Midterm Terms Flashcards
Voxel
Smallest unit of 3-D data that can be represent in an MRI
Angiography
Imaging method that visualizes circulatory system of the brain by injecting dye into carotid artery and X-ray
Cerebral vascular accident
Strokes
Blood flow to brain suddenly disrupted - due to blockage of blood passage (embolus-buildup of fatty tissues)
Tumours - gliomas, meningiomas, metastatic tumours
G-abnormal reproduction of glial cells
M-originate in meninges, create abnormal pressure on brain
Meta-originate in non cerebral structure, entered bloodstream and carried to brain
Degenerative disorders
Genetic aberrations and environmental agents
Parkinson’s, Alzheimer’s
Infectious/progressive disordere
Caused by viruses
Auditory pathway
Eardrum, hair cells and basilar membrane in cochlea, midbrain (cochlear nucleus and inferior colliculus), medial geniculate nucleus in thalamus, primary auditory cortex
Olfactory pathways
Olfactory epithelium, olfactory bulb, primary olfactory cortex or orbitofrontal cortex (secondary olfactory processing area)
Aperceptive agnosia
Unable to organize visual features to form coherent perception of objects
More apparent in in right-hemisphere damage
Associative agnosia
Failure to access semantic information to perceived object
Left hemisphere
Optic ataxia
Can recognize object but cannot guide their actions to it
Object constancy
Ability to recognize object in countless situations
Repetition suppression effect
Neural response stimulus is faster when it has been recently activated
Gnostic unit
Neurons at can recognize complex objects that has been encountered in the past
Alexia
Ability to read is disrupted
Integrative agnosia
Failure to integrate parts of objects into whole
Fusiform Face Area
An area of brain, gyrus on the ventral surface of temporal lobe, that respond to faces
Effector
A part of body that can move
Alpha motor neurons
Originate in spinal cord and terminate in muscle fibres, cause muscle contraction
Motor pathway
Hammer stretches quadriceps, muscle spindle (stretch receptor), sensory neuron in dorsal root of spinal cord, alpha motor neuron in ventral root contract quadriceps
extrapyramidal tracts
Rubrospinal
Tectospinal
Vestibulospinal
Reticulospinal
Pyramidal tract
Corticospinal tract, direct contralateral connection from the cortex
Hemiplegia
Lesion of motor cortex, loss of voluntary movement in contralateral side of body
Reflexes become hyperactive due to loss of control in motor cortex
Apraxia
Secondary/association motor areas, commonly left hemisphere
Loss of ability to generate skilled or purposeful movement
Paraplegic
Spinal cord, paralysis of lower limbs
Qudriplegic
Spinal cord, paralysis of all limbs
Ideomotor apraxia
Difficulty in executing desired action properly
Ideational apraxia
Loss of knowledge about actions
Parkinson’s
Cell death in substantial nigra
Disorder of posture and locomotion, hypokinesia (reduction of voluntary movement), bradykinesia (slowness in initiating and executing movement)
Huntington’s
Atrophy in striatum of basal ganglia, clumsiness, involuntary movement, balance problems
