RAPID REORIENTATION OF ATTENTION IN CHILDREN WITH AND WITHOUT ATTENTION DEFICITS (COGNITIVE DEVELOPMENT, HYPERACTIVITY, DISORDER)
PEARSON, DEBORAH ANN
Doctor of Philosophy thesis
The ability to reorient attention rapidly in both the auditory and visual modalities was first assessed developmentally and then assessed in children diagnosed as having Attention Deficit Disorder with Hyperactivity (314.01, DSM III). In the first experiment, eight-year old, eleven-year old, and college age subjects listened to dichotically presented lists for prespecified targets. On half of the trials, subjects were signaled to reorient their attention from one ear to the other during the list; on the other half, they remained on the same ear throughout the list. When performance was compared in the switch and no switch conditions, a progressive improvement with age was found in the ability to "switch gears." The ability to reorient attention visually in the same age range was measured in a second experiment. In this experiment, subjects first oriented their attention to the center of a cathode ray tube. Subjects were then cued that a target would shortly appear either to the left or to the right of this central location. Following a variable interval, the target appeared at the cued location. A steady improvement with age was found in the speed of reorientation from the central point to the target area. In a third experiment, auditory reorientation of attention was measured in hyperactive and nonhyperactive children matched for age, sex, and IQ. Using the same task used in the first experiment, it was found that although nonhyperactive children were temporarily disrupted by the switch, they eventually reoriented to the correct ear. In contrast, once the hyperactive children were disrupted by the switch, they never seemed to recover, at least not within the time frame of this experiment. This pattern resembled that of the youngest group in the first experiment, thus lending support to the hypothesis that hyperactive children are developmentally immature. A final experiment measured differences in visual reorientation in hyperactive and nonhyperactive children. Using the paradigm used in the second experiment, no differences were found between the two groups. It was suggested that the attentional abilities of hyperactive children may be highly dependent upon task characteristics.