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CSD 450 Neuroanatomy > Glossary > Flashcards

Flashcards in Glossary Deck (52)
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1
Q

abducens nerve

A

cranial nerve VI, which supplies motor impulses to abduct the eye

2
Q

abduction

A

movement of a body part away from the midline

3
Q

absolute refractory period

A

the short period of membrane unresponsiveness during the passage of an action potential; another action potential cannot be generated during this time.

4
Q

acceleration-deceleration injury

A

type of injury in which the head is accelerated and then suddenly stopped (e.g., motor vehicle accident)

5
Q

acquired childhood aphasia

A

language disorder in which cerebral insult halts or disturbs normal language development in a child.

6
Q

action potential (AP)

A

buildup of electrical current in the neuron.

7
Q

action tremor

A

rhythmic, oscillatory, involuntary movement affecting the outstretched upper limbs as well as other parts of the body and the voice. Also known as essential tremor, heredofamilial tremor.

8
Q

adduction

A

movement of a body part toward midline.

9
Q

adequate stimulus

A

a mechanical, thermal, electrical, or chemical stimulus strong enough to change the cell membrane’s potential.

10
Q

adiadochokinesia

A

inability to perform rapid, alternating muscle movements

11
Q

afferent

A

traveling toward a center

12
Q

agnosia

A

lack of sensory recognition as the result of a lesion in the sensory association areas or association pathways of the brain.

13
Q

agraphia

A

acquired disorder of writing caused by brain injury.

14
Q

akinesia

A

absence or lack of movements

15
Q

alexia

A

acquired disturbance of reading caused by brain injury.

16
Q

alexia with agraphia

A

classic neurological syndrome of reading disorder in which damage has occurred to the angular gyrus and the surrounding areas.

17
Q

alexia without agraphia

A

classic neurologic syndrome of reading disorder, usually caused by a left posterior cerebral artery occlusion in a right-handed person; the resulting infarct produces lesions in the splenium of the corpus callosum and the left occipital lobe.

18
Q

allocortex

A

the older, original part of the cerebral cortex.

19
Q

alpha motor neurons

A

neurons allowing contraction of extrafusal fibers and that have their final common path in cranial and spinal nerves.

20
Q

Alzheimer’s disease

A

the most common type of dementia. Its most striking feature is progressive deterioration of cognitive functions; language disturbance is a major symptom.

21
Q

amyloid plaques

A

axonal endings associated with pathologic deposits of extracellular beta-amyloid. Found in the brain of patients with dementia of the Alzheimer’s type.

22
Q

amyotrophic lateral sclerosis (ALS)

A

a progressive, fatal motor neuron disease usually involving both the upper and lower motor neuron pathways. Also known as Lou Ghrig’s disease.

23
Q

analgesia

A

loss of the sensation of pain.

24
Q

anastomosis

A

a connection between two vessels; an opening created by surgery, trauma, or pathologic condition between two spaces of organs that are normally separate.

25
Q

anencephaly

A

absence of the cranial vault at birth with the cerebral hemispheres completely absent or reduced to small masses attached to the base of the skull.

26
Q

anesthesia:

A

loss of feeling or sensation.

27
Q

aneurysm:

A

a sac formed by the dilation of the wall of an artery, a vein or the heart.

28
Q

angular gyrus

A

convolution in the left parietal lobe that is critical for language processing.

29
Q

anion

A

an ion carrying a negative charge as a result of a surplus of electrons.

30
Q

anistrophy

A

the property of being directionally dependent as opposed to isotropic with means identical properties in all directions.

31
Q

anomia

A

loss of the power to name objects or recognize and recall their names.

32
Q

anomic aphasia

A

an acquired disorder of language caused by brain damage in which the primary difficulty is with word retrieval.

33
Q

anoxia

A

condition marked by the absence of oxygen supply to organs or tissue.

34
Q

anterior horn cell

A

cell in the ventral portion in an H-shaped body of gray matter in the spinal cord associated with efferent pathways

35
Q

anterior spinothalamic tract

A

the uncrossed fibers of the spinothalamic tract, which carry sensations of light or crude touch.

36
Q

anterograde

A

transport of axons from the cell body toward the axon terminal.

37
Q

aphasia

A

acquired disorder of language cause by brain damage; may affect comprehension or expression of language in any modality (spoken, written, or gestural language).

38
Q

aphasic alexia

A

a disorder of reading caused by brain damage; the reading disorder is part of the overall aphasia syndrome (for example, the reading disorder associated with Wernicke’s aphasia)

39
Q

aphemia

A

an obsolete term for loss of the power of speech.

40
Q

apraxia

A

a disorder of learned movement distinct from paralysis, weakness and incoordination; results in a disturbance of motor planning.

41
Q

apraxia of speech (AOS)

A

disorder of programming the muscles of articulation in the absence of paralysis, weakness, and incoordinaiton.

42
Q

aprosodia

A

abnormal prosody (stress and intonation pattern in speech), usually resulting from damage to the non-dominant hemisphere.

43
Q

aqueduct of Sylvius

A

small tube or outlet in the midbrain connective the third and fourth ventricles.

44
Q

arachnoid mater

A

a thing membranous covering (meninges) of the brain and spinal cord that lies between the dura mater and the pia mater.

45
Q

arcuate fasciculus

A

long subcortical association tract connecting posterior and anterior speech-language areas in the cerebrum.

46
Q

areflexia

A

lacking normal reflexive response to an adequate stimulus.

47
Q

arteriosclerosis

A

a chronic disease characterized by abnormal thickening and hardening of the arterial walls, with resulting loss of elasticity.

48
Q

arteriovenous malformation (AVM)

A

congenital morphologic defect resulting in an abnormal cluster of arteries directly connecting to veins; often enlarges over time and is at risk of rupture.

49
Q

articulatory undershoot

A

speech production error in which the active articulatory structure (often the tongue) does not reach its target completely. Often a feature of the articulation of persons with hypokinetic dysarthria.

50
Q

association fiber tracts

A

the fiber bundles that form connections between and within the association areas of the brain.

51
Q

astereognosis

A

loss of the ability to recognize objects through touch along; caused by brain damage.

52
Q

asymmetrical tonic neck reflex (ATNR)

A

a reflex, normal in the newborn, that consists of extension of the arm and sometimes of the leg on the side to which the head is forcibly turned, with flexion of the contralateral limbs. Considered abnormal if found beyond the 8th or 9th. month of age in a term infant.