Behavioral Neuro (fixed)

Neuroanatomy

The study of the structure and organization of the nervous system.

Localizationism

The theory that specific parts of the brain are responsible for dedicated functions.

Central Nervous System (CNS)

The division of the nervous system consisting of the brain and spinal cord.

Peripheral Nervous System (PNS)

All parts of the nervous system outside of the brain and spinal cord, including somatic and autonomic divisions.

Somatic Nervous System

The branch of the PNS that conveys sensory information to the CNS and conducts motor commands to skeletal muscles.

Autonomic Nervous System

The branch of the PNS that regulates involuntary body processes such as heart rate, digestion, and blood pressure.

Parasympathetic Nervous System

A division of the autonomic nervous system that conserves energy and maintains bodily function during rest.

Sympathetic Nervous System

A division of the autonomic nervous system that mobilizes body resources during stress or emergency ('fight or flight').

Ganglion

A cluster of neuronal cell bodies located in the peripheral nervous system.

Dorsal Root Ganglion

A nodule on the dorsal root of a spinal nerve containing cell bodies of sensory neurons.

Gray Matter

Nervous tissue composed primarily of neuronal cell bodies, dendrites, unmyelinated axons, and glial cells.

White Matter

Nervous tissue composed mainly of myelinated nerve fiber bundles (tracts) that relay signals across long distances.

Central Canal

A fluid-filled channel running through the center of the spinal cord.

Ventricles

Four interconnected fluid-filled cavities within the brain that produce and contain cerebrospinal fluid.

Cerebrospinal Fluid (CSF)

Clear fluid surrounding and cushioning the brain and spinal cord, serving protective, hormonal, and nutritive roles.

Meninges

The three protective membranes (dura mater, arachnoid mater, and pia mater) enclosing the brain and spinal cord.

Dura Mater

The thick, tough, outermost membrane layer of the meninges.

Arachnoid Mater

The web-like middle layer of the meninges surrounding the brain and spinal cord.

Pia Mater

The delicate, innermost layer of the meninges adhering directly to the surface of the brain and spinal cord.

Hypothalamus

A forebrain structure regulating homeostatic functions, endocrine activity via the pituitary gland, and motivated behaviors.

Pituitary Gland

An endocrine gland at the base of the brain controlled by the hypothalamus that secretes major hormones.

Thalamus

A subcortical forebrain region serving as a primary relay and processing center for sensory and motor information.

Basal Ganglia

Subcortical nuclei (caudate nucleus, putamen, globus pallidus) essential for voluntary movement control and habit learning.

Limbic System

A network of interconnected forebrain structures involved in emotion, motivation, and long-term memory formation.

Midbrain (Mesencephalon)

The central section of the brainstem involved in sensory processing, orienting reflexes, and motor control.

Tectum

The roof of the midbrain comprising the superior and inferior colliculi, responsible for visual and auditory orienting.

Medulla

The lowermost portion of the brainstem controlling vital automatic reflexes like breathing, heart rate, and vomiting.

Cranial Nerves

Twelve pairs of nerves originating directly from the brain/brainstem that convey sensory and motor signals for the head and neck.

Cerebellum

A highly folded hindbrain structure critical for motor coordination, posture, balance, and attentional timing.

Pons

A brainstem structure bridging the midbrain and medulla that contains nuclei key for sleep and wakefulness regulation.

Multipolar Neuron

A neuron having three or more processes attached to its cell body: one axon and multiple dendrites.

Bipolar Neuron

A neuron with two distinct processes extending from opposite sides of the soma: one dendrite and one axon.

Unipolar Neuron

A neuron with a single process extending from the cell body that branches into dendritic and axonal signals.

Dendrite

A branching fiber extending from a neuron that receives chemical inputs from other neurons via synaptic receptors.

Soma (Cell Body)

The central part of a neuron containing the nucleus and organelles where protein synthesis and metabolic work occur.

Axon

A thin nerve fiber that conducts electrical impulses away from the cell body toward other cells.

Axon Hillock

The specialized region connecting the soma to the axon where incoming signals are integrated to initiate action potentials.

Myelin Sheath

A fatty lipid coating wrapped around axons to insulate them and speed up electrical signal transmission.

