI/CT); function assessed with functional imaging/electrophysiology (fMRI, PET, EEG).

Tools for brain study

Structural imaging (MRI/CT), functional imaging (fMRI/PET), and electrophysiology (EEG) used to study brain.

Distortion in Figure 6.7

The cortical homunculus shows nonuniform body representation; some parts appear exaggerated in cortical maps.