تقویت توانایی جستجو بصری افراد مبتلا به معلولیت ذهنی

This study aimed to evaluate the effects of cueing in visual search paradigm for people with and without intellectual disabilities (ID). A total of 36 subjects (18 persons with ID and 18 persons with normal intelligence) were recruited using convenient sampling method. A series of experiments were conducted to compare guided cue strategies using either motion contrast or additional cue to basic search task. Repeated measure ANOVA and post hoc multiple comparison tests were used to compare each cue strategy. Results showed that the use of guided strategies was able to capture focal attention in an autonomic manner in the ID group (Pillai's Trace = 5.99, p < 0.0001). Both guided cue and guided motion search tasks demonstrated functionally similar effects that confirmed the non-specific character of salience. These findings suggested that the visual search efficiency of people with ID was greatly improved if the target was made salient using cueing effect when the complexity of the display increased (i.e. set size increased). This study could have an important implication for the design of the visual searching format of any computerized programs developed for people with ID in learning new tasks.

During the past decade, significant theoretical frameworks and empirical studies have been established for the study of human visual search behaviors. One of the most important research areas is the extent to which visual attention can enhance the speed and accuracy with which the target is detected and analyzed (Baldassi & Burr, 2000). The ability to focus attention on relevant features in visual search while limiting attention to irrelevant elements is important in most educational tasks, especially among people with intellectual disabilities (ID), who have been known to be easily distractible (Conners, Caruso, & Detterman, 1986). Several theories have been proposed regarding the nature of the processes involved in feature and conjunction search tasks. Treisman and Gormican (1988) have described two distinct stages of visual processing: (a) pre-attentive stage (i.e. parallel search) which involved distinctions between disparate features on a particular dimension and (b) attentive stage (i.e. serial search) which was a subsequent serial-processing stage that allowed for fine discriminations among the stimuli presented. The assumption of parallel search was that all stimuli were assumed to be processed simultaneously because highly disparate features could be identified rapidly and independently of the number of elements in the array (set size); whereas if the target was not identifiable immediately, e.g. less disparate features, a sequential shift of focal attention across a scene in serial search of the array was required. The hallmark of this theory was that the perceptual analysis of complex visual objects depended on focal attention, and could only occur for one object at a time. It is believed that when target–non-target similarity was high, increasing heterogeneity in the non-target stimuli would result in decreased search efficiency and vice versa.