Part of the cerebral cortex that directs movements toward a goal or to perform a task, such as grasping an object; lies posterior to the central sulcus and beneath the parietal bone at the top of the skull.

Sudden appearance of neurological symptoms as a result of severely interrupted blood flow.

The principle that sensory fibers are dorsal and motor fibers are ventral.

The between brain, which integrates sensory and motor information on its way to the cerebral cortex.

Part of the autonomic nervous system; acts in opposition to the sympathetic division—for example, preparing the body to rest and digest by reversing the alarm response or stimulating digestion.

Midbrain area in which nuclei and fiber pathways are mixed, producing a netlike appearance; associated with sleep-wake behavior and behavioral arousal.

A groove in brain matter; most are in the neocortex or cerebellum.

Part of the autonomic nervous system; arouses the body for action, such as mediating the involuntary fight-or-flight response to alarm by increasing heart rate and blood pressure.

Central part of the brain; contains neural circuits for hearing and seeing as well as orienting movements.

Increase in the activity of a neuron or brain area.

Disorder of the basal ganglia characterized by tics, involuntary vocalizations (including curse words and animal sounds), and odd, involuntary movements of the body, especially of the face and head.

Conducting away from a CNS structure.

Three layers of protective tissue—dura mater, arachnoid, and pia mater—that encase the brain and spinal cord.

Diencephalon structure that contains many nuclei associated with temperature regulation, eating, drinking, and sexual behavior.

An individual’s capacity to develop into more than one phenotype.

Evolutionarily the newest part of the brain; coordinates advanced cognitive functions such as thinking, planning, and language; contains the limbic system, basal ganglia, and neocortex.

Body segment corresponding to a segment of the spinal cord.

Most recently evolved outer layer (new bark) of the forebrain, composed of about six layers of gray matter; constructs our reality.

Mesh of neurons embedded in the lining of the gut, running from the esophagus through the colon; controls the gut.

Roof (area above the ventricle) of the midbrain; its functions are sensory processing, particularly visual and auditory, and the production of orienting movements.

Part of the cerebral cortex where visual processing begins; lies at the back of the brain and beneath the occipital bone.

One of four cavities in the brain that contain CSF to cushion the brain; may play a role in maintaining brain metabolism.

The nervous system’s potential for physical or chemical change to adapt to environmental change and to compensate for injury.

Part of the PNS that regulates the functioning of internal organs and glands.

Areas of the nervous system rich in fat-sheathed neural axons that form the connections between brain cells.

Subcortical forebrain nuclei that coordinate voluntary movements of the limbs and body; connected to the thalamus and to the midbrain.

Part of the PNS that includes the cranial and spinal nerves to and from the muscles, joints, and skin, which produce movement, transmit incoming sensory input, and inform the CNS about the position and movement of body parts.

Large collection of axons coursing together outside the CNS.

Degenerative brain disorder related to aging that first appears as progressive memory loss and later develops into generalized dementia.

Band of white matter containing about 200 million nerve fibers that connects the two cerebral hemispheres to provide a route for direct communication between them.

Conducting toward a CNS structure.

Evolutionarily the oldest part of the brain; contains the pons, medulla, reticular formation, and cerebellum, structures that coordinate and control most voluntary and involuntary movements.

A small protrusion or bump formed by the folding of the cerebral cortex.

Part of the cerebral cortex that functions in connection with hearing, language, and musical abilities; lies below the lateral fissure, beneath the temporal bone at the side of the skull.

Map of the neocortex based on the organization, structure, and distribution of the cells.

Disparate forebrain structures lying between the neocortex and the brainstem that form a functional system controlling affective and motivated behaviors and certain forms of memory; includes cingulate cortex, amygdala, and hippocampus, among other structures.

The bones that form the spinal column.

Movement related to sensory inputs, such as turning the head to see the source of a sound.

Decrease in the activity of a neuron or brain area.

Part of the cerebral cortex often generally characterized as performing the brain’s executive functions, such as decision making; lies anterior to the central sulcus and beneath the frontal bone of the skull.

Central structure of the brain, including the hindbrain, midbrain, thalamus, and hypothalamus, that is responsible for most unconscious behavior.

Thin, heavily folded film of nerve tissue composed of neurons that is the outer layer of the forebrain. Also called neocortex.

Clear solution of sodium chloride and other salts that fills the ventricles inside the brain and circulates around the brain and spinal cord beneath the arachnoid layer in the subarachnoid space.

Large collection of axons coursing together in the CNS.

Diencephalon structure through which information from all sensory systems is integrated and projected into the appropriate region of the neocortex.

Areas of the nervous system composed predominantly of cell bodies and capillary blood vessels that either collect and modify information or support this activity.

Floor (area below the ventricle) of the midbrain; a collection of nuclei with movement-related, species-specific, and pain perception functions.

One of a set of 12 nerve pairs that control sensory and motor functions of the head, neck, and internal organs.

A group of cells forming a cluster that can be identified with special stains to form a functional grouping.

Disorder of the motor system correlated with a loss of dopamine from the substantia nigra and characterized by tremors, muscular rigidity, and a reduction in voluntary movement.