Agnosia And Apraxia Flashcards
agnosia/apraxia
what is it
altered perception occurs, difficulty making sense of information coming in
perception
what is it an ability of
what does it require
- ability to interpret sensory input or to process visual, somesthetic, auditory input
- requires cortical association areas interacting with primary sensory cortex
Cortical Association Areas (4)
- prefrontal cortex
- temporal lobe
- occipital lobe
- parietal lobe
Prefrontal cortex
5 things it does
- goal directed behavior
- understanding outcomes of behavior
- determining goal achievement
- Short Term Memory
- Emotional Responsiveness
Temporal Lobe
5 things it does
- memory processing: make sense of the memory
- auditory association–makes sense of sounds (area 22, superior temporal gyrus)
- Language comprehension–makes sense of spoken language and written language (Wernickes area)
- Visual Task Memory: make sense of visual input
- Visual Recognition: complex patterns
Occipital Lobe (3)
- visual association area : make sense of visual input
- identify visual input (area 18)
- how to use visual input (area 19)
Parietal lobe (4)
makes sense of sensory input
- somatosensory association area: i am holding a key
- interface sensory and motor cortices
- process spatial aspects of environment
- right hemisphere: body image, tactile discrimination
Parieto Temporal Spatial Occipital Junction
what it does
what a lesion will do
overlapping association area, a polymodal sensory area
ability to make multimodal sense of LANGUAGE as simultaneously written and spoken
there is a dense overlapping association cortex that allows us to make sense of association
lesions result in AGNOSIA or APRAXIA
AGNOSIA
- what causes it
- what is it
“lack of knowledge”
- lesion in association cortex causes inability to interpret sensory input
- agnosia is an acquired condition characterized by an inability to recognize stimuli when transduction, transmission, and perception of stimuli are intact
- -lack of perceptual ability to recognize stimuli (ie stereognosia, graphesthesia)
–cannot interpret, perceive or recognize
–occurs in the presence of normal sensation
–can be agnostic for a specific modality (more common: visual, auditory, tactile) or a subcatogory (facial)
–can touch, feel, and describe it, but cannot recognize or make sense of it
Is sensation intact in agnosia
yes
–can touch, feel, and describe it, but cannot recognize or make sense of it
Body Image
- what is it, how is it formed
- is it acquired
- what lobe
- what happens if difficulties here
1) body acquired mental image about the body formed by synthesis of sensory stimuli
2) acquired through memory of previous body position, movements, relationship to objects
3) nondominant parietal lobe
4) difficulties here result in intact movement skills but difficulty performing functional tasks due to inability to recognize the “meaning” of the task
body image issue
how does it affect movement
difficulties here result in intact movement skills but difficulty performing functional tasks due to inability to recognize the “meaning” of the task
Body Image Agnosis (2)
- somatopagnosia: loss of ability to identify body as a whole or recognize relationship of body parts (not mine)
- hemisomatotopagnosia: impaired ability to recognize 1/2 of body –can feel and use it, but do not recognize it (not mine)
somatopagnosia:
loss of ability to identify body as a whole or recognize relationship of body parts (not mine)
hemisomatotopagnosia:
impaired ability to recognize 1/2 of body –can feel and use it, but do not recognize it (not mine)
Unilateral Neglect (2)
- Hemispatial Neglect: a spatial neglect and do not pay attention to that part of the body.
–impaired attention to 1/2 of body
–NOT agnosia
–complete lack of sensation or awareness of 1/2 of body but not a denial, an IGNORAL
–unaware that the hand is hanging off the w/C
do a clock test - Hemisensory Neglect: loss of sensation of hemi side, they can see it, may be able to use it, but do not feel it
Hemispatial Neglect:
what is it
is it agnosia
what test can we do
a spatial neglect and do not pay attention to that part of the body.
- -impaired attention to 1/2 of body
- -complete lack of sensation or awareness of 1/2 of body but not a denial, an IGNORAL
- -unaware that the hand is hanging off the w/C
–NOT agnosia (can be cued to see it and would know it is their own body) [like when on autopilot]
do a clock test
Hemisensory Neglect:
loss of sensation of hemi side, they can see it, may be able to use it, but do not feel it
hononymous hemianopsia
loss of 1/2 of visual feild
cannot see that side
it is a visual feild cut
in L sided hononymous hemianopsia, one can only see the right visual field
injury to R brain will effect L visual feild
side note: tranndelenburg
When standing on the right leg, if the left hip drops, it’s a positive right Trendelenburg sign (the contralateral side drops because the ipsilateral hip abductors do not stabilize the pelvis to prevent the droop).
