Neuropsychological Impairments Flashcards
What is Optic Ataxia?
The inability to point to and/or reach for objects that are reportedly seen. (Differs from visual disorientation). People with Optic Ataxia have no problem locating parts of their own bodies.
What is visual disorientation?
When patients are unable to localize single objects and act as if blind.
They have difficulty directing voluntary eye movement towards and object.
Have problems in reaching for or pointing to an object.
Attentional processes also typically impaired.
Brain damage related to visual orientation deficits.
Usually in the dorsal, occipitoparietal projections. The “where” pathways. In gen. bilateral. Rare, and in the most severe form found in Balint’s syndrome.
Diagnosis of visual disorientation?
Applies to patients who beside normal visual acuity is able to lacalize external sounds and tactile stimulation on her own body. (Rules out motor deficits and demonstrate accurate body sensation and body parts)
Assessment of visual disorientation?
Should only be done in patients who have completed an ophthalmological examination.
Test simple localisation. Like a dot on a paper.
Assess depth discrimination. Estimate distance of objects in the natural environment, or two objects on either the same or different horizontal plane. Tactile test, move the patients finger from one object to the other
Test size discrimination.
Optic ataxia have further two conditions to fulfill.
Test spatial scan and single-point localisation using a dot-counting task.
Two condition test for discriminating Optic Ataxia?
First, ask the patient to reach out and grasp an object that she is looking at.
Second, repeat the manoeuvre with a screen placed between the patient’s head and her arm (prevent her from seeing the hand movement)
Optic Ataxia will only fail at the second condition.
Recovery of visual disorientation ?
Has been observed in unilateral right hemisphere spontaneously.
Some improvement have been observed after non-specific training programs.
See p. 223.
What are the two divisions of complex visuospatial processing?
- Topographical disorientation
2. Spatial analysis deficits.
Topographical disorientation.
Characteristically difficulty in finding their way from one location to another (despite basic visual processing).
May have preserved topographical visual recognition and memory = they get lost even though they recognise the area.
The opposite, loss of topographical recognition, yet preserved spatial knowledge = inability to recognise buildings etc, yet accurate accounts of journeys.
Lesions associated with topographical disorientation?
Predominantly right pariétal damage.
Diagnosis of topographical disorientation?
Interview with patient/carer.
Questions relating to:
Does the patient get lost in familiar surroundings?
Is she unable to learn new simple routes?
Was her way-finding good before the illness?
Assessment of topographical disorientation?
Ask the patient questions such as:
How did you get here?
Can you tell me how to get from A to B. (Familiar places)
How do you go from this room to the ward?
Can you describe your home?
Etc
Recovery and rehabilitation of topographical disorientation?
Difficulties locating objects benefit from written lists, contents of cupboard.
Getting lost on familiar routes - photos of prominent environmental cues to use as landmarks.
Written instructions can be useful.
Simple mnemonics combining names and streets and they location can be used to make meaningful associations with daily journeys.
Walking with the patient in familiar surroundings and then asking the patient to return to the starting point. Length and nr of changes in direction are gradually increased. Finally the patient can draw a map.
What is spatial analysis deficits?
Have difficulty in position discrimination and/or line orientation discrimination.
Detection requires fairly elaborate tasks.
What lesions are associated with spatial analysis deficits?
Predominantly right parietal damage.
Diagnosis of spatial analysis deficits?
Based on quantitative results in a series of specially constructed tests.
How do you assess spatial analysis deficits?
There is a number of tests that assess this.
Position Discrimination
Number location
Cube analysis
Discrimination of line orientation
How is recovery and rehabilitation of spatial analysis deficits?
The earlier assesssment may help the prognosis.
Treatment could be attempted using a tactile version of the cube analysis subtext of the line orientation test. Only for patients presenting spatial analysis deficits in the visual modality only.
Treatment using tactile and visual modalities consists different shapes into the correct holes in a board, timed.
Computer-generated virtual environment that can be explored in real time could be used to treat acquired visuospatial deficits.
Patients with musical abilities could benefit from a rehabilitation programme combining increasing levels of difficulty, figures of cubes and musical isomers. (See p 226)
What is deficit of imaginal processes?
Includes two types of deficits.
A visual imagery deficit.
A spatial imagery deficit.
What is visual imagery deficit?
Part of a deficit group of imagery processes.
The conscious reproduction of previously experienced events and object. Their shape, colour, size, etc.
What is the clinical presentation of Visual imagery deficits?
Patients might not realise that they have this deficit.
Loss of visual imagery may be observed together with visual agnostic, or preserved visual recognition. Also frequently with right homonymous hemianopsia. Right hemiplegia and/or language disturbances can also be present.
What brain damage is associated with visual imagery deficit?
Left posterior lesion.
What is hemianopsia?
It is a decrease or blindness in half of the visual field.
It can be either be homonymous. Meaning the same side of the visual field on both eyes is lost.
Heteronymous is the loss on different sides in both eyes. This is further divided into two. Binasal (visual field around the nose) and bitemporal (closest to the temples).
Superior/inferior means the upper half or lower half respectively.
Quadrantanopia. Is decrease in one quarter of the visual field.
What is the diagnosis criteria of visual imagery deficit?
Can only be diagnosed if the capacity to copy models and describe their visual characteristic is preserved.
How do you assess a visual imagery deficit?
Ask patients to draw from memory. Then to copy from canonical models, objects like a cube, flower, etc.
Ask the patient questions in rich visual attributes (what is the name of the bird [insert full visual description]). Questions about function (the bird that flies, is awake all night long, hoots). Patients with no aphasia symptoms, and impaired visual imagery will only fail the first question.
Present the patient with coloured line drawings of canonical views of animals. Ask the patient to indicate whether the tail is the animal is long or short relative to its body. Has three conditions, that differentiates the ability to conjure imagery from incomplete visual items and auditory input. See p. 228.
For test of visual imagery of colour see p. 228.
How is recovery and rehabilitation of visual imagery deficits?
Using non visual information: a series of familiar and less familiar objects to be tactilely explored. Objects surfaces or parts are covered with fabrics of different textures, which are associated with colours. The patients must describe the shape, imagine the colour, imagine the object on a table, in a bag, near the window etc.
Image rehabilitation is crucial for artistic people.
What is spatial imagery deficit?
The ability (or inability) to conjure images of the location or structure of objects in three dimensions.
What are the clinical presentation of spatial imagery deficits?
Not unusual for patients to say that they have more difficulty “working things out”.
What is the typical beak damage associated with spatial imagery deficit?
Left posterior lesions.
What is the diagnosis criteria for spatial imagery deficits?
This is diagnosed it the patient fails tests of mental transformations. Regardless of his or her inability to conjure up visual images.
How do you assess spatial imagery deficits?
Present the patient with a sheet of paper containing capital letters in random order, half of them upside down. Ask the patient to indicate which letters are the right way up.
Ask the patient to imagine a capital letter and to count the corners. This is sensitive enough to indicate whether extended testing is needed.
Give orally a series of letters with or without curves. Ask the patient to imagine them in the upper case form and to indicate whether or not they have curves.
Present a series of drawings of a man holding a black disc sometimes in his right and sometimes in his left hand. The figure should be shown upside down and dark. The front or from behind. Ask to indicate in which hand the manikin is holding the black discs.
How is recovery and rehabilitation in spatial imagery?
A tactile training device using a board with rotated, mad fast letters.
What defines deficits of constructional processes?
Involve the ability to produce properly organised constructions such as drawings and building tasks. To assemble patterns of simple arrangements made up of blocks, tokens, sticks. Involve normal visual and motor systems to execute visuomotor tasks.
Clinicians use the term constructional apraxia for convenience.
What are the clinical presentations of constructional process deficits?
Patients are unable to grasp the way in which component elements relate to the final model to (re-) produced, and then to fit the components together in the correct spatial organisation.
Brain localisation of constructional process deficits?
Either right or left parietal lesions. Right:left ratio is 3:1. More severe in right and bilateral lesioned cases.
Independent of side, significant correlations between damaged neural substrate of Brodmann’s area 18 with constructional ability.
Left lesions result in oversimplification of the model within the context of a relatively preserved spatial relation. Cause is failure in the organisation of actions necessary for construction tasks
Right lesion patients produce overelaborate, often irrelevant fragments showing spatial disorganisation. Cause, failure in the organisation of space.
How do you diagnose deficits in constructional processes?
If the patients inability to perform drawing and construction tasks occur in the context of the following preserved functions:
Visual form perception.
Spatial localization
Ideomotor praxis
Pure constructional apraxia is rare. However there should be a relative preservation of above functions.
Note complex tasks demands attention and therefore deficits in this area can affect test results. Base it then on easier tasks.
