NSCI 2101 Exam 2

Thalamus

Thalamus

Region of the brain that relays most senses and motor information to the brain

Thalamic Adhesion

Structure that separates the halves of the thalamus

Specific Nuclei

Nuclei in the thalamus that relay a certain type of somatosensory information to a certain brain area.

Non-Specific Nuclei

Nuclei that create barriers in and around the thalamus

Internal Medullary Lamina

Sheet of axons from the intralaminar thalamic nuclei that separate the regions of the thalamus

Thalamic Reticular Nucleus

Shell of neurons that inhibits communication from the thalamic nuclei to the cerebral cortex

Association Nuclei

Nuclei in the thalamus that relay multiple types of somatosensory information to association areas in the brain

Thalamic Dorsomedial Nucleus

Association area of the thalamus that relays information to the prefrontal cortex

Thalamic Pulvinar Nucleus

Association area of the thalamus that relays information to the parietal

Allocortex

Inner cerebral cortex

Neocortex

Characteristic layered structure of the outer cerebral cortex

Layer I

Outermost layer of the neocortex

Layer II/III

Layer of the neocortex that

Layer IV

Layer of the neocortex that projects to layers II and III

Layer V

Layer of the neocortex that projects to the brainstem

Layer VI

Layer of the neocortex that projects to the thalamus

Primary Motor Cortex

Cortex that controls movement

Primary Sensory Cortex

Cortex receiving information

from specific thalamic relay nuclei

Association Cortex

Region of the cortex that synthesizes and respond to information from multiple different regions of the cerebral cortex

Cerebral Commissures

Tracts that cross the midline of the brain

Corpus Callosum

Commissure between cerebral hemispheres

Anterior Commissure

Commissure between temporal lobes

Hypothalamus

Limbic structure that provides information to the pituitary gland

Pituitary Gland

Structure that controls the glands of the autonomic nervous system

Hippocampus

Limbic structure in the temporal lobes involved in declarative memory

Amygdala

Limbic structure involved in conditioned fear responses

Fornix

Limbic structure that connects the hypothalamus and hippocampus

Basal Ganglia

Nuclei across the midbrain and forebrain with roles in motor function and motivation

Striatum

Basal ganglia in the telencephalon consisting of the caudate nucleus

Internal Capsule

Gray matter between the caudate nucleus and putamen

Globus Pallidus

Basal ganglia in the telencephalon medial to the putamen

Subthalamic Nucleus

Basal ganglia in the diencephalon ventral to the the thalamus

Skeletal Muscle Cranial Nerves

Cranial nerves that exclusively provide nerves to muscles

Extraocular Muscle Nerves

Skeletal muscle cranial nerves that control eye movement

Oculomotor Nerve

Extraocular muscle nerve that controls the inferior rectus

Abducens Nerve

Extraocular muscle nerve that controls the lateral oblique of the eye.

Trochlear Nerve

Extraocular muscle nerve that controls the superior oblique of the eye

Spinal Accessory Nerve

Muscle nerve for the sternocleidomastoid and trapezius

Hypoglossal Nerve

Muscle nerve for the tongue

Special Sense Cranial Nerves

Cranial nerves that exclusively enables the senses of smell, sight, hearing, and balance

Olfactory Nerve

Specific sensory nerve for smell

Olfactory Bulb

Messenger between the olfactory nerve and cortex

Optic Nerve

Specific sensory nerve for sight

Vestibulocochlear Nerve

Specific sensory nerve for hearing and balance

Trigeminal Nerve

Nerve that controls chewing muscle and interprets general sense

Temporalis

Upper chewing muscle

Masseter

Lower chewing muscle

Mixed Cranial Nerves

Cranial nerves that provide neurons to skeletal muscles and interpret general sensation and taste

Facial Nerve

Nerve that controls facial muscles and interprets taste in the anterior tongue

Facial Autonomic Ganglia

Ganglia of glands that control tears

Glossopharyngeal Nerve

Nerve that controls the pharynx

Glossopharyngeal Autonomic Ganglia

Ganglia of gland that controls salvation

Vagus Nerve

Nerve that controls throat muscles

Carotid Sinus

Swelling in the internal carotid artery that detects blood pressure

Carotid Body

Tissue in the internal carotid artery that detects blood oxygenation

Aortic Arch

Area of the heart that detects blood pressure and blood oxygenation

Somatosensory System

System that detects general sensation

Afferent Neurons

Neurons that carry sensory information

Efferent Neurons

Neurons that carry motor information

Dorsal Roots

Roots of spinal nerves that contain afferent axons

Ventral Roots

Roots of spinal nerves that contain efferent axons

Somatosensory Primary Afferent Neurons

Neurons that innervate sensing tissue

Sensory Receptors

Specific sensors at the peripheral end of a neuron

Dermatomes

Afferent axons in the spine

Mechanoreceptors

Receptors that detect mechanical force

Touch Receptors

Encapsulated mechanoreceptors distributed throughout the skin

Pacinian Corpuscles

Touch receptors for vibration

Two-Point Discrimination

Process of sensing multiple objects on the skin

Proprioceptors

Mechanoreceptors in and around muscles

Muscle Spindles

Organs that sense muscle length and tension

Golgi Tendons

Organs that sense muscle load

Piezo2

Receptor protein found in mechanoreceptor neurons

Knee-Jerk Reflex

Reflex response to a muscle being stretched

Flexor-Withdrawal reflex

Muscular response to pain in the skin

Spinocerebellar Tract

Tract that carries proprioceptive information to the ipsilateral cerebellum

Trigeminothalamic Tract

Tract that carries facial sensation from the trigeminal ganglion to the cerebral cortex

Spinothalamic Tract

Tract that carries pain information from the ventral lateral funiculus of the spine to the contralateral cerebral cortex

Dorsal Column Tract

Tract that carries touch information from root ganglia of the spine to the contralateral cerebral cortex

Medial Lemniscus

Rostral portion of the dorsal column

Fasciculus Cuneatus

Bundle of nerves that carry axons from the upper body to a dorsal column nucleus

Cuneate Nucleus

Lateral dorsal column nucleus

Fasciculus Gracilis

Bundle of nerves that carry axons from the lower body to a dorsal column nucleus

Gracile Nucleus

Medial dorsal column nucleus

Somatotopic Organization

Map of the body within the central nervous system

Sensory Decussation

Point where sensory information crosses the midline

Thalamic Ventral Posterior Lateral Nucleus

Synapse point of the spinothalamic tract and dorsal column

Thalamic Ventral Posterior Medial Nucleus

Synapse point of the trigeminothalamic tract

Primary Sensory Cortex

Postcentral gyrus of the parietal lobe

Limbic Cortex

Area that pain and itch information is projected to for avoidance

Pain Neurons

Thin primary afferent axons

Nociceptors

Pain receptors with free nerve endings and a high threshold potential

Mechanical Nociceptors

Nociceptors triggered by force

Heat Nociceptors

Nociceptors triggered at 45° C

TRPV1

Sensory receptor for heat and capsaicin

Capsaicin

Chemical in peppers that trigger nociceptors

Cold Nociceptors

Nociceptors triggered at 0° C

Polymodal Nociceptors

Nociceptors with multiple types of protein receptors for pain

Acute Pain

Pain that goes away after pain stimulus is removed

Persistent Pain

Pain that occurs during the healing process