Lecture 9 Flashcards
Achromatopsia
loss of all cone receptors (no colour vision, poor vision in bright light, poor spatial detail), genetic
Congenital analgesia
lack nociceptors and cannot feel pain (often can feel touch and some temp)
Blindsight
ability of cortically blind people to perform visually mediated tasks without conscious awareness
Agnosia
conscious inability to identify sensory stimuli not due to defecits in sensory, verbal, or cognitive abilities
Visual agnosia
inability to recognize objects, their pictorial representations, or to draw/copy them (can describe features but not state what object is)
Visual object agnosia
can see object but is unable to name, demonstrate use, or remember having seen it before. Lesion in L occipital lobe in V2 but more often bilateral.
Object agnosia for drawings
affects recognition of a variety of drawn stimuli, incl realistic representations of simple objects, geometric figures, meaningless forms, incomplete figures, and abstract drawings. People with this condition can recognize real, physical objects. Lesion in V2.
Akinetopsia
cortical motion blindness; can see objects but have trouble determining if it is moving; damage to MT or parietal lobe
Hemifield neglect
can be restricted to vision but also affects other sensory systems (touch); R posterior parietal lobe damage; patient neglects one side
Dorsal simultagnosia
inability to see 2+ things at once, when multiple objects are present only one is perceived (attended object); worse by motion; due to bilateral damage to parietal and occipital areas
Ventral simultagnosia
inability to identify 2+ things at once, multiple objects can be seen but not identified or integrated; impairments in reading and counting, difficulties describing complex images; due to bilateral damage to temporal and occipital areas
Global deficit
variety of neglect; neglect of vis, aud, and somaestheitc/somatosensory stim on the side of the body/space opposite the lesion
Unilateral spatial neglect
usually left side
Dressing apraxia
dress half the body
Paralexia
read half a word
Paragraphia
writes only half a word
Hemiakinesia
poverty of movement of one side of the body
Anosognosia
denial of illness or symptoms; damage in frontal & parietal lobes (as in alzheimer’s, huntington’s, schizophrenia, bipolar)
Astereognosia
the inability to recognize objects from touch (damage to
primary somatosensory cortex); Also called tactile aphasia; Patients can recognize objects via other senses; This is not due to an inability to name the object – they can mime what the object is for
Asomatognosia
the loss of knowledge or sense of one’s own body &
bodily condition. The person neglects part of his or her body; These may be for one (unilateral) or both (bilateral) sides of the body; most common for the left side of the body resulting from right hemispheric lesions; Correlated with visual neglect, but also involves a bodily dissociation
somatoparaphrenia
denial of ownership of the effected limb or hand; substantial right hemisphere lesions that involve both parietal and somatosensory cortex.
Misoplegia
extreme form of somatoparaphrenia - patient has feelings of hate and revulsion towards a body part; related to substantial right hemisphere lesions that involve both parietal and somatosensory cortex.
Touch apraxia
a loss of skilled movement that is not caused by weakness; an inability to move; abnormal tone or posture, intellectual deterioration, poor comprehension or other disorders of
movement such as tremor.
Ideomotor apraxia
patients are unable to copy movements or to make gestures (waving hello); Damage appears to be in left posterior parietal area.
Constructional apraxia
patients are unable to perform activities such as assembling, building, or drawing; May result from injury to either parietal lobe E.g., these patients cannot put together a puzzle.
Auditory agnosias
difficulty distinguishing environmental and non-verbal auditory cues; Also difficulty distinguishing speech from non-speech sounds; Two classes: Semantic associative (lesion to left hemisphere, Wernicke’s area) & Discriminative (right hemisphere)
Semantic associative disorders
loss of meaning from spoken words; Can read, and understand sign language
Discriminative associative disorders
cannot interpret non-speech sounds and relate to their
cause.
Phonagnosia
inability to recognize or distinguish between voices; some cannot distinguish between voices but can recognize and vice versa; Can understand what is said; can identify emotion in voices (via the limbic system); Loss of recognition caused by damage to the parietal regions of the right hemisphere; Voice discrimination is impaired by temporal lobe damage of
either hemisphere; evidence (limited) of congenital phonagnosia but it’s not
well understood.
Amusia
disruption in recognition of music (tones, melodies, or rhythms)
Osmias
Disorders of smell are called
Anosmia
Inability to detect odors
Unilateral Anosmia
can be caused by minor head trauma (permanent) causing damage to the frontal lobe or olfactory cortex; loss is in one nostril and cannot be detected by testing both at the same time.
Congenital anosmia
absence of the sense of smell from birth.
Anosmia
loss of sense of smell; can be an early sign of degenerative diseases such as Parkinson’s disease and Alzheimer’s disease
Hyposmia
Decreased ability to detect odours
Dysosmia
Distorted identification of smell
Phantosmia
Perception of smell without an odor present
Geusias
Disorders of taste; typically caused by damage to the lingual or glossopharyngeal nerve, but can be caused by damage to the chorda tympani; can be caused by MS/Bell’s Palsy
Ageusia
Inability to taste
Hypogeusia
Decreased ability to taste
Dysgeusia
Distorted ability to taste
