Brain & Behavior Ch. 1

Neuron Doctrine

The concept that the neuron is an anatomical and physiological unit of the nervous system, composed of a cell body, dendrites, and axon, and that neurons are discrete cells not continuous with other cells.

Functional Zones of a Neuron

The four functional zones of a neuron are: input zone (dendrites), integration zone (cell body), conduction zone (axon), and output zone (axon terminals).

Motor Neurons

Neurons that carry signals from the CNS to muscles, facilitating movement and motor control.

Sensory Neurons

Neurons that detect sensory information from the environment and transmit it to the CNS.

Interneurons

Neurons that connect sensory and motor neurons within the CNS, playing a role in processing information and reflex arcs.

Multipolar Neurons

Neurons with one axon and many dendrites, which are the most common type.

Unipolar Neurons

Neurons with one axon that splits into two branches, primarily involved in sensory functions.

Bipolar Neurons

Neurons with one axon and one dendrite, often found in special sensory organs.

Synaptic Vesicles

Membrane-bound sacs in the presynaptic neuron that store neurotransmitters until they are released into the synaptic cleft.

Neurotransmitter Receptors

Molecules on the postsynaptic membrane that bind to neurotransmitters, initiating a response in the receiving neuron.

Dendritic Spine

Small, finger-like projections on dendrites that serve as primary sites for synaptic connections.

Neuroplasticity

The capacity for continual remodeling of connections between neurons; synapses and spines can come and go.

Axon Hillock

The conical structure at the beginning of an axon where action potentials are initiated.

Axon Collateral

Branches of an axon that allow a single neuron to communicate with multiple target cells.

Astrocytes

Supportive glial cells that maintain the blood-brain barrier, regulate blood flow, and contribute to brain repair processes.

Oligodendrocytes

Glial cells in the CNS responsible for forming myelin sheaths around axons.

Schwann Cells

Glial cells in the PNS that myelinate axons and aid in the regeneration of peripheral nerves.

Microglia

The immune cells of the brain that protect against pathogens and clear debris.

Central Nervous System (CNS)

The part of the nervous system that consists of the brain and spinal cord.

Nerve

A bundle of axons enclosed in a protective sheath, transmitting signals between the CNS and various body parts.

Somatic Nervous System

The division of the peripheral nervous system that connects the CNS to skeletal muscles.

Autonomic Nervous System

The part of the PNS that regulates involuntary bodily functions, consisting of sympathetic and parasympathetic divisions.

Sympathetic Division

Part of the autonomic nervous system that prepares the body for 'fight or flight' responses.

Parasympathetic Division

Part of the autonomic nervous system that prepares the body for 'rest and digest' functions.

Gray Matter

Part of the nervous system that contains neuronal cell bodies and is primarily involved in processing information.

White Matter

Part of the nervous system that contains myelinated axons, facilitating communication between different regions.

Corpus Callosum

A large band of neural fibers connecting the left and right hemispheres of the brain.

Cerebrospinal Fluid (CSF)

Fluid that cushions the brain, providing nutrients and removing waste.

Hydrocephalus

A condition characterized by an accumulation of cerebrospinal fluid within the brain's ventricles, leading to increased intracranial pressure.

Blood-Brain Barrier

A selective barrier that protects the brain from harmful substances while allowing nutrients to pass through.

Stroke

A disruption of blood flow to part of the brain, resulting in damage to brain tissue.

Ischemic Stroke

A type of stroke that occurs when blood flow to the brain is obstructed, typically by a blood clot.

Hemorrhagic Stroke

A type of stroke that occurs when a blood vessel in the brain ruptures.

Transient Ischemic Attack (TIA)

A temporary decrease in blood supply to part of the brain, leading to brief stroke-like symptoms.

Five Warning Signs of Stroke

Sudden numbness or weakness on one side, confusion, trouble seeing, difficulty walking or coordination, severe headache.