Anatomy and Physiology of the Nervous System

CNS

Central Nervous System, consisting of the brain and spinal cord.

PNS

Peripheral Nervous System, includes all neural structures outside the CNS.

Neuroectoderm

The precursor tissue for the nervous system.

Embryology

The study of development of embryos, specifically how tissues develop into organ systems.

Cerebrum

Largest part of the brain responsible for higher brain functions such as thought and action.

Cerebellum

Part of the brain that coordinates muscle movements and maintains posture and balance.

Brain Stem

Connects the brain to the spinal cord and controls basic life functions.

Diencephalon

Part of the brain located between the cerebrum and the brainstem, including the thalamus and hypothalamus.

Thalamus

Acts as the relay station for sensory information to the cerebral cortex.

Hypothalamus

Regulates homeostasis and is involved in emotions and drives.

Basal Nuclei

Cluster of nuclei in the brain involved in the control of movement and coordination.

Cerebral Cortex

The outer layer of the cerebrum, responsible for higher brain functions.

Gyri

Ridges on the surface of the brain.

Sulci

Grooves or fissures on the surface of the brain.

Frontal Lobe

Part of the brain responsible for motor function, problem-solving, and reasoning.

Parietal Lobe

Processes sensory information such as touch and temperature.

Temporal Lobe

Responsible for auditory processing and memory.

Occipital Lobe

Responsible for visual processing.

Brodmann's Areas

52 regions of the cortex classified based on cell structure and function.

Proprioception

The sense of body position.

Kinesthesia

The sense of body movement.

Corpus Callosum

A large bundle of nerve fibers that connects the left and right cerebral hemispheres.

Longitudinal Fissure

Deep groove that separates the two cerebral hemispheres.

White Matter

Myelinated nerve fibers in the CNS, responsible for transmission of signals.

Gray Matter

Unmyelinated nerve cell bodies, dendrites, and synapses in the CNS.

Ventricles

Open spaces in the brain that contain cerebrospinal fluid.

CSF

Cerebrospinal fluid, which cushions and protects the CNS.

Meninges

Three protective membranes covering the brain and spinal cord.

Dura Mater

The tough outermost layer of the meninges.

Arachnoid Mater

The middle layer of the meninges with a web-like structure.

Pia Mater

The delicate innermost layer of the meninges, closely associated with brain tissue.

Spinal Cord

The part of the CNS that is encased within the vertebral column.

Ascending Tracts

Nerve pathways that carry sensory information to the brain.

Descending Tracts

Nerve pathways that carry motor commands from the brain to the body.

Anterior Median Fissure

Deep groove along the anterior midline of the spinal cord.

Posterior Median Sulcus

Shallow groove along the posterior midline of the spinal cord.

Dorsal Root Ganglion

A cluster of sensory nerve cell bodies located outside the spinal cord.

Sensory Neurons

Nerve cells that transmit sensory information to the CNS.

Motor Neurons

Nerve cells that transmit motor commands from the CNS to muscles.

Epineurium

Connective tissue surrounding an entire nerve.

Perineurium

Connective tissue surrounding a fascicle of nerve fibers.

Endoneurium

Connective tissue surrounding individual nerve fibers.

Cranial Nerves

Twelve pairs of nerves that arise directly from the brain.

Spinal Nerves

Nerves that emerge from the spinal cord, combining motor and sensory functions.

Lumbar Plexus

Network of nerves supplying the pelvic region and anterior leg.

Sacral Plexus

Network of nerves supplying the posterior leg and pelvic organs.

Autonomic Nervous System

Part of the PNS that controls involuntary bodily functions.

Sympathetic Nervous System

Part of the autonomic nervous system that prepares the body for stress or emergency.

Parasympathetic Nervous System

Part of the autonomic nervous system that conserves energy and promotes relaxation.

Neural Crest

A group of cells that develop from the neural folds and give rise to various structures.

Neural Tube

The structure formed from fused neural folds that develops into the CNS.

Spina Bifida

A congenital defect in which the neural tube does not close completely.

Neurotransmitter

Chemicals that transmit signals across a synapse.

Acetylcholine

A neurotransmitter involved in muscle movement and memory.

Glutamate

Major excitatory neurotransmitter in the brain.

GABA

Major inhibitory neurotransmitter in the brain.

Homeostasis

The maintenance of stable internal conditions in the body.

Reflex Arc

The neural pathway that mediates a reflex action.

Neurons

Basic building blocks of the nervous system that transmit information.

Glial Cells

Support cells in the nervous system that provide support and protection.

Cerebellar Peduncles

Broad bands of nerve fibers connecting the cerebellum to the brain stem.

Cranial Nerves VII

Facial nerve responsible for controlling facial expressions and taste.

Cranial Nerves VIII

Vestibulocochlear nerve responsible for hearing and balance.

Ependymal Cells

Glial cells that line the ventricles of the brain and produce CSF.

Choroid Plexus

Specialized tissue in the ventricles that produces cerebrospinal fluid.

Thalamus

Part of the diencephalon that is responsible for relaying sensory information.

Hypothalamus

Regulates many autonomic functions and endocrine activities.

Limbic System

A set of brain structures involved in emotion and memory.

Motor Cortex

Region of the cerebral cortex involved in planning and executing voluntary movements.

Sensory Cortex

Region of the cerebral cortex that processes sensory information.

Association Cortex

Regions of the cerebral cortex that integrate sensory and motor functions.

Cognitive Functions

Mental processes that include perception, memory, and reasoning.

Short-Term Memory

Memory that holds information for a limited time.

Long-Term Memory

Memory that retains information over extended periods.

Plexus

Network of nerves or blood vessels.

Cauda Equina

Bundle of spinal nerves that extends beyond the end of the spinal cord.

Peripheral Nerves

Nerves outside the central nervous system.

Neural Pathway

A series of connected neurons that transmit information in the nervous system.

Electrical Synapse

Synapse where signal transmission occurs via gap junctions.

Chemical Synapse

Synapse where communication between neurons occurs via neurotransmitters.

Homeostatic Control

Mechanisms that maintain physiological balance in the body.

Reflexes

Involuntary responses to stimuli.

Neural Processing

The transformation of sensory input into meaningful perceptions.

Sensory Receptors

Specialized cells that detect changes in the environment.

Neural Integration

The process of processing and interpreting sensory information.

Pain Perception

The awareness of pain resulting from nerve impulses.

Somatic Nervous System

Part of the PNS that oversees voluntary control of body movements.

Sympathetic Response

The body's fight or flight response to