Showing papers by "Jan W. de Fockert published in 2012"

Focusing on Attention: The Effects of Working Memory Capacity and Load on Selective Attention

Abstract: Background Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention. Methodology/Principal Findings In Experiment 1, distractibility from a distractor at a fixed distance from the target was greater when either WML was high or WMC was low, but surprisingly smaller when both WML was high and WMC low. Thus we observed an inverted-U relationship between reductions in WM resources and distractibility. In Experiment 2, we mapped the distribution of spatial attention as a function of WMC and WML, by recording distractibility across several target-to-distractor distances. The pattern of distractor effects across the target-to-distractor distances demonstrated that the distribution of the attentional window becomes dispersed as WM resources are limited. The attentional window was more spread out under high compared to low WML, and for low compared to high WMC individuals, and even more so when the two factors co-occurred (i.e., under high WML in low WMC individuals). The inverted-U pattern of distractibility effects in Experiment 1, replicated in Experiment 2, can thus be explained by differences in the spread of the attentional window as a function of WM resource availability. Conclusions/Significance The current findings show that limitations in WM resources, due to either WML or individual differences in WMC, affect the spatial distribution of attention. The difference in attentional constraining between high and low WMC individuals demonstrated in the current experiments helps characterise the nature of previously established associations between WMC and controlled attention.

Working memory load can both improve and impair selective attention: evidence from the Navon paradigm.

Abstract: Selective attention to relevant targets has been shown to depend on the availability of working memory (WM). Under conditions of high WM load, processing of irrelevant distractors is enhanced. Here we showed that this detrimental effect of WM load on selective attention efficiency is reversed when the task requires global- rather than local-level processing. Participants were asked to attend to either the local or the global level of a hierarchical Navon stimulus while keeping either a low or a high load in WM. In line with previous findings, during attention to the local level, distractors at the global level produced more interference under high than under low WM load. By contrast, loading WM had the opposite effect of improving selective attention during attention to the global level. The findings demonstrate that the impact of WM load on selective attention is not invariant, but rather is dependent on the level of the to-be-attended information.

The role of perceptual load in action affordance by ignored objects.

Abstract: The extent to which an irrelevant distractor is processed during selective attention depends critically on the level of perceptual load on the relevant task. Here we show that perceptual load also affects the tendency of graspable objects to afford associated actions. Participants carried out a letter-search task and identified a target letter with the right or left hand while ignoring a graspable object with a handle oriented on the left or the right side of the object. The target letter was presented either on its own (low perceptual load) or alongside five nontarget letters (high load). Responses were faster when the action afforded by the ignored object was compatible (vs. incompatible) with the current target response, but only when the perceptual load of the letter search task was low. This finding is the first to demonstrate the role of perceptual load in action affordances by ignored objects.

Does local/global perceptual bias tell us anything about local/global selective attention?

Abstract: Local/global perceptual bias refers to the tendency to prioritize the processing of either local elements of a figure or its global configuration. Recent studies have shown that, compared to Wester...

The effects of using ticks and crosses on academic self-concept.

Abstract: Behaviour, including academic performance, can be influenced by implicit primes; and both objective performance and subjective ratings are susceptible to priming effects. Here, we report a new priming effect on academic self-ratings. Participants twice completed a measure of academic self-concept. In the first session, they all used circles to answer questions regarding their own perceived academic ability. In the second session, half of the participants answered with ticks (often used to indicate a correct answer in academic feedback) and the other half with crosses (often used to indicate an incorrect answer in academic feedback). Participants who used crosses had significantly lower academic self-ratings compared to the first session. No such reduction in academic self-rating was observed in participants who used ticks. Moreover, response mode only affected the academic self-concept, and self-ratings regarding physical self-concept were unaffected by response mode. None of the participants reported awareness of the response mode manipulation.