Chapter 14 and 15 Flashcards

Somatic Nervous System

The system that communicates with our skeletal muscles to allow for body movements in response to information from the body.

Afferent Neurons

Neurons that take sensory information to the brain and spinal cord.

Efferent Neurons

Neurons that send motor commands from the central nervous system back out to the body's periphery.

Primary Somatosensory Area

An area in the parietal lobe where sensory information is perceived.

Interneurons

Neurons that allow for the processing of information within the central nervous system, positioned between sensory and motor neurons.

Myelinated Fibers

A fibers that communicate quickly due to their larger size and presence of myelin.

Unmyelinated Fibers

C fibers that are slower due to lack of myelin.

Transduction

The process of converting a stimulus into an action potential.

Receptive Field

The area of the body that is monitored by a single receptor; smaller fields allow for better localization of stimuli.

Sensation vs. Perception

Sensation is the arrival of information at the central nervous system; perception is the awareness of that information.

General Senses

Senses including temperature, pain, touch, and pressure.

Special Senses

Specific senses including sight, hearing, taste, smell, and balance.

Tonic Receptors

Receptors that are always active and show little adaptation, such as pain receptors.

Phasic Receptors

Receptors that are normally inactive but activate in response to a stimulus, quickly adapting to changes.

Baroreceptors

Receptors that monitor pressure changes in organs, such as the intestines and blood vessels.

Proprioceptors

Receptors that provide information about body position and movement.

Nociceptors

Receptors that detect pain stimuli.

Mechanoreceptors

Receptors that respond to physical changes in the environment, such as pressure or distortion.

Chemoreceptors

Receptors that monitor chemical changes in the body, such as pH, CO2, and O2 levels.

Spinothalamic Pathway

A somatic sensory pathway that transmits pain and temperature information to the brain.

Posterior Column Pathway

A somatic sensory pathway for fine touch and proprioception that ascends to the brain.

Spinocerebellar Pathway

A somatic sensory pathway that transmits information about body position to the cerebellum.

Decussation

The crossing over of nerve fibers to the opposite side, typically occurring in the brainstem or spinal cord.

Visceral reflexes

Reflexes that involve internal organs and are controlled by cranial nerves.

Cranial nerve II

The optic nerve, responsible for vision.

Cranial nerve III

The oculomotor nerve, involved in regulating pupillary constriction and eye movement.

Direct light reflex

The constriction of the pupil in response to light being shined into the eye.

Consensual light reflex

The constriction of the pupil of the opposite eye in response to light in one eye.

Cranial nerve V

The trigeminal nerve, responsible for facial sensation and motor functions like chewing.

Cranial nerve VII

The facial nerve, which controls muscles of facial expression.

Efferent pathway

The motor pathway that carries signals away from the CNS to effectors (muscles/organs).

Afferent pathway

The sensory pathway that carries signals toward the CNS from receptors.

Somatic reflexes

Reflex actions involving skeletal muscles, such as the patellar reflex.

Interneurons

Neurons located within the CNS that communicate between sensory and motor neurons.

Dorsal root ganglion

The cluster of sensory neuron cell bodies found in the dorsal root of spinal nerves.

Perception

The conscious awareness of sensory stimuli.

Propioceptors

Sensory receptors that provide information about body position and movement.

Spinothalamic tract

A pathway that carries pain and temperature sensation from the body to the brain.

Corticospinal pathway

The pathway that directs voluntary movement from the brain to the spinal cord.

Homunculus

A visual representation of the body's sensory and motor areas on the cerebral cortex.

Babinski reflex

A reflex action where the big toe extends upward in response to stimulation of the sole of the foot.

Romberg test

A test used to assess proprioception by measuring balance with eyes closed.

Two-point discrimination

The ability to discern that two nearby objects touching the skin are truly two distinct points.

Pyramidal cells

Upper motor neurons located in the primary motor cortex that influence voluntary movement.

Thalamus

The brain's relay station for sensory information before it reaches the cortex.

Cranial nerves are numbered from to based on their position in the brain.

I to XII

The function of cranial nerve one is related to __, which falls under the category of __ sensory.

smell; special

Cranial nerves send sensory and motor commands to __ side of the body as the side of the brain they originate from.

opposite

The __ is the connecting structure between the two cerebral hemispheres.

corpus callosum

The outer layer of the cerebral hemispheres is known as the __.

cerebral cortex

The is the primary area for processing visual information, while the processes auditory information.

occipital lobe; temporal lobe

The __ cortex in the parietal lobe is responsible for perceiving somatic sensations.

primary somatosensory

Basal nuclei are embedded in matter, while the cerebral cortex is made up of matter.

white; gray

The waves are characteristic of a normal resting adult, while waves are seen in awake, alert individuals.

alpha; beta

During a stroke, symptoms may present on the side of the body if the side of the brain is affected.

left; right

The __ gyrus contains the primary motor cortex responsible for voluntary skeletal movements.

precentral

Cranial nerves can have __ functions such as motor, sensory, or both, unlike spinal nerves which operate the same way.

multiple

The __ sulcus separates the frontal lobe from the parietal lobe in the brain.

central

The area interprets sensory input to allow understanding of various stimuli, while the area helps in articulating speech.

Wernicke's; Broca's

The largest part of the brain is called the __.

Cerebrum

The small part of the brain that coordinates fine movements is called the __.

Cerebellum

The folds of the brain are called __.

Gyri

The grooves of the brain are called __.

Sulci.

The outer region of the cerebrum is known as the __.

Cerebral cortex.

The __ separates the two cerebral hemispheres.

Longitudinal fissure.

The three parts of the brain stem in order from the spinal cord are __, __, and __.

Medulla oblongata, Pons, Midbrain.

Another term for the midbrain is __.

Mesencephalon.

The two parts that make up the diencephalon are and .

Thalamus and Hypothalamus.

The thalamus acts as the __ for ascending sensory information before it reaches the cerebral cortex.

Final relay station.

The act of axons crossing over is called and the area where they cross is known as .

Decussation; Commissure.

The gial cell that produces cerebrospinal fluid (CSF) is called __.

Ependymal cell.

The three layers of meninges in order from outermost to innermost are __, __, and __.

Dura, Arachnoid, Pia.

The blood-brain barrier is maintained by a network of __.

Astrocytes.

The hormone released by the pineal gland that helps regulate sleep is called __.

Melatonin.

The __ is the largest part of the brain.

cerebrum

The second largest part of the brain is the __.

cerebellum

The __ producer of cerebrospinal fluid (CSF) is an ependymal cell.

choroid plexus

The three regions of the brainstem are the medulla, pons, and __.

midbrain

A group of cell bodies in the CNS is termed a __.

nucleus

A group of cell bodies in the PNS is termed a __.

ganglion

The __ is the final relay station for ascending sensory information before it reaches the cerebral cortex.

thalamus

The blood-brain barrier is maintained by __ cells.

astrocyte

The __ separates the right and left cerebral hemispheres.

longitudinal fissure

Cerebrospinal fluid circulates through the __ in the spinal cord.

central canal

The __ regulates hormone release and autonomic functions such as heart rate and body temperature.

hypothalamus

A __ is a deeper groove in the brain surface, while a sulcus is a shallower groove.

fissure

The __ connects the hypothalamus to the pituitary gland.

infundibulum

The __ produces myelin in the CNS.

oligodendrocyte

The process by which sensory information is sorted by the thalamus is similar to how a __ sorts mail.

post office

The outer layer of the brain's surface is known as the __ cortex.

cerebral

The __ ventricle is located in the middle of the brain and connects to the fourth ventricle via the cerebral aqueduct.

third