Brain Dysfunction Affecting Perception, Attention, or Memory Flashcards
demage to inferotemporal cortext(what pathway)/Ventral
often have no difficulty reaching/interacting for objects, but they have difficulty describing them
-this difficulty is called AGNOSIA
demage to posterior pariental association cortext(where pathway )/Dorsal
have difficulty reaching accurately for objects that they have no problem describing
DF(patient)
had extensive bilateral ventral-stream lesions
df couldn’t distinguished/describe it blocks but she could interact with it
she knew how to interact with it
Goodale and Milner argued
that the key differece between dorsal and ventral is NOT the kind of information they carry (where or what theory) but how the us the information
ex:
Dorsal streem (posterior parental association: direct behavioural interaction with objects(actions)
Ventral streem (inferotemporal cortex): meditate conscious perception of object (perception)
Agnosia
loss of ability to recognize objects,or sounds,or shapes etc.
(with no memory loss)
it can be lack of connection/knowledge/recognition of any sense
types of agnosia:
-visual
-sound
-motion(can’t perceive motion)
-colour
-figure vs ground (like for ground)
-faces
2 types of agnosia
1-apperceptive agnosia
2-Associative agnosia
1- Apperceptive agnosia ?
failure in recognition linked to problems in perceptual processing
individuals with an apperceptive agnosia are not impaired in matching different normal’’ views of objects, only unusual views
and their ability to recognize degraded stimuli
they are often better with local vs global aspect of an object
in severe cases they might find difficult to copy objects or shapes
2-Associative agnosia
Normal representations but unable to use this information to recognize things
'’pure agnosia’’
individuals with an associative agnosia do well on perceptual test,but cannot access names or other information about objects
failures to experience familiarity with a stimulus
when given name of objects,they can often give accurate verbal descriptions
they can draw/copy but they cant name what they drew
Prosopagnosia
is a failure of face recognition
they can describe faces but not recognize them
Ex: blond,brown eyes,short - but fail to recognize that she is marlyn morrow.
affects previous familiar faces(retrograde components) as well as newly experienced faces(anterograde components)
they can recognize people through voice,clothing and hairstyle
prosopagnosis
dont know if it is associative or apperceptive agnosis
and we don’t know if it is only about faces or little/small changes between general things
their bodies(like skin is shown ) to recognize people they already know/loved ones
capgras illusion
that people that they know are not really them. their neurosistem opposite to prospagnosis cant recognize them
it was found that the human ventral temporal lobe was important in?
in the processing of faces as the Fusiform Face Area(FFA)
found that FFA is important for discriminating faces from objects
occipital face area
as being critical for face processing/identifying faces?
prosopometamorphopsi
will see a face and after a couple seconds the face starts to morph
only for faces!!
attention
is supported by a network largerly in the frontal and pariental cortices of the right hemisphere
posterior pariential association cortext
integrates information about the current position of your body parts with information about the position of external objects that you wish to interact with
contralateral neglect
damage of posterior parietal cortex (right)
cant respond to stimuli to the left
they usually have no recognition of having this deficit
common causes
stroke,TBI,alzeimer
symptoms
-deficit in reporting on objects in space that are opposite to the side of the lision
-spetial bias for directing eye movement and actions towards the opposite side of the lision
almost always right-side damage leading to left-side neglect
-
types of neglect
1-viewer-centered= can only interact with the left half of the image/visual world ( Posterior Parential Cortext)
vs(quite rare)
2-can only interact with left helf of each object (Supirior Temporal Gyrus)
if repeted preset the same spot to the left they will start to orient
they are able to identrify an incomplete drawing to their right,if the complete version is first presented to their left
prism goggles
treatment:
-give prism goggles that shif their vison 10 degrees to the left,
mental imagery
treatmen:
time intensive training
ex: image doing something to your left
TMS
treatment
lasts 15 days
low frequencies to the left posterior cortext seems to reduce the symptoms of neglect
