Biomedical subjects

W La Heij

Publications and source records attributed to W La Heij.

10 recordsLinked to original sources

PubMed1996

Stroop interference and disorders of selective attention.

Fourteen patients with right-hemisphere CVA and 8 patients with a left-hemisphere CVA were examined for selective attention deficits using a variant of the Stroop color-word task: the picture-word interference task. Experiments 1 and 2 first compared the performance of the two patient groups and a control group in three tasks of increasing difficulty: picture-word detection, word reading, and picture naming. The results showed that (a) the two patient groups were significantly slower than the control group, but did not differ from each other, and (b) the difference in mean RT between the two patient groups and the control group did not increase with task difficulty. In Experiment 3, the subjects were required to name pictures while ignoring accompanying distractors: nonletter symbols, unrelated words or semantically related words. In this task, the right hemisphere patients showed a much larger semantic interference effect than both the left hemisphere patients and the control group. It is argued that this finding most probably reflects problems in visual selective attention with the right hemisphere patients.

Aged↗

PubMed1995

Reducing color-color interference by optimizing selection for action.

Color-color interference refers to the finding that the naming of a target color is hampered by the simultaneous presentation of an incongruent distractor color somewhere else in the visual field. This interference effect has been attributed to an imperfect input selection (selection-for-processing). We test an alternative account in which it is assumed that (a) target and distractor are identified in parallel without mutual interference, (b) the identified target color has to be selected to control the naming response (selection-for-action), and (c) this selection process takes more time and is less accurate in the incongruent condition than in the control conditions. Experiment 1 shows that color-color interference obtained when a target color, presented at the point of fixation, is flanked by incongruent colors. In Experiments 2 and 3, the central target position is indicated by an additional exogenous selection cue. The results show that an abrupt-onset cue, presented at the central target position 160 ms after the onset of the target and distractors, reduces the interference effect. This finding is interpreted as supporting evidence for a selection-for-action account of color-color interference.

Adult↗

PubMed1990

Components of Stroop-like interference in word reading.

Previous research has shown that the naming of the picture of, for example, a guitar is substantially delayed when it is accompanied by the name of an object from the same semantic category (e.g., piano) as compared to a nonword control (e.g., xxxxx). La Heij (1988a) has shown that a large part of this Stroop-like interference effect can be attributed to two semantic characteristics of the distractor word: its semantic similarity to the target picture and its semantic relevance in the task at hand. Furthermore, it was argued that the locus of these two interference effects is the process of target-name retrieval. If this is true, semantic interference effects should diminish or disappear when, instead of a picture-naming task, a word-reading task is used. In the present study this prediction is tested. The effects of four distractor characteristics are examined: semantic relatedness, semantic relevance, response set membership and wordness. In contrast to the original picture-naming task only the effect of wordness reached significance. The results of experiments 2 and 3 show that the absence of significant semantic context effects in experiment 1 is not simply due to the fact that a distractor word has less time to affect a word-reading response. The results are taken to support a name-retrieval account of semantic interference in color and picture naming.

Adult↗

PubMed1988