Changes in the spatial spread of attention with ageing
Abstracts:Spatial attention is a necessary cognitive process, allowing for the direction of limited capacity resources to varying locations in the visual field for improved visual processing. Thus, understanding how ageing influences these processes is vital. The current study explored the relationship between the spatial spread of attention and healthy ageing using an inhibition of return task to tap visual attention processing. This task allowed us to measure the spatial distribution of inhibition, and thus acted as a marker for attentional spread. Past research has indicated minimal age differences in inhibitory spread. However, these studies used placeholder stimuli, which may have restricted the range over which age differences could be reliably measured. To address this, in Experiment One, we measured the relationship between the spatial spread of inhibition and healthy ageing using a method which did not employ placeholders. In contrast to past research, an age difference in inhibitory spread was observed, where in comparison to younger adults, older adults exhibited a relatively restricted spread of attention. Experiment Two then confirmed these findings, by directly comparing inhibitory spread for placeholder present and placeholder absent conditions, across younger and older adults. Again, it was found that age differences in inhibitory spread emerged, but only in the placeholder absent condition. Possible reasons for the observed age differences in attention are discussed.
Can the post-error effect mask age-related differences in congruency conditions when education and overall accuracy are controlled for?
Abstracts:Age-related differences in stimulus–response congruency tasks have been attributed to older adults' greater difficulties in handling the irrelevant spatial-dimensional overlap between stimulus and response. However, performance on congruency tasks may also be influenced by the previous trial accuracy (i.e. post-error effect), which may affect young and older adults differently. The main objective of this study was to analyse age-related differences in the post-error effect as a function of congruency. In addition, we examined the meditational role of the Gratton effect on the age-related differences in the post-error slowing (PES) and post-error increased accuracy (PIA) as a function of congruency.
Configural face perception in childhood and adolescence: An individual differences approach
Abstracts:Cognitive experimental and neuroscientific research in adults indicates that an important property of face perception is its specificity and reliance on configural processing. In addition, individual differences in face perception between adults cannot be entirely explained through general cognitive functioning and object cognition. Although recent years have witnessed growing interest in the development of face perception through childhood and adolescence, as yet, little is known about individual differences in configural face perception in this period of life, and whether these differences are face-specific. Here, we addressed these questions in a large sample (N = 338) drawn continuously from age six to 21. We applied a face composite task and a spatial manipulation task including stimulus inversion. Immediate and delayed face memory were assessed as covariates of configural face perception. Content specificity in configural face perception was tested by analogous tasks with houses as stimuli. In addition, we measured working memory and fluid intelligence. Our results show that there are large individual differences in configural face perception across the entire age range from six to 21 years. Supporting theories of early maturation, configural face perception was almost adult-like already at age six. Individual differences in configural face perception were related with immediate and delayed face memory and fluid intelligence across the whole age range. In sum, we provide novel evidence on large individual differences in configural face and object perception already in middle childhood, complementing findings from aging studies and providing new perspectives for further research.
Backward crosstalk and the role of dimensional overlap within and between tasks
Abstracts:In dual-task situations, which often involve some form of sequential task processing, features of Task 2 were shown to affect Task 1 performance, a phenomenon termed “backward crosstalk effect” (BCE). Most previous reports of BCEs are based on manipulations of code compatibility between tasks, while there is no clear picture whether and how mere Task 2 response selection difficulty (in the absence of cross-task dimensional code overlap, including effector system overlap) may also affect Task 1 performance. In the present study, we systematically manipulated response-response (R1-R2) relation (compatible, incompatible, arbitrary) and the stimulus-response (S-R) relation in Task 2 (S2-R2: compatible, incompatible, arbitrary; i.e., a classic manipulation of Task 2 response selection difficulty) to study the impact of dimensional overlap and compatibility within and across tasks using an integrated stimulus for both a vocal Task 1 and a manual Task 2. Results revealed a replication of a classic (spatial) R1-R2 compatibility BCE (based on code compatibility), demonstrating that our paradigm is principally suited to capture typical BCEs. Importantly, conditions involving a removal of dimensional code overlap between tasks still yielded an effect of mere Task 2 response selection difficulty on Task 1 performance. Both types of BCEs (i.e., BCEs based on code compatibility and BCEs based on Task 2 difficulty) could be assumed to be rooted in anticipation of response selection difficulty triggered by stimuli indicating either R1-R2 or S2-R2 incompatibility. The results are in line with recent theoretical claims that anticipations of response characteristics (or effects) play an important role for BCEs in particular and for conflict resolution in action control in general.
The left hand disrupts subsequent right hand grasping when their actions overlap
Abstracts:Adaptive motor control is premised on the principle of movement minimization, which in turn is premised on a form of sensorimotor memory. But what is the nature of this memory and under what conditions does it operate? Here, we test the limits of sensorimotor memory in an intermanual context by testing the effect that the action performed by the left hand has on subsequent right hand grasps. Target feature-overlap predicts that sensorimotor memory is engaged when task-relevant sensory features of the target are similar across actions; partial effector-overlap predicts that sensorimotor memory is engaged when there is similarity in the task-relevant effectors used to perform an action; and the action-goal conjunction hypotheses predicts that sensorimotor memories are engaged when the action goal and the action type overlap. In three experiments, participants used their left hand to reach out and pick up an object, manually estimate its size, pinch it, look at it, or merely rest the left hand before reaching out to pick up a second object with their right hand. The in-flight anticipatory grip aperture of right-hand grasps was only influenced when it was preceded by grasps performed by the left-hand. Overlap in the sizes of the objects, partial overlap in the effectors used, and in the availability of haptic feedback bore no influence on this metric. These results support the hypothesis that intermanual transfer of sensorimotor memory on grasp execution is dependent on a conjunction of action type and goal.
Visual similarity modulates visual size contrast
Abstracts:Perception is relational: object properties are perceived in comparison to the spatiotemporal context rather than absolutely. This principle predicts well known contrast effects: For instance, the same sphere will feel smaller after feeling a larger sphere and larger after feeling a smaller sphere (the Uznadze effect). In a series of experiments, we used a visual version of the Uznadze effect to test whether such contrast effects can be modulated by organizational factors, such as the similarity between the contrasting inducer stimulus and the contrasted induced stimulus. We report that this is indeed the case: size contrast is attenuated for inducer-inducing pairs having different 3D shapes, orientations, and even – surprisingly – color and lightness, in comparison to equivalent conditions where these features are the same. These findings complement related work in revealing basic mechanisms for fine-tuning local interactions in space-time in accord to the global stimulus context.
The optimal viewing position effect in printed versus cursive words: Evidence of a reading cost for the cursive font
Abstracts:Two eye-movement experiments were conducted to examine the effects of font type on the recognition of words presented in central vision, using a variable-viewing-position technique. Two main questions were addressed: (1) Is the optimal viewing position (OVP) for word recognition modulated by font type? (2) Is the cursive font more appropriate than the printed font in word recognition in children who exclusively write using a cursive script? In order to disentangle the role of perceptual difficulty associated with the cursive font and the impact of writing habits, we tested French adults (Experiment 1) and second-grade French children, the latter having exclusively learned to write in cursive (Experiment 2). Results revealed that the printed font is more appropriate than the cursive for recognizing words in both adults and children: adults were slightly less accurate in cursive than in printed stimuli recognition and children were slower to identify cursive stimuli than printed stimuli. Eye-movement measures also revealed that the OVP curves were flattened in cursive font in both adults and children. We concluded that the perceptual difficulty of the cursive font degrades word recognition by impacting the OVP stability.
Effects of planning strategies on writing dynamics and final texts
Abstracts:Expert writing involves the interaction among three cognitively demanding processes: planning, translating, and revising. To manage the cognitive load brought on by these processes, writers frequently use strategies. Here, we examined the effects of planning strategies on writing dynamics and final texts. Before writing an argumentative text with the triple-task technique, 63 undergraduates were asked either to elaborate an outline with the argumentative structure embedded (structure-based planning condition), to provide a written list of ideas for the text (list-based planning condition), or to do a non-writing-related filler task (no planning condition). Planning showed no effects on the length of the pre-writing pause and cognitive effort, but influenced writing processes occurrences. Compared to participants in the no-planning condition, those in the planning conditions showed a later activation of revising. Moreover, participants in the structure-based condition were mainly focused on translating in the beginning and middle of composition, whereas their peers tended to distribute their attention among all processes. Planning ahead of writing also resulted in texts with longer words, produced at a higher rate. Only the structure-based planning strategy led to an increase in the number of argumentation elements as well as in essays' persuasiveness and overall quality. There was, however, no indication that these improvements in final texts were associated with changes in the dynamics of writing. Overall, the use of structure-based plans seems to be an effective and efficient way of improving undergraduates' argumentative writing.
Change perception and change interference within and across feature dimensions
Abstracts:The ability to perceive a change in a visual object is reduced when that change is presented in competition with other changes which are task-irrelevant. We performed two experiments which investigate the basis of this change interference effect. We tested whether change interference occurs as a consequence of some form of attentional capture, or whether the interference occurs at a stage prior to attentional selection of the task-relevant change. A modified probe-detection task was used to explore this issue. Observers were required to report the presence/absence of a specified change-type (colour, shape) in the probe, in a context in which - on certain trials - irrelevant changes occur in non-probe items. There were two key variables in these experiments: the attentional state of the observer, and the dimensional congruence of changes in the probe and non-probe items. Change interference was strongest when the irrelevant changes were the same as those on the report dimension. However the interference pattern persisted even when observers did not know the report dimension at the time the changes occurred. These results seem to rule out attention as a factor. Our results fit best with an interpretation in which change interference produces feature-specific sensory noise which degrades the signal quality of the target change.
Low-level image properties in facial expressions
Abstracts:We studied low-level image properties of face photographs and analyzed whether they change with different emotional expressions displayed by an individual. Differences in image properties were measured in three databases that depicted a total of 167 individuals. Face images were used either in their original form, cut to a standard format or superimposed with a mask. Image properties analyzed were: brightness, redness, yellowness, contrast, spectral slope, overall power and relative power in low, medium and high spatial frequencies. Results showed that image properties differed significantly between expressions within each individual image set. Further, specific facial expressions corresponded to patterns of image properties that were consistent across all three databases. In order to experimentally validate our findings, we equalized the luminance histograms and spectral slopes of three images from a given individual who showed two expressions. Participants were significantly slower in matching the expression in an equalized compared to an original image triad. Thus, existing differences in these image properties (i.e., spectral slope, brightness or contrast) facilitate emotion detection in particular sets of face images.