Nodes of Ranvier

Unsheathed gaps along a myelinated axon where action potentials are regenerated via saltatory conduction.

Afferent Axon

An axon that conveys incoming sensory information toward a target structure or the CNS.

Efferent Axon

An axon that carries outgoing motor information away from a structure or the CNS.

Interneuron

A neuron whose dendrites and axon are entirely contained within a single local brain or spinal structure.

Synapse

The specialized junction where a presynaptic terminal communicates with a postsynaptic cell.

Synaptic Cleft

The tiny, fluid-filled space separating presynaptic and postsynaptic membranes at a chemical synapse.

Astrocytes

Star-shaped glial cells that support neurons, regulate local blood flow, maintain the BBB, and participate in synaptic pruning.

Microglia

Resident immune cells of the central nervous system that engulf cellular debris and respond to neural injury.

Oligodendrocytes

Glial cells responsible for forming myelin sheaths around neuron axons within the Central Nervous System.

Schwann Cells

Glial cells responsible for forming myelin sheaths around axons in the Peripheral Nervous System.

Radial Glia

Specialized glia that guide the migration of developing neurons and axon growth during nervous system development.

Blood-Brain Barrier (BBB)

A selective physical barrier formed by endothelial cells and astrocytes that restricts entry of bloodborne substances into the CNS.

Dualism

The philosophical position that the mind/soul and physical body exist independently as different substances.

Monism

The philosophical view that the universe and mind consist of only one fundamental physical substance.

Bell-Magendie Law

The principle that dorsal spinal roots carry exclusively sensory signals while ventral spinal roots carry motor signals.

Phrenology

A discredited 19th-century doctrine asserting that skull surface contours reflect localized underlying brain faculties.

Broca's Area

A left frontal cortex region specialized for speech production and expressive language function.

Neuron Doctrine

The concept that the nervous system is composed of separate, discrete cellular units rather than a continuous network.

Connectionism

The view that cognitive functions and behaviors emerge from networks of interconnected brain regions working together.

Acetylcholine (ACh)

A major neurotransmitter involved in motor muscle activation, memory processing, and parasympathetic activity.

Amygdala

A limbic system structure crucial for processing emotional stimuli, particularly threat detection and fear learning.

Angiography

A neuroimaging technique used to visualize the structure, location, and condition of cerebral blood vessels.

Arborization

The elaborate, tree-like branching pattern displayed by a neuron's dendritic tree.

Caudal

Anatomical term meaning toward the tail or posterior end of the body and brain.

Rostral

Anatomical term meaning toward the head, beak, or anterior end of the body and brain.

Dorsal

Anatomical directional term meaning toward the back or top surface of the brain and body.

Ventral

Anatomical directional term meaning toward the belly or underside of the brain and body.

Cerebral Cortex

The convoluted outer layer of neural tissue covering the cerebrum, responsible for high-level cognition and perception.

Corpus Callosum

A massive tract of myelinated nerve fibers connecting the left and right cerebral hemispheres.

Diffusion Tensor Imaging (DTI)

An MRI variant that tracks the diffusion of water molecules to map white matter fiber pathways in vivo.

Forebrain

The anterior brain division containing the cerebral hemispheres, basal ganglia, limbic system, thalamus, and hypothalamus.

Frontal Lobe

The anterior region of the cerebral cortex involved in executive function, decision-making, planning, and motor control.

Functional MRI (fMRI)

An imaging technique that measures blood-oxygenation changes to detect localized functional neural activity.

Gyrus

A prominent raised ridge or fold on the surface of the cerebral cortex.

Sulcus

A groove or furrow separating adjacent gyri on the surface of the cerebral cortex.

Hippocampus

A medial temporal lobe structure essential for explicit memory consolidation and spatial navigation.

Ipsilateral

Anatomical term referring to structures located on or affecting the same side of the body.

Occipital Lobe

The posterior cortical lobe specialized primarily for processing visual information.

Parietal Lobe

The cortical lobe situated behind the frontal lobe responsible for somatosensory processing and spatial awareness.

Temporal Lobe

The lateral cortical lobe involved in auditory perception, language comprehension, and memory storage.

Substantia Nigra

A midbrain nucleus containing dopaminergic neurons essential for movement control that degenerates in Parkinson's disease.