acoustic neuroma
- a tumour of the Schwann cell elements of the auditory nerve.
anesthesia
- absence of sensation.
aneurysm
- a focal ballooning out of a segment of blood vessel wall.
Babinski reflex
- an abnormal reflex in which the great toe moves upward and the toes fan upon stroking the lateral plantar surface of the foot. It generally signifies an upper motor neuron lesion.
basal ganglia
- caudate nucleus, lentiform nucleus (= putamen plus globus pallidus), claustrum and amygdala.
bilateral
- both sides of the body.
bitemporal hemianopia
- loss of the temporal (lateral) visual field in each eye.
brachial artery
- the major artery to the upper extremity arising from the subclavian artery.
Brodmann's areas
- a classification of areas of the cerebral cortex according to assigned numbers
calcarine fissure
- the horizontal fissure on the medial aspect of the occipital lobe. It separates the projection from the superior retinae (above) and the inferior retinae (below).
cauda equina
- the bundle of nerve roots extending caudally from the caudal end of the spinal cord.
cerebral cortex
- the narrow zone of the grey matter that lies at the surface of the cerebrum. The grey matter lies external to the white matter in the cerebrum. The reverse is true for the spinal cord.
circumlocution
- the use of many words to express what might be stated by few or one.
coma
- depressed consciousness to the degree of unresponsiveness to noxious stimuli.
conductive hearing loss
- hearing deficit resulting from a mechanical defect in the transmission of sound information between the external ear and the neuronal sensory apparatus (as opposed to neuronal hearing loss).
conjugate gaze
- symmetrical movements of the eyes in a given direction.
contralateral
- the opposite side of the body.
converge
- to move the eyes toward one another.
corticobulbar tract
- the motor pathway between the motor area of the cerebral cortex and the brain stem nuclei.
deja vu phenomenon
- the feeling of having previously experienced a current event.
diencephalon
- thalamus, hypothalamus, epithalamus, plus subthalamus.
dermatome
- the area of skin supplied by one nerve root.
dilation
- expansion.
fasciculations
- coarse muscle twitching seen with peripheral motor nerve injury.
fibrillations
- fine, rarely visible, twitching of single muscle fibres, seen with peripheral motor nerve injury.
flaccid paralysis
- paralysis in which the affected muscles are limp, with little resistance to passive movement.
hemiplegia
- paralysis of the extremities on one side of the body.
homonymous hemianopia
- loss of half of the visual field in each eye for a given side of the environment.
homuculus
- the upside-down representation of the human body on the cerebral cortex.
Horner's syndrome
- pupillary constriction, slight ptosis, and decreased sweating resulting from interruption of the sympathetic pathways to the eye.
hyperpyrexia
- elevation of body temperature.
hyperreflexia
- overactive reflexes.
hyporeflexia
- underactive reflexes.
infarction
- a region of tissue death, resulting from obstruction of the local circulation.
intercostal arteries
- the arteries that run between the ribs. These give contributory branches to the spinal cord.
intermediolateral columns
- the autonomic zone of spinal cord grey matter.
interpalpebral fissure
- the space between the upper and lower eyelids.
ipsilateral
- the same side of the body.
lesion
- injury.
lethargy
- drowsiness.
medially
- toward the midline.
meninges
- the outer lining of the central nervous system (pia, arachnoid, and dura).
meningitis
- inflammation of meninges.
mesencephalic nucleas of 5
- the rostralmost part of the sensory nucleus of CN5.
miosis
- constriction of the pupil.
nasolabial fold
- the skin crease extending from the nose to a point lateral to the corner of the mouth.
neologism
- the use of a new word or an old word in a new sense.
neuron
- nerve cell.
neuronal hearing loss
- hearing deficit resulting from damage to CN8.
obtundation, stupor
- degrees of depressed consciousness between lethargy and coma.
olfaction
- the sense of smell.
olive
- the inferior olivary nucleus in the medulla.
ossicles
- the small ear bones that transmit sound.
paresis
- partial weakness, short of paralysis (which is total).
posterior columns
- the fasciculus gracilis plus fasciculus cuneatus.
pretectum
- the area just deep to the superficial regions of the superior colliculus.
proprioception
- the ability to sense the position of the limbs and their movements, with the eyes closed.
ptosis
- drooping of the eyelid.
radicular pain
- pain along the distribution of a nerve root or primary nerve trunk.
reflex
- an involuntary motion resulting from a stimulus (eg. biceps jerk in response to percussion of the biceps tendon).
retina
- the light-sensitve neural membrane within the eye.
retrograde
- in reverse direction.
sagittal
- in a plane parallel to that which divides an animal into right and left halves.
spastic paralysis
- paralysis with a coinciding steady and prolonged involuntary contraction of the muscles affected.
stereognosis
- the ability to recognize objects by touching and handling them with the eyes closed.
stroke
- a prolonged or permanent loss of function in a brain area, resulting from interruption of the blood supply.
tympanic membrane
- the vibratory membrane separating the external and middle ear.
uncus
- a portion of the temporal lobe concerned with the sense of smell. Epileptic seizures in this area are characterized by unpleasant smells. The uncus lies close to CN3 and may press upon and injure it following a subdural hemorrhage that forces the uncus to herniate against the brain stem.
unilateral
- on one side.
vestibular apparatus
- the balance-sensing mechanism in the inner ear.
visual field
- the portion of the environment that the eye(s) sees on fixed forward gaze.