The detection of human and non-human animals and their unique (and potentially dangerous) “animation” would have been important to our ancestors’ survival. It would seem plausible that our ancestors would have required a vigilance above and beyond that dedicated to other, inanimate, objects. Considering the millions of years of expending extra energy to monitor these objects, it would also seem likely, at least as advocated by New, Cosmides, and Tooby (2007), that the human visual system would have developed mechanisms to allocate attention automatically and quickly to these objects. We tested the New et al. (2007) “animate monitoring” hypothesis by presenting viewers with a group of animate objects and a group of inanimate objects using the flicker task—a task that is assumed to be one that measures automatic visual attention. These objects were presented on a variety of backgrounds of natural scenes, including some backgrounds that were contextually inconsistent with the target objects. These objects were also presented in either a consistent location within each scene or a location that violated that consistency. Only people objects were consistently more readily detected, not animated objects in general. Detection in this task was affected by more than just the information provided by the target object. Both results provide a serious challenge to the “animate monitoring” hypothesis. Furthermore, the results were shown not to be due to peculiarities of our stimulus set, or by how interesting the members of each object category were. iv / xii, 108 leaves ; 29 cm

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A forced choice reaction time (RT) task was used to assess developmental changes in filtering and the related ability to narrow the focus of the attentional lens among persons with autism as compared to a group of typically developing children matched on different standardized measures. The participants included 35 persons with autism (CAs between 8.3 and 13.2 years, M = 9.8 years) and 35 typically developing children (CAs between 4.8 and 7.3 years, M = 5.9 years) between the mental ages (MA) of 5 and 8 years. The measures used for matching include the Leiter International Performance Scale - Revised (Leiter-R; Roid and Miller, 1997), the Peabody Picture Vocabulary Test - Third Edition (PPVT-III; Dunn and Dunn, 1997), and the Expressive One Word Vocabulary Test (EOWVT; Gardner, 1990). The conditions varied with regard to the presence or absence of distractors, their proximity (none, close, and far) to a target stimulus, and the presence or absence of a visual window within which the target stimulus was presented. (Abstract shortened by UMI.)

Selective attention involves focusing on one event among many, and is largely responsible for an organism's ability to respond efficiently to the environment. The location at which attention is focused is a function of an ongoing tension between external cues and internal goals. Control over selective attention is often described as an executive process, attributable to the function of the frontal lobes of the brain. The present experiments investigated the role of the frontal cortex in attentional control, through the study of patients with focal cortical lesions and through functional neuroimaging in neurologically normal subjects. It was found that patients with unilateral surgical resections from the frontal cortex were as efficient as patients with temporal-lobe resections and normal controls at attending selectively to a visual stimulus at one location in the presence of irrelevant distracting stimuli. In fact, those patients whose lesions invaded the anterior cingulate gyrus tended to be less reactive to changes in irrelevant stimuli. However, patients with frontal cortex lesions were mildly impaired in a different task in which they used visual cues to direct attention voluntarily to a different location from one trial to the next. In addition, patients with excisions from the right frontal cortex performed less efficiently with increasing time spent on a task, suggesting an important role for this region in sustained attention. These observations prompted a further study of attention using positron emission tomography in normal subjects. This experiment was designed to identify the brain regions that were more active during trials in which cues could be used to direct attention voluntarily, relative to trials in which uninformative cues were presented. The striatum and extrastriate cortex were the only regions in which blood flow correlated positively with the proportion of trials containing informative cues. The present studies indicate that the frontal

Research has shown that at least half of children who display problem behaviour in preschool maintain these behaviour patterns when they reach school age. Without targeted intervention these behaviours may lead to an antisocial developmental pathway and problem behaviours which become increasingly entrenched and unlikely to respond to treatment. The present study had two aims, the first was to evaluate the use of differential attention as a behaviour management strategy in a preschool setting and to assess its effectiveness in encouraging prosocial behaviour in children who require extra assistance with their social development. The second was to assess the extent to which groups of Early Education teachers were able to implement differential attention during structured mat times and eating periods. This was achieved by observing both child appropriate and inappropriate behaviour and teacher attention to child appropriate and inappropriate behaviour. The study found that when teachers increased their rate of attention to appropriate behaviour to a level greater that their rate of attention to inappropriate behaviour, the child’s behaviour changed with appropriate behaviour increasing and inappropriate behaviour decreasing. Child behaviour only changed when teachers behaviour changed and was only maintained in the cases where teachers’ behaviour was maintained. One of the most significant observations in the study was the variability in implementation of the differential attention procedure across teachers and centres, leading to a number of recommendations for future research in preschool settings.

Children with ADHD have significant attentional problems that affect their academic performance. Because many of the typical symptoms of ADHD manifest themselves in classrooms, these attentional problems may have an impact on comprehension and its course of development. This is a significant area of interest because the academic success of a child requires being able to recall and comprehend information. Effective comprehension requires being able to understand both causal (why?) and factual (what?) questions. The purposes of this study are use the television viewing methodology and 1) to employ a longitudinal investigation and compare patterns of developmental change among children with ADHD and comparison children in attention and comprehension, 2) examine if cognitive engagement, as indexed by long looks, increases with age for each group, and 3) investigate how look lengths relate to comprehension for each group. Participants were 59 children with ADHD and 101 comparison children. Children viewed two 12-minute episodes of the Rugrats television program at time one and two episodes at time two, approximately 18-months later. Each of the children viewed the television program in one of two viewing conditions, toys-present and toys-absent. Results provide insight into the problems in attention and comprehension experienced by children with ADHD. First, the preciously observed difficulties in sustaining attention with toys-present for children with ADHD are stable across time and a wide age range. Second, as they got older children with ADHD did not exhibit the same increase in time spent in long looks as comparison children. Third, the older high IQ children with ADHD fell behind comparison children in their recall of factual information as they got older. Fourth, as they became older, high IQ children with ADHD did not show improvement in their causal recall with toys present, in contrast to comparison children. Finally, although there was some support for the hypothesis that time spent in long looks is associated with comprehension of the televised material, it did not account for group differences in recall. Several implications and directions for future research are discussed.

