Truth table tasks: Irrelevance and cognitive ability

Two types of truth table task are used to examine people's mental representation of conditionals. In two within-participants experiments, participants either receive the same task-type twice (Experiment 1) or are presented successively with both a possibilities task and a truth task (Experiment 2). Experiment 3 examines how people interpret the three-option possibilities task and whether they have a clear understanding of it. The present study aims to examine, for both task-types, how participants' cognitive ability relates to the classification of the truth table cases as irrelevant, and their consistency in doing so. Looking at the answer patterns, participants' cognitive ability influences their classification of the truth table cases: A positive correlation exists between cognitive ability and the number of false-antecedent cases classified as “irrelevant”, both in the possibilities task and the truth task. This favours a suppositional representation of conditionals.     

Truth table tasks: The relevance of irrelevant

Two types of truth table tasks are used investigating mental representations of conditionals: a possibilities-based and a truth-based one. In possibilities tasks, participants indicate whether a situation is possible or impossible according to the conditional rule. In truth tasks participants evaluate whether a situation makes the rule true or false, or is irrelevant with respect to the truth of the rule. Comparing the two-option version of the possibilities task with the truth task in Experiment 1, the possibilities task yields logical answer patterns whereas the truth task yields defective patterns. Adding the irrelevant option to the possibilities task in Experiment 2 leads to a considerable amount of defective patterns in the possibilities task, but still to more logical patterns in the possibilities task than in the truth task. Experiment 3 shows that directionality matters since rule-to-situation tasks yield more logical answer patterns than do situation-to-rule tasks. We conclude that both task types are not comparable as such since wording, number of options and directionality influence the results.     

Some effort for some: Further evidence that scalar implicatures are effortful

Under the assumption of the principle of cooperation (Grice, 1989), a statement such as “some eels are fish” is thought to be false since it contains less information than is considered sufficient. However, the statement is logically sound since the meaning of “some” is compatible with “all”. Currently, the primary interpretation of such underinformative statements remains subject to debate. According to Levinson (2000 Levinson, S. 2000. Presumptive meanings: The theory of generalised conversational implicature, Cambridge, MA: MIT Press.  [Google Scholar]), the pragmatic “some but not all” interpretation is the default interpretation, while others (e.g., Sperber & Wilson, 1995) argue that this pragmatic interpretation only comes to the fore when relevant within the context and is thus considered secondary to the logical “some and perhaps all” interpretation. In this study, three factors that may influence the answer pattern are studied: task load, working memory capacity, and repetition of the statements. In Experiment 1, we used a secondary task paradigm to manipulate the cognitive load under which a number of underinformative statements had to be judged. We observed that for participants with a rather limited working memory span it is harder to reach a pragmatic interpretation under cognitive load. In Experiment 2, we manipulated the repetition of the statements. We observed that with a higher number of filler statements, participants produced fewer consistent answer patterns. This study provides further evidence against the automaticity of the pragmatic interpretation: It shows that the pragmatic interpretation requires more cognitive effort than the logical interpretation and that increasing the number of filler statements inhibits the development of a response strategy.     

Release of inattentional blindness by high working memory load: elucidating the relationship between working memory and selective attention

An unexpected stimulus often remains unnoticed if attention is focused elsewhere. This inattentional blindness has been shown to be increased under conditions of high memory load. Here we show that increasing working memory load can also have the opposite effect of reducing inattentional blindness (i.e., improving stimulus detection) if stimulus detection is competing for attention with a concurrent visual task. Participants were required to judge which of two lines was the longer while holding in working memory either one digit (low load) or six digits (high load). An unexpected visual stimulus was presented once alongside the line judgment task. Detection of the unexpected stimulus was significantly improved under conditