Central Nervous System and Autonomic Nervous System Overview (Chapters 12-14)

These flashcards cover essential vocabulary and concepts related to the central nervous system, autonomic nervous system, and special senses to aid in exam preparation.

Falx cerebri

A sickle-shaped fold of dura mater that separates the two cerebral hemispheres.

Longitudinal fissure

A deep groove that divides the brain into left and right hemispheres.

Central sulcus

The groove that separates the frontal lobe from the parietal lobe.

Precentral gyrus

The gyrus located in front of the central sulcus; responsible for motor control.

Postcentral gyrus

The gyrus located behind the central sulcus; responsible for sensory perception.

Gray matter

Regions of the brain and spinal cord primarily made up of neuronal cell bodies.

White matter

Regions of the brain and spinal cord made up of myelinated axons.

Commissural tracts

Connections that allow communication between the two hemispheres of the brain.

Association tracts

Connections that link different regions within the same hemisphere.

Projection tracts

Connections that extend between the cortex and lower brain regions.

Primary sensory cortex

Brain area responsible for processing sensory information from the body.

Primary motor cortex

Brain area responsible for voluntary motor control.

Visual cortex

Region of the occipital lobe that processes visual stimuli.

Auditory cortex

Region of the temporal lobe responsible for processing auditory information.

Broca's center

Area in the frontal lobe associated with language production.

Wernicke's center

Area in the temporal lobe associated with language comprehension.

Choroid plexus

Structure in the brain that produces cerebrospinal fluid (CSF).

Epidural hematoma

A collection of blood in the epidural space, usually due to trauma.

Subdural hematoma

A collection of blood between the dura mater and the brain, often resulting from head injury.

Basal nuclei

Group of subcortical structures involved in the regulation of motor control.

GABA (gamma-aminobutyric acid)

Inhibitory neurotransmitter found in the basal nuclei.

Thalamus

Part of the diencephalon that relays sensory information to the cerebral cortex.

Hypothalamus

Part of the diencephalon responsible for regulating autonomic functions and homeostasis.

Epithalamus

Part of the diencephalon that includes structures such as the pineal gland.

Midbrain

The uppermost part of the brainstem; involved in vision, hearing, and motor control.

Pons

Part of the brainstem that links the medulla oblongata with the thalamus.

Medulla oblongata

Part of the brainstem that controls vital autonomic functions.

Cerebellum

Brain region responsible for coordinating voluntary movements and balance.

Ataxia

A neurological sign consisting of lack of voluntary coordination of muscle movements.

Limbic system

Set of brain structures associated with emotions and memory.

Reticular formation

Network of neurons that regulates states of consciousness and alertness.

Reticular activating system

Part of the reticular formation that regulates arousal and wakefulness.

Filum terminale

A fibrous extension of the pia mater that anchors the spinal cord to the coccyx.

Cauda equina

A bundle of spinal nerves and spinal nerve roots located below the spinal cord.

Dorsal root ganglion

Collection of sensory neuron cell bodies in the dorsal root of a spinal nerve.

Dorsal root

The sensory root of a spinal nerve that carries sensory information to the spinal cord.

Posterior gray horn

Region of the spinal cord that processes incoming sensory information.

Anterior gray horn

Region of the spinal cord that contains motor neuron cell bodies.

Ventral root

The motor root of spinal nerves that carries motor output from the spinal cord.

Spinal tap

Procedure to collect cerebrospinal fluid for diagnostic testing.

Ganglion

A cluster of nerve cell bodies located outside the central nervous system.

Nucleus

A cluster of nerve cell bodies located within the central nervous system.

Sensory pathways

Neural pathways that carry sensory information from the body to the brain.

Direct (pyramidal) motor pathway

Neural pathways that control voluntary movements.

Anterior spinothalamic tract

Sensory pathway that transmits information about crude touch and pressure.

Lateral spinothalamic tract

Sensory pathway that transmits pain and temperature sensations.

Dorsal columns pathway

Sensory pathway that transmits proprioception and fine touch.

Flaccid paralysis

Loss of muscle tone and reflexes due to nerve damage.

Spastic paralysis

Impairment characterized by increased muscle tone and reflexes due to upper motor neuron lesions.

Paraplegia

Loss of motor function in the lower limbs due to spinal cord injury.

Quadriplegia

Loss of motor function in all four limbs due to spinal cord injury.

Poliomyelitis

Viral disease that affects motor neurons, leading to paralysis.

Plexus

Network of intersecting nerves that supplies specific body regions.

Dermatomes

Skin regions innervated by sensory fibers of a single spinal nerve.

Interoceptor

Receptor that responds to internal stimuli.

Exteroceptor

Receptor that responds to external stimuli.

Proprioceptor

Receptor that senses body position and movement.

Meissner corpuscle

Type of mechanoreceptor that detects light touch.

Merkel disc

Type of mechanoreceptor involved in tactile sensation.

Pacinian corpuscle

Type of mechanoreceptor that detects deep pressure and vibration.

Nociceptor

A sensory receptor that responds to potentially harmful stimuli, signaling pain.

Adaptation

The process by which sensory receptors diminish their response to a constant stimulus.

Punctate distribution

The pattern of sensory receptors distributed throughout the skin.

Chemoreceptor

Receptor that responds to chemical stimuli.

Photoreceptor

Receptor that responds to light, primarily found in the retina of the eye.

Mechanoreceptor

Receptor that responds to mechanical pressure or distortion.

Reflex arc

The neural pathway that mediates a reflex action.

Stretch reflex

A reflex that helps maintain muscle tone and posture.

Muscle spindle

Sensory receptors located in muscles that detect changes in muscle length.

Golgi tendon organ

Proprioceptors that sense changes in muscle tension.

Withdraw reflex

A protective reflex that causes withdrawal from a harmful stimulus.

Ipsilateral reflex

Reflex response occurring on the same side as the stimulus.

Bilateral reflex

Reflex response occurring on both sides of the body.

Contralateral reflex

Reflex response occurring on the opposite side from the stimulus.

Autonomic reflex

Reflexes that involve the autonomic nervous system and regulate involuntary functions.

Somatic reflex

Reflexes that involve the somatic nervous system and control voluntary movements.

Pupillary reflex

Reflex that controls the diameter of the pupil in response to light.

Dual innervation

A situation in which an organ is innervated by both sympathetic and parasympathetic fibers.

Sympathetic fibers

Nerve fibers that promote the fight-or-flight response.

Parasympathetic fibers

Nerve fibers that promote the rest-and-digest response.

Preganglionic neuron

Neuron that transmits impulses from the central nervous system to ganglia.

Postganglionic neuron

Neuron that transmits impulses from ganglia to target organs.

Adrenal medullae

Part of the adrenal glands that secretes hormones like adrenaline in response to stress.

Sympathomimetic drugs

Drugs that mimic the effects of the sympathetic nervous system.

Parasympathomimetic drugs

Drugs that mimic the effects of the parasympathetic nervous system.

Sympatholytic drugs

Drugs that inhibit the effects of the sympathetic nervous system.

Parasympatholytic drugs

Drugs that inhibit the effects of the parasympathetic nervous system.

Lacrimal gland

Gland that produces tears, innervated by the parasympathetic system.

Extrinsic eye muscles

Muscles that control eye movement, innervated by cranial nerves.

Choroid

Layer of blood vessels in the eye that supplies nutrients to the retina.

Ciliary body

Structure in the eye that controls lens shape for focusing.

Fovea centralis

Zone of highest visual acuity on the retina, responsible for sharp central vision.

Accommodation

The process by which the eye changes focus from distant to near objects.

Hyperopia

Farsightedness; difficulty focusing on close objects.

Myopia

Nearsightedness; difficulty focusing on distant objects.

Cataract

A clouding of the lens that impairs vision.

Astigmatism

An optical defect causing the image to be blurry due to uneven curvature of the cornea.

Glaucoma

A group of eye conditions that damage the optic nerve, often due to increased intraocular pressure.

Aqueous humor

Fluid in the anterior and posterior chambers of the eye, produced by the ciliary body.

Optic chiasma

X-shaped structure where the optic nerves partially cross.