The acquisition of contextual cueing effects by persons with and without intellectual disability

Top-down, bottom-up, and history-driven processing of multisensory attentional cues in intellectual disability: An experimental study in virtual reality

Models of attention demonstrated the existence of top-down, bottom-up, and history-driven attentional mechanisms, controlled by partially segregated networks of brain areas. However, few studies have examined the specific deficits in those attentional mechanisms in intellectual disability within the same experimental setting. The aim of the current study was to specify the attentional deficits in intellectual disability in top-down, bottom-up, and history-driven processing of multisensory stimuli, and gain insight into effective attentional cues that could be utilized in cognitive training programs for intellectual disability. The performance of adults with mild to moderate intellectual disability (n = 20) was compared with that of typically developing controls (n = 20) in a virtual reality visual search task. The type of a spatial cue that could aid search performance was manipulated to be either endogenous or exogenous in different sensory modalities (visual, auditory, tactile). The results identified that attentional deficits in intellectual disability are overall more pronounced in top-down rather than in bottom-up processing, but with different magnitudes across cue types: The auditory or tactile endogenous cues were much less effective than the visual endogenous cue in the intellectual disability group. Moreover, the history-driven processing in intellectual disability was altered, such that a reversed priming effect was observed for immediate repetitions of the same cue type. These results suggest that the impact of intellectual disability on attentional processing is specific to attentional mechanisms and cue types, which has theoretical as well as practical implications for developing effective cognitive training programs for the target population.

Visual statistical learning in children and adults: evidence from probability cueing

In visual statistical learning (VSL), one can extract and exhibit memory for the statistical regularities of target locations in an incidental manner. The current study examined the development of VSL using the probability cueing paradigm with salient perceptual cues. We also investigated the elicited attention gradient phenomenon in VSL. In a visual search task, the target first appeared more often in one quadrant (i.e., rich) than the other quadrants (i.e., sparse). Then, the participants rotated the screen by 90° and the targets appeared in the four quadrants with equal probabilities. Each quadrant had a unique background color and was, hence, associated with salient perceptual cues. 1st-4th graders and adults participated. All participants showed probability cueing effects to a similar extent. We observed an attention gradient phenomenon, as all participants responded slower to the sparse quadrant that was distant from, rather than the ones that were adjacent to the rich quadrant. In the testing phase, all age groups showed persistent attentional biases based on both egocentric and allocentric perspectives. These findings showed that probability cueing effects may develop early, that perceptual cues can bias attention guidance during VSL for both children and adults, and that VSL can elicit a spaced-based attention gradient phenomenon for children and adults.

Implicit memory of locations and identities: A developmental study

Objects in the environment have both location and identity properties. However, it is unclear how these independent properties are processed and combined in the implicit domain. The current study investigated the development of the implicit memory of object locations and object identities, both independently and combined, and the relation between implicit memory and working memory (WM) for these properties. Three age groups participated: 6- and 7-year-old children, 9- and 10-year-old children, and adults. Children and adults completed a repeated search paradigm. In the learning phase, targets' locations were consistently predicted by both the identities and locations of the distracters. In the test phase, either both remained predictive or just the identities or just the locations of the distracters predicted the location of the target. All groups showed significant implicit learning when both the identities and locations of the distracters remained predictive. When only the locations but not the identities of the distracters were predictive, adults and 9- and 10-year-olds showed significant learning, whereas 6- and 7-year-olds did not. When only the identities but not the locations of the distracters were predictive, none of the groups showed significant learning effects. In evaluating the contributions of either visual or spatial WM to implicit learning and memory, we found that children with smaller visual WM exhibited larger implicit memory effects for object identities than did children with larger visual WM. Taken together, the results indicate that children's ability to differentiate identity and location undergoes development even in the implicit domain.

Media multitasking and implicit learning

Media multitasking refers to the simultaneous use of different forms of media. Previous research comparing heavy media multitaskers and light media multitaskers suggests that heavy media multitaskers have a broader scope of attention. The present study explored whether these differences in attentional scope would lead to a greater degree of implicit learning for heavy media multitaskers. The study also examined whether media multitasking behaviour is associated with differences in visual working memory, and whether visual working memory differentially affects the ability to process contextual information. In addition to comparing extreme groups (heavy and light media multitaskers) the study included analysis of people who media multitask in moderation (intermediate media multitaskers). Ninety-four participants were divided into groups based on responses to the media use questionnaire, and completed the contextual cueing and n-back tasks. Results indicated that the speed at which implicit learning occurred was slower in heavy media multitaskers relative to both light and intermediate media multitaskers. There was no relationship between working memory performance and media multitasking group, and no relationship between working memory and implicit learning. There was also no evidence for superior performance of intermediate media multitaskers. A deficit in implicit learning observed in heavy media multitaskers is consistent with previous literature, which suggests that heavy media multitaskers perform more poorly than light media multitaskers in attentional tasks due to their wider attentional scope.

Investigating implicit statistical learning mechanisms through contextual cueing

Since its inception, the contextual cueing (CC) paradigm has generated considerable interest in various fields of cognitive sciences because it constitutes an elegant approach to understanding how statistical learning (SL) mechanisms can detect contextual regularities during a visual search. In this article we review and discuss five aspects of CC: (i) the implicit nature of learning, (ii) the mechanisms involved in CC, (iii) the mediating factors affecting CC, (iv) the generalization of CC phenomena, and (v) the dissociation between implicit and explicit CC phenomena. The findings suggest that implicit SL is an inherent component of ongoing processing which operates through clustering, associative, and reinforcement processes at various levels of sensory-motor processing, and might result from simple spike-timing-dependent plasticity.

Patterns of differences in wayfinding performance and correlations among abilities between persons with and without Down syndrome and typically developing children

Down syndrome (DS) impacts several brain regions including the hippocampus and surrounding structures that have responsibility for important aspects of navigation and wayfinding. Hence it is reasonable to expect that DS may result in a reduced ability to engage in these skills. Two experiments are reported that evaluated route-learning of youth with DS, youth with intellectual disability (ID) and not DS, and typically developing (TD) children matched on mental age (MA). In both experiments, participants learned routes with eight choice point presented via computer. Several objects were placed along the route that could be used as landmarks. Participants navigated the route once with turn indicators pointing the way and then retraced the route without them. In Experiment 1 we found that the TD children and ID participants performed very similarly. They learned the route in the same number of attempts, committed the same number of errors while learning the route, and recalled approximately the same number of landmarks. The participants with DS performed significantly worse on both measures of navigation (attempts and errors) and also recalled significantly fewer landmarks. In Experiment 2, we attempted to reduce TD and ID vs DS differences by focusing participants’ attention on the landmarks. Half of the participants in each group were instructed to identify the landmarks as they passed them the first time. The participants with DS again committed more errors than the participants in the ID and TD groups in the navigation task. In addition, they recalled fewer landmarks. While landmark identification improved landmark memory for both groups, it did not have a significant impact on navigation. Participants with DS still performed more poorly than did the TD and ID participants. Of additional interest, we observed that the performance of persons with DS correlated with different ability measures than did the performance of the other groups. The results the two experiments point to a problem in navigation for persons with DS that exceeds expectations based solely on intellectual level.