| |
Abstract:
Following unilateral brain damage, a number of patients show
neglect - a failure to notice or respond to information
contralateral to the lesion. However, this contralesional
information is still processed to some extent. A number of studies
have shown that neglected information may affect performance even
though it is not acknowledged by the patient. For example, in a
task requiring the patient to name the color of a color patch,
color names led to Stroop interference whether it was in the
ipsilesional or contralesional field. This occurred despite the
fact that the patient denied the existence of a word in the
contralesional field. We extended these findings by asking whether
all information in the contralesional field will interfere, or only
that which is relevant to the present task. We used local-global
letters in the ipsilesional field and required the patient to
respond to either the local letters or the overall (global) shape.
When naming the global letter, the presence of a competing global
letter in the contralesional field led to interference, while local
letters did not. In contrast, when naming the local letters only
the presence of competing local letters in the contralesional field
caused interference. These results suggest that the effects of
contralesional information may depend on whether it is task
relevant.
|
