Infants' reasoning about opaque and transparent occluders in an individuation task

There has been some debate about whether infants 10 months and younger can use featural information to individuate objects. The present research tested the hypothesis that negative results obtained with younger infants reflect limitations in information processing capacities rather than the inability to individuate objects based on featural differences. Infants aged 9.5 months saw one object (i.e. a ball) or two objects (i.e. a box and a ball) emerge successively to opposite sides of an opaque occluder. Infants then saw a single ball either behind a transparent occluder or without an occluder. Only the infants who saw the ball behind the transparent occluder correctly judged that the one-ball display was inconsistent with the box-ball sequence. These results suggest that: (a) infants categorize events involving opaque and transparent occluders as the same kind of physical situation (i.e. occlusion) and (b) support the notion that infants are more likely to give evidence of object individuation when they need to reason about one kind of event (i.e. occlusion) than when they must retrieve and compare categorically distinct events (i.e. occlusion and no-occlusion).     

The effect of cueing on change blindness and same blindness

We used the change blindness paradigm of Landman, Spekreijse, and Lamme (2003) to measure the effect of cues on the ability to detect changes between two presentations of an array of eight rectangles separated by an interstimulus interval (ISI). Next, we measured the ability to detect sameness as the target rectangle remained the same when all of the others changed orientation. We were surprised to find no difference between change-detection and same-detection performance. These results (1) are consistent with the notion that some kind of internal representation was cued during the ISI, (2) mitigate against the recruitment of grouping strategies and/or forming a Gestalt, and (3) imply that under conditions facilitated by cues same-detection performance can be as good as change-detection performance.     

Conditions for Piagetian Stage IV search errors in a task using transparent occluders

In a Piagetian Stage IV search task in which the object was in plain view under transparent covers, Butterworth (1977) obtained errors from nearly half the infants but noted few errors when the object was uncovered. This study investigates the possibility that errors arise in the former case because novel transparent covers present a particular distraction. Butterworth's results with transparent covers were replicated under his conditions of administration, but virtually no errors were obtained when infants were familiarized with the covers prior to testing. From this and other results it is suggested that errors in search for a visible object only occur when the infant's attention is drawn by other features of the array.     

Visual distraction increases the detection of an unexpected object in inattentional blindness

Distraction is typically thought to be detrimental to performance and concentration, and stimuli are classified as “distractions” if they take attention away from a primary task. However it has been shown that, under certain circumstances, distractors can also improve task performance. The current study extends this literature by exploring the role of a single discrete transient visual distracting event in increasing attention to an unexpected visual object in an inattentional blindness (IB) paradigm. Experiment 1 investigated the impact of a 48 ms visual distraction stimulus on rates of IB; a second experiment used a shortened, 16 ms visual distracting event. Both the long 48 ms and brief 16 ms distractors significantly reduced overall IB rates, by approximately 50% compared to a no distractor condition. Moreover, this reduction in IB is obtained independent of whether the visual distracting event was noted by the observer. Our findings demonstrate that a single discrete visual distraction can improve the detectability of an unexpected object in an IB task. Implications for theories of distributed attention in such tasks are discussed.     

Attentional processes and meditation

Visual attentional processing was examined in adult meditators and non-meditators on behavioral measures of change blindness, concentration, perspective-shifting, selective attention, and sustained inattentional blindness. Results showed that meditators (1) noticed more changes in flickering scenes and noticed them more quickly, (2) counted more accurately in a challenging concentration task, (3) identified a greater number of alternative perspectives in multiple perspectives images, and (4) showed less interference from invalid cues in a visual selective attention task, but (5) did not differ on a measure of sustained inattentional blindness. Together, results show that regular meditation is associated with more accurate, efficient, and flexible visual attentional processing across diverse tasks that have high face validity outside of the laboratory. Furthermore, effects were assessed in a context separate from actual meditation practice, suggesting that meditators’ better visual attention is not just immediate, but extends to contexts separate from meditation practice.     

A review of methods in the study of attention in autism

Atypical attention, while not a diagnostic feature, is common in individuals with autism spectrum disorders (ASD). The study of these atypicalities has recently gained in both quantity and quality, due in part to an increased focus on attentional atypicalities as one of the earliest signs of ASD in infancy. A range of attentional processes and components have been investigated, and the methods used are varied, from Posner-type paradigms, to the more recent use of eye-movement recording and change-detection techniques. This methodological complexity is one factor in the production of conflicting evidence on the topic of attention in ASD. This review uses a focus on methodology to clarify the literature to date and provide a resource for researchers wishing to study attention in ASD. Other factors that have contributed to the current discrepancies in findings are discussed, particularly the role of individual and group differences within the population of people with ASD.     

