SPACE – Attention: Visuo-Spatial Attention
The SPACE training program was created for patients with hemineglect but it can also be used successfully with patients who have an impairment of the visual field. It improves the visuospatial directing of attention and is intended to train the specific ability to direct attention to stimuli on the contralesional side of the field of vision.
Scene and Task
The client assumes the role of a photographer. His task is to observe various scenes such as a market place, airport, office, children’s playground etc. The camera viewfinder moves towards a particular point in the area under observation. The task is to take a “photo” by pressing the reaction key as soon the viewfinder stops and has “captured” an object. In each scene there is a fixation point in the center towards which the client should direct the position of his head and the direction of his gaze and where he can find the viewfinder if he has lost sight of it.
In everyday life our attention may be focused on a different source from our perceptive organs. Peripheral stimuli lying outside our central field of vision can attract the focus of attention to themselves. They then bring about a change in the direction of gaze or a turning of the head towards an object or event (visuospatial attention). Peripheral cues tend to bring about an automatic (exogenous) spatial shift of attention, while central cues (e.g. an arrow in the fixation point pointing to the left or right) are more likely to produce a cognitively controlled (endogenous) shift of attention, since a particular expectation is generated. Both peripheral and central cues cause a covert shift of attention to the right or left and thus make it easier to detect stimuli in the half of the visual field in which the cues occur or to which they point (valid condition). However, if the cue is in the wrong half or points in the wrong direction (invalid condition), the speed of reaction to the target stimulus is slowed, since attention must first be shifted from the “wrong” focus to the correct spatial position.
There are ten different difficulty levels, each of which displays a different scene of interest on the screen. The level of difficulty is increased by varying the way in which the viewfinder moves (continuous movement, jumping movement, with and without a return to the center) and the complexity of the scene. In addition, at the lower levels of difficulty the task is made easier by an acoustic and visual cue (sound and arrow in the middle of the viewfinder) which indicates the direction of the next movement. At the higher levels of difficulty only irregular cues are given, and the cues may give no indication of direction or even be completely wrong – for example, the arrow in the viewfinder may point to the upper right while the viewfinder jumps to the lower left.
The instructions for the SPACE training program are displayed on only one side of the screen and are therefore easily read by patients with neglect or visual field impairment.
MAIN AREAS OF APPLICATION
ABILITY MEASURMENT IN VTS
GOOD TO KNOW
We recommend the use of monitors with a screen diagonal of at least 19" so that the area of the visual field being trained is as large as possible.