finger agnosia
inability to recognize one owns finger from those of the examiner
tactile agnosia
what is it
what causes it
how to test
inability to recognize object by touch in the presence of intact cutaneous and proprioceptive hand sensation
- -inability to synthesize tactile and proprioceptive information (texture, size, weight)
- -difficulty with using scissors, putting on gloves, R and L discrimination
caused by lesion in the CONTRALATERAL PARIETAL LOBE
test with graphesthesia or stereognosis
Visual Agnosia
what is it
what makes us suspect it
common characteristic
inability to interpret visual stimuli despite intact visual sensory apparatus
individual can perceive a visual stimuli, describe its specific characteristics, but is not able to “recognize” its function, structure, or purpose
suspect if :
RO visual acuity
EOM
Visual Fields
CIRCUMLOCATION: talk around it, cannot determine it is a pen, can describe it, do not know what it is for, ask if they know what it is and if they can demonstrate a use for it
CIRCUMLOCATION:
in visual agnosia
talk around it, cannot determine it is a pen, can describe it, do not know what it is for, ask if they know what it is and if they can demonstrate a use for it
Visual Object Agnosia
what is it
how to test it
what causes it
inability to name or demonstrate use of a familiar object
test by giving pt familiar object and asking them to demonstrate its use
indicates lesion in the visual association cortex of the occipital lobe
visual spatial agnosia
what is it
examples
what causes it
how is it tested
inability to perceive spatial relationships between objects or between the object and self
- unable to follow familiar paths
- unable to orient objects in space
- impaired ability to judge distance
- poor depth perception
ie sit down and miss chair
make the bed with everything in the wronge place
RIGHT PARIETAL LOBE
Tests: figure ground design extraction test ask person to touch body parts design copying
Prosopagnosia
what is it
what causes it
how is it tested
facial agnosia
inability to recognize familiar faces, either famous people or close relationships
bilateral medial TEMPORAL-OCCIPITAL LOBE
famous people test
How to test visual-spatial agnosia
figure ground
- design extraction test: find design in the design and perceive 2 identical objects in different positions
- separating objects from two identical ones
- ask person to touch body parts ie left shoulder and right eye etc.
- design copying: draw a design and they have to copy it
Apraxia
what is it
what causes it
praxis = movement organization
loss of movement organization
not caused by incoordination, sensory loss, or failure to follow simple commands
in absence of sensory, motor or language problem
PREMOTOR LESION
What is lost in apraxia, what isnt lost in apraxia
praxis = movement organization
loss of movement organization
not caused by incoordination, sensory loss, or failure to follow simple commands
in absence of sensory, motor or language problem
Types of Apraxia (3)
- ideational
- ideomotor
- special apraxia
Ideational Apraxia
- -what is it
- -what can they not do/what is preserved?
- -give an example
- -what causes it
- cannot form the concept of an action
- inability to form a plan or idea for a specific movement
-ability to DESCRIBE ACTION is preserved
see inability to complete a typical multistep command
ie pick up a pen, write name, put paper into envelope
–>spatial and temporal errors (cannot do multistep command)–incorrect sequencing or may not be able to figure out how to put the paper into the envelope
see diffuse bilateral brain damage AD
dominant lobe lesions
movement looks smooth, NOT like cerebellar overshoot
Ideomotor Apraxia
what is it
what can work
what causes it
- inability to follow commands
- spontaneous movement is intact and can do the movement on their own
-gestural commands may do better than spoken commands
DOMINANT PARIETAL LOBE LESION
[we also see movement to command impaired in PD but different cause]
constructural apraxia
what is it
what can work
what causes it
–unable to use visual information to complete a motor task
- inability to draw or construct a simple figure (lego)
- copying may be ok (draw)
- OCCIPITAL LOBE LESION
dressing apraxia
specific form of apraxia with difficulty sequencing motor actions needed for dressing
IMPAIRMENTS BY LOBE Temporal Lobe (4)
1) memory loss [hippocampus]
2) auditory processing
3) language: WERNICKE’s APHASIA
4) visual : UPPER QUADRANTANOPSIA
IMPAIRMENTS BY LOBE Frontal Lobe (6)
1) apathy (lose will)
2) disinhibition (any urge is acted on)
3) preservation (task, ideal movement, speech repeated over and over)
4) loss of executive function (pay attention to disinhibition)
5) BROCA’s APHASIA
6) contralateral hemiplegia
IMPAIRMENTS BY LOBE Parietal Lobe (5)
- mental status: calculation, perceptual/spatial orientation
- apraxias
- neglect
- VISUAL: homonymous hemianopsia
- sensory: hemisensory deficit
IMPAIRMENTS BY LOBE Occipital Lobe (4)
- visuospatial deficits
- central blindness
- visual hallucinations
- Hemianopsia (lose 1/2 of visual field)
Note to self: determine difference in visual in parietal and temporal and occipital
Note to self: determine difference in visual in parietal and temporal and occipital