Crossmodal change blindness between vision and touch

Change blindness is the name given to people's inability to detect changes introduced between two consecutively-presented scenes when they are separated by a distractor that masks the transients that are typically associated with change. Change blindness has been reported within vision, audition, and touch, but has never before been investigated when successive patterns are presented to different sensory modalities. In the study reported here, we investigated change detection performance when the two to-be-compared stimulus patterns were presented in the same sensory modality (i.e., both visual or both tactile) and when one stimulus pattern was tactile while the other was presented visually or vice versa. The two to-be-compared patterns were presented consecutively, separated by an empty interval, or else separated by a masked interval. In the latter case, the masked interval could either be tactile or visual. The first experiment investigated visual-tactile and tactile-visual change detection performance. The results showed that in the absence of masking, participants detected changes in position accurately, despite the fact that the two to-be-compared displays were presented in different sensory modalities. Furthermore, when a mask was presented between the two to-be-compared displays, crossmodal change blindness was elicited no matter whether the mask was visual or tactile. The results of two further experiments showed that performance was better overall in the unimodal (visual or tactile) conditions than in the crossmodal conditions. These results suggest that certain of the processes underlying change blindness are multisensory in nature. We discuss these findings in relation to recent claims regarding the crossmodal nature of spatial attention.     

Priming infants to attend to color and pattern information in an individuation task

Wilcox (Cognition 72 (1999) 125) reported that infants are more sensitive to form than surface features when individuating objects in occlusion events: it is not until 7.5 months that infants spontaneously use pattern information, and 11.5 months that they spontaneously use color information, as the basis for object individuation. The present research assessed the extent to which infants' sensitivity to surface features could be increased under more supportive conditions. More specifically, we examined whether younger infants could be primed to draw on color and pattern features in an individuation task if they were first shown the functional value of attending to color and pattern information (i.e. the color or the pattern of an object predicted the function it would engage in). Five experiments were conducted with infants 4.5 to 9.5 months of age. The main findings were that 9.5- and 7.5-month-olds could be primed to use color information, and 5.5- and 4.5-month-olds could be primed to attend to pattern information, after viewing the function events. The results are discussed in terms of the kinds of experiences that can lead to increased sensitivity to surface features and the mechanisms that support feature priming in young infants.     

Culture and change blindness

Research on perception and cognition suggests that whereas East Asians view the world holistically, attending to the entire field and relations among objects, Westerners view the world analytically, focusing on the attributes of salient objects. These propositions were examined in the change-blindness paradigm. Research in that paradigm finds American participants to be more sensitive to changes in focal objects than to changes in the periphery or context. We anticipated that this would be less true for East Asians and that they would be more sensitive to context changes than would Americans. We presented participants with still photos and with animated vignettes having changes in focal object information and contextual information. Compared to Americans, East Asians were more sensitive to contextual changes than to focal object changes. These results suggest that there can be cultural variation in what may seem to be basic perceptual processes.     

How something can be said about telling more than we can know: on choice blindness and introspection

The legacy of Nisbett and Wilson’s classic article, Telling More Than We Can Know: Verbal Reports on Mental Processes (1977), is mixed. It is perhaps the most cited article in the recent history of consciousness studies, yet no empirical research program currently exists that continues the work presented in the article. To remedy this, we have introduced an experimental paradigm we call choice blindness [Johansson, P., Hall, L., Sikström, S., &; Olsson, A. (2005). Failure to detect mismatches between intention and outcome in a simple decision task. Science, 310(5745), 116–119.]. In the choice blindness paradigm participants fail to notice mismatches between their intended choice and the outcome they are presented with, while nevertheless offering introspectively derived reasons for why they chose the way they did. In this article, we use word-frequency and latent semantic analysis (LSA) to investigate a corpus of introspective reports collected within the choice blindness paradigm. We contrast the introspective reasons given in non-manipulated vs. manipulated trials, but find very few differences between these two groups of reports.     

