CNS and Sensory Organs Review

Flashcards covering vocabulary, definitions, and specific anatomical facts regarding the Central Nervous System and sensory organs based on Medical University-Varna notes.

Hippocampus (Location)

Located in close proximity to the temporal horn of the lateral ventricle.

N. opticus (Coverings)

The coverings are the pia, arachnoidea, et dura matter.

Fibrae arcuatae internae

Structure formed by the decussation of axons from nucleus gracilis et cuneatus.

A. cerebri anterior (Cortex Supply)

Supplies the part of the primary motor and sensory cortex representing the lower body.

Lamina of Rexed

An anatomical structure that does NOT belong to the white matter.

Tractus spinothalamicus lateralis

Transmits "fast pain" and carries sensory information for pain and temperature from the contralateral side of the body.

Nucleus tractus solitarii (Second Neuron)

Location of the body of the second neuron of the vagal interoceptive system and receives taste information from the tongue.

Genu of capsula interna

The structure formed by fibers of the tractus corticonuclearis.

Central sympathetic nuclei

Found in the thoracic and lumbar levels of the spinal cord.

Glaucoma

An eye disease caused by increased intraocular pressure which collapses the blood capillaries that perfuse the retina so part of it dies.

Tentorium cerebelli

Separates the cerebellum from the cerebrum.

Tractus spinocerebellaris (Anterior et Posterior)

Both tracts carry information from the lower extremity.

Plexus choroideus

The structure that produces Liquor cerebrospinalis (CSF).

Circumventricular organs

The group of organs that have a permeable blood-brain barrier.

Sound Wave Conduction (Air to Inner Ear)

Conducted by the processes of resonance, leverage, and amplification.

Cornea (Refraction)

The site where the greatest refraction occurs as light passes from air into the cornea; it is the chief refractive element of the eye.

Nucleus mediodorsalis

A nucleus that is NOT part of the Nuclei ventrales thalami.

V. ophthalmica superior (Drainage)

Drains into the sinus cavernosus.

Nucleus suprachiasmaticus

The termination site of tractus retinohypothalamicus that regulates melatonin secretion and circadian rhythms.

Fasciculus longitudinalis medialis

Connects vestibular nuclei with cranial nuclei for eye movement, mediating vestibulo-ocular reflexes.

Superficial Mechanoreception (Second Neuron)

The cell body of the second neuron is located in the nucleus gracilis et cuneatus.

Insula (Functional System)

Participates in the taste system (gustatory system).

Colliculus inferior

The principal midbrain nucleus and relay station of the auditory pathway; also acts as an auditory reflex center.

Retinohypothalamic pathway

Visual pathway responsible for the regulation of the circadian rhythm.

Foramen interventriculare Monro

Connects the lateral ventricle with the third ventricle.

Apertura mediana Magendie

A non-paired exit of the fourth ventricle.

Cerebrospinal fluid (Total Volume)

The total volume in humans is around $100-150\,ml$.

Nucleus caudatus

A basal ganglion structure that participates in the formation of the lateral wall of the lateral ventricle.

Tractus vestibulospinalis medialis

Adjusts head posture for maintaining equilibrium and balance.

Purkinje cells

Cerebellar cortex cells that project to the deep cerebellar nuclei, are innervated by climbing fibers, and are inhibited by granule cells.

Common tendineous ring (Muscle Origins)

Origin site for the lateral, inferior, medial, and superior rectus muscles (does NOT include inferior oblique m.).

Lacrimal gland (Innervation)

Receives parasympathetic innervation from the pterygopalatine ganglion.

Corpus geniculatum laterale

The thalamic structure where tractus opticus terminates, functionally related to vision.

Fasciculus of Goll

Also known as the Fasciculus gracilis.

Fasciculus of Burdach

A bundle of nerves in the spinal cord which primarily transmits information from the arms.

A. cerebri media

Direct continuation of the a. carotis interna.

Aqueductus mesencephali (of Sylvius)

Connects the third ventricle with the fourth ventricle; the substantia grisea centralis is located around it.

Dopamine

The neurotransmitter used by efferent fibers of the substantia nigra pars compacta.

Lamina medullaris interna

Structure that separates the thalamus into three parts: anterior, medial, and lateral.

Nervus trochlearis (Decussation)

A cranial nerve that decussates; its nuclei are NOT located in the pons.

Heschl gyrus

The location of the primary auditory cortex (gyrus temporalis superior).

Semicircular duct

The part of the ear that detects the rotation of the head; contains the crista ampullaris.

Bowman's membrane

Also known as Lamina limitans anterior; it is a thickened basal lamina of the corneal epithelium.

Eyelid (Palpebra)

Contains eccrine and apocrine sweat glands and modified sebaceous glands, but is NOT covered by simple squamous epithelium.

Forceps minor

White matter bundle that connects the two frontal lobes.

Forceps major

White matter fiber bundle which connects the occipital lobes via the splenium of the corpus callosum.

Caudal end of Spinal Cord (Adults)

Usually terminates at the level of vertebrae $L1-L2$.

Trabeculae arachnoideae

Formed between the arachnoidea and the pia mater.

Giant cells of Betz

Found in Neocortical Layer $5$.

Internal capsule

Contains both ascending and descending projection fibers.

Corpora mamillaria

Located at the anterior part of the columna fornicis; part of the hypothalamus and the circuit of Papez.

Brodmann area 4

Corresponds to the primary motor cortex located in the gyrus precentralis of the frontal lobe.

Brodmann area 3

Corresponds to the primary somatosensory cortex located in the gyrus postcentralis of the parietal lobe.

Extrapyramidal system (Function)

Part of the motor system network causing involuntary actions, postural control, and complex movements.

Rathke's pouch

An embryological mouth evagination that gives rise to the adenohypophysis.

Fasciculus cuneatus

Transmits conscious proprioception from the upper extremity to the cerebral cortex.

Tractus cuneocerebellaris

Transmits unconscious proprioception from the upper extremity to the cerebellum.

Decussatio pyramidum

Located at the border between the spinal cord and the medulla oblongata; site where fibers of tractus corticospinalis lateralis cross.

Spinal Cord (Segments)

The human spinal cord has $31$ segments.

Circuit of Papez

Represents the neuroanatomical basis of memory formation.