An inhibition-based fan effect was explored with two different negative priming tasks. Experiment 1 used a modified flanker-type colour blob task in both children and adults (Pritchard & Neumann, 2004), where two additional conditions were included (C2 and IR2). Each set of the colour blobs for the additional conditions consist of two distractor colours instead of one distractor colour. Experiment 2 used Navon’s (1977) global-local letter task, where a global letter contains one, two, or three local letters as distractors to see if an inhibitory fan effect operated on the should-be-ignored local letters. Results from both experiments did not support for the inhibition-based fan effect hypothesis. However, in line with Pritchard and Neumann (2004) and Frings et al. (2007), there was evidence for the claim that selective control mechanism are developed much earlier in young children than previously thought.

Neurologically healthy individuals misbisect their visual space by erring towards the left. This misreprentation has been attributed to the right hemisphere dominance in processing of spatial information. Lateral biases are thought to emerge as behavioural outcomes of cognitive processing, mainly attention. Recently, attention mechanisms have been reported to be closely inter-related to memory systems, where attention directs what will be remembered and memory impacts where attention is directed. Although spatial biases attributed to attention have been widely accepted, the claim that memory exhibits similar biases has been more controversial. Recent research shows that recall of representations is biased towards the left side of space, indicating that lateral asymmetries may not necessarily be limited to perceptual and attentional mechanisms, but may extend to memory mechanisms as well. The purpose of this work is to understand better the relationship between lateral biases within working memory and attention interactions. Two approaches were considered. First, working memory, as defined by the representations and operations related to manipulate the representations, used time delay and visual load. Second, backward masking was used to control the relative formation of the working memory trace, which strengthens with recurrence of the visual stimuli and is through to progress from attention to working memory. To explore these two theoretical avenues, a novel task was constructed. Two circular arrays were presented at the top and bottom of the computer screen. These arrays were composed of six individual discs of varying shade. Hence, the overall array represented a greyscale gradient, where discs on one lateral side were darker compared to the middle discs and the other lateral side. For example, if two darkest discs were presented on the left side, the lightest discs were presented on the right side. Such array was presented with its left/right mirror reversed image. In this example, the second array was with the lightest discs on the left side and growing progressively darker, with darkest discs on the right side. Such presentation requires the participants to integrate the array of individual discs into an overall representation to perform a brightness judgement and select the array seemingly darker. A total of six behavioural studies addressed the two theoretical approaches. The first approach, to determine the impact of inter-stimulus time interval and visual load on lateral asymmetries, was addressed in four experiments. The findings indicated that participants were able to integrate the discrete disks into an overall array. Participants exhibited an overall leftward bias similar to that obtained in attention tasks, where they selected an array to be overall darker when the darkest disks were presented on the left side of the array. Furthermore, these biases increased the most when the stimuli were presented in the lower half of the computer screen, consistent with the lower visual field. Conversely, stimuli presented to the upper half of the screen elicited a rightward bias, which is consistent with the upper visual field. Stronger biases were observed when the stimulus noise, in the form of black, white and grey pixels, was relatively low and weaker biases were attained with a relatively high noise levels. In the second study, the findings showed that the magnitude of upper and lower visual field biases shows dependence on the vertical and lateral stimulus manipulation within these fields. Upper-left, lower-right interactions indicate that biases may not simply rely on the horizontal and vertical dimensions, as previously thought, but also on the relative spatial distribution of stimuli within these dimensions. The third study, which used the standard rectangular greyscale stimuli, revealed that visual load does not impact the lateral biases, but shows to impact the upper and lower visual field processing. Further, time interval between stimulus presentation and response, extended past 1 second eliminated lateral and vertical biases. The remaining two studies investigated lateral asymmetries within working memory by selectively manipulating the formation of working memory trace using backward masks. The presence of a mask, following a stimulus, inhibits the memory trace formation for that stimulus. Conversely, if no mask is presented following the stimuli, the memory trace is permitted to form within working memory. Again, using the circular array task, participants were required to select the overall darker array while retaining either a shade of position information from the array within their working memory. Findings showed increased rightward biases when memory trace was permitted to form with longer inter-stimulus (3 sec) time interval, as compared to shorter (0 to 1 sec) time interval. In the last study, the participants were required to make brightness judgement while maintaining either a position or shade information within working memory to determine whether previously acquired information, which does not serve as a cue, impact the brightness judgement task. Rightward biases were evident when participants were required to maintain either a position or shade information relating to the array, but did not provide any cue-type of information, which could facilitate performance. Rightward biases were stronger while retaining position information and completing the brightness task, hence indicating a spatial nature of the bias. As well, stronger rightward biases were obtained when the to-be-remembered position information was allowed to create a memory trace. Furthermore, recall accuracy of the position information was increased when the memory trace was permitted to form, indicating involvement of working memory processes. Overall, the data attained in this set of experiments can be interpreted using the activation-orientation model presented by Reuter-Lorenz (1990) indicating that this model may also be valuable when integrating working memory in addition to attentional processes.