Aging and performance on an everyday-based visual search task

Research on aging and visual search often requires older people to search computer screens for target letters or numbers. The aim of this experiment was to investigate age-related differences using an everyday-based visual search task in a large participant sample (n=261) aged 20-88 years. Our results show that: (1) old-old adults have more difficulty with triple conjunction searches with one highly distinctive feature compared to young-old and younger adults; (2) age-related declines in conjunction searches emerge in middle age then progress throughout older age; (3) age-related declines are evident in feature searches on target absent trials, as older people seem to exhaustively and serially search the whole display to determine a target's absence. Together, these findings suggest that declines emerge in middle age then progress throughout older age in feature integration, guided search, perceptual grouping and/or spreading suppression processes. Discussed are implications for enhancing everyday functioning throughout adulthood.     

Color-function categories that prime infants to use color information in an object individuation task

There is evidence for developmental hierarchies in the type of information to which infants attend when reasoning about objects. Investigators have questioned the origin of these hierarchies and how infants come to identify new sources of information when reasoning about objects. The goal of the present experiments was to shed light on this debate by identifying conditions under which infants’ sensitivity to color information, which is slow to emerge, could be enhanced in an object individuation task. The outcome of Experiment 1 confirmed and extended previous reports that 9.5-month-olds can be primed, through exposure to events in which the color of an object predicts its function, to attend to color differences in a subsequent individuation task. The outcomes of Experiments 2-4 revealed age-related changes in the nature of the representations that support color priming. This is exemplified by three main findings. First, the representations that are formed during the color-function events are relatively specific. That is, infants are primed to use the color difference seen in the color-function events to individuate objects in the test events, but not other color differences. Second, 9.5-month-olds can be led to form more abstract event representations, and then generalize to other colors in the test events if they are shown multiple pairs of colors in the color-function events. Third, slightly younger 9-month-olds also can be led to form more inclusive categories with multiple color pairs, but only when they are allowed to directly compare the exemplars in each color pair during the present events. These results shed light on the development of categorization abilities, cognitive mechanisms that support color-function priming, and the kinds of experiences that can increase infants’ sensitivity to color information.     

The chronometry of mental ability: An event-related potential analysis of an auditory oddball discrimination task

The relation between intelligence and speed of auditory discrimination was investigated during an auditory oddball task with backward masking. In target discrimination conditions that varied in the interval between the target and the masking stimuli and in the tonal frequency of the target and masking stimuli, higher ability participants (HA) displayed more accurate discriminations, faster response time, larger P300 amplitude, and shorter P300 and mismatch negativity (MMN) latency than lower ability participants (LA). Task difficulty effects demonstrated with variation in mask type indicate that the mask does not interfere with the detection of the deviant target stimulus, but rather that the target and mask are integrated as a single compound stimulus. The temporal effects suggest that the speed of accessing short-term memory is faster for HA than LA and, on the basis of the MMN latency, the effect is accomplished automatically, without focused attention. Moreover, the pattern of results obtained with these data support the view that the accuracy effects are determined by processing speed rather than discrimination ability. Comparator models that accommodate these effects are discussed.     

Perspective taking and cognitive flexibility in the Dimensional Change Card Sorting (DCCS) task

In a study with 79 3-year-olds, we confirm earlier findings that separating the sorting dimensions improve children's performance on the Dimensional Change Card Sorting (DCCS) task. We also demonstrate that the central reason for this facilitation is that the two sorting dimensions are not integral features of a single object. Spatial separation of the sorting dimensions has no additional significant influence. This finding highlights the important role of objects with respect to children's attentional flexibility. Implications for current theories on the DCCS task and for the development of perspective taking and cognitive flexibility are discussed.     

Temperamental contributions to children's performance in an emotion-word processing task: a behavioral and electrophysiological study

Seven-year-old children (N=65) participating in a study of the influence of infant temperament on socioemotional development performed an auditory selective attention task involving words that varied in both affective (positive vs. negative) and social (social vs. nonsocial) content. Parent report of contemporaneous child temperament was also collected, and individual differences in self-regulation in the affective (soothability) and cognitive (attentional control) domains were noted. Overall, children showed slower responses to stimuli that were either social or negative in content, with the largest effect elicited by words that possessed both traits. Children rated high in soothability and attentional control showed slower responses to social negative words. The other children showed little to no differential response patterns across the word categories. ERPs collected during the task indicated that processing differences were evident in the later more cognitive components of the ERP, especially in children low in attentional control. These findings indicate that performance on an auditory selective attention task can assist in identifying underlying patterns of affective processing.     

Effects of perspective and belief on analytic reasoning in a scientific reasoning task

The purpose of these studies was to test the hypothesis that changing perspectives from one's own to another's promotes the engagement of analytic processing and, in turn, reduces the impact of beliefs. In two experiments participants evaluated research vignettes containing belief-consistent and belief-inconsistent conclusions, and indicated whether the data supported a correlation between two variables. Consistent with our hypothesis, the tendency to endorse correlations consistent with prior belief was reduced when participants evaluated the data from the researcher's perspective relative to their own. We also administered the Actively Open Minded Thinking (AOT) scale (Stanovich & West, 2007, 2008), which did not predict belief effects on our task. We did however observe that the AOT was reliably associated with different response strategies: high AOT scorers were more inclined to choose ambiguous response options, such as “no conclusion is warranted”, whereas low scorers evinced a preference for more determinate options (e.g., there is no relationship between the two variables). We interpret our findings in the context of dual process theories of reasoning and from a Bayesian perspective.     

Infants' sensitivity to correlations between static and dynamic features in a category context

Four experiments with the habituation procedure investigated 14-22-month-olds' ability to attend to correlations between static and dynamic features embedded in a category context. In Experiment 1, infants were habituated to four objects that exhibited invariant relations between moving features and motion trajectory. Results revealed that 14-month-olds did not process any independent features, 18-month-olds processed individual features but not relations among features, and 22-month-olds processed relations among features. In Experiment 2, 14-month-olds differentiated all of the features in the events in a simpler discrimination task. In Experiments 3a and 3b, 22-month-olds failed to show sensitivity to correlations between dynamic and static features in a category context. In Experiment 4, 22-month-olds, but not 18-month-olds, generalized the learned feature-motion relation to a novel instance. The results are discussed in relation to infants' developing ability to attend to correlations, constraints on learning, category coherence, and the development of the animate-inanimate distinction.     

Comparing infants' use of featural and spatiotemporal information in an object individuation task using a new event-monitoring design

Discussions have recently taken place on whether spatiotemporal information is more important than featural information when infants attempt to individuate objects. Hitherto, spatiotemporal and featural information have only been compared directly by using cognitively demanding 'event-mapping designs' (e.g. Xu & Carey, 1996), whereas the simpler event-monitoring designs (e.g. the 'wide-screen/narrow-screen' by Wilcox and colleagues) have not been employed for such a comparison. The present research offers a new event-monitoring design, the rotating screen design, that allows for such a direct comparison. Three experiments in which 9.5-, 8.0-, and 6.5-month-old infants attempt to individuate objects by spatiotemporal and featural information are reported. The results showed that whereas the 9.5-month-old infants were able to individuate objects by spatiotemporal as well as featural information, the infants of the younger age groups only successfully individuated objects when provided with spatiotemporal information, but not with featural information.     

Speed of information-processing in an inductive reasoning task and its relationship to psychometric intelligence

The relationship between psychometric intelligence (measured by means of Raven's Advanced Progressive Matrices and two verbal subtests of the “Intelligenz-Struktur-Test-70”) and speed of information-processing in a newly developed computerized reaction time (RT) task called the Concept-Verification-Test (CVT) was investigated in a sample of 104 undergraduates. In this CVT, first, one of five possible conceptual rules is presented on a computer monitor. After reading the rule, the subject has to press a button and then one of 27 possible simple geometrical figures is presented, which either is an example of the concept or not. The subject has to press the true button if the presented figure is a positive instance of the rule or the false button if it is not. Two RTs were measured: The Comprehension Reaction Time (CRT) from the onset of the rule to the first button press and the Verification Reaction Time (VRT) from the onset of the figure until the response is given. The different complexity of the conceptual rules used also allowed us to examine the “complexity hypothesis” (i.e. correlations with intelligence should be higher for more complex RT tasks). As predicted, both CRTs and VRTs correlated negatively with intelligence, but we found no evidence for the validity of the complexity hypothesis.     

Attention capacity and task difficulty in visual search

When a visual search task is very difficult (as when a small feature difference defines the target), even detection of a unique element may be substantially slowed by increases in display set size. This has been attributed to the influence of attentional capacity limits. We examined the influence of attentional capacity limits on three kinds of search task: difficult feature search (with a subtle featural difference), difficult conjunction search, and spatial-configuration search. In all 3 tasks, each trial contained sixteen items, divided into two eight-item sets. The two sets were presented either successively or simultaneously. Comparison of accuracy in successive versus simultaneous presentations revealed that attentional capacity limitations are present only in the case of spatial-configuration search. While the other two types of task were inefficient (as reflected in steep search slopes), no capacity limitations were evident. We conclude that the difficulty of a visual search task affects search efficiency but does not necessarily introduce attentional capacity limits.