Neuro-anatomical and Neurological terms Latter A

Action potential the generation of a N impulse through stimulation and depolarizing of the N cell membrane
Acusis hearing
Adiadochokinesia inability to rapidly perform rapidly alternating movements
Afferent incoming - as with sensory fibres see Sensory
Agnosia w/o knowledge inability to recognize sensory stimuli (auditory, tactile, visual)
Agraphia w/o writing - inability to write coherently – due to a cerebral lesion
Ala cinerea ashen hued wing - triangular region on the floor of the 4th Ven – one of the Vagal nuclei
Alexia w/o words - inability to grasp the meaning of words
Allocortex the older cerebral cortex = archicortex + paleocortex
Alveus trough – thin WM layer covering the ventricular surface of the Hp
Amacrine long - the N cell type with long fibrous processes in the retina
Ammon’s horn Ammonis = Egyption god with a ram’s head used for the Hp which sagittally has a curl like a ram’s horn
Amygdala almond - almond shaped body in the Temporal lobe involved in memory & emotion
Anasthesia w/o feeling - loss of sensation
Angular gyrus part of the Temporal lobe involved in language processing, letter shape and word recognition, connects occipital cortex with Wernicke’s area
Anopsia w/o sight - defect of vision
Ansa - loop - a loop like structure eg Ansa Cervicalis
Ant. Cingulate gyrus part of the limbic system - assoc. with cognitive processing of pain perception and emotional response (see cingulum)
Antidromic N impulse running up the axon or down the dendrite in the opposite direction
Aperture an opening or space b/n bones or w/n a bone.
Aphasia w/o speech - loss of speech or comprehension of the written and spoken word
Apraxia w/o being able to do - inability to move purposefully w/o paralysis
Arachnoid spidery – weblike eg AM
Archeocortex AS Archiocortex part of the 3 layered Allocortex in the
Limbic system – mainly in the Hp and Dentate gyrus
Archicerebellum AS Archeocerebellum old part of the little brain – to do with balance
Area postrema caudal area on the floor of the 4th Ven
Articulation joint, which is a point of contact b/n 2 bones / relating to a joint. - hence articular branches of a N supply the joint described.
Association fibres those N fibres which connect cortical areas of the brain ipsilaterally (as opposed to commissural fibres)
Astereognosis w/o solid shape - inability to recognise basic shapes by feeling them
Astrocytes star - one of the supportive cell types in the CNS (see Glia)
Asynergy w/o work - disturbance in the muscle contraction sequence in doing a coordinated act
Ataxia w/o order inability to contract muscles in order andhence weakness in contraction
Athetosis w/o position inability to keep fingers or toes in a still position continually writhing of the extremities – due to degeneration in the CC and Corpus Striatum
Autonomic automatic motor innervation of the viscera
Axial axis - refers to the head and trunk (vertebrae, ribs andsternum) of the body.
Axolemma plasma membrane of the axon
Axon N process carrying material away from the cell body to the target organ, each N has only one axon
Axon collaterals branches of the axon
Axon hillock part of the N where the axon rises and has no Nissl bodies
Axoplasm cytoplasm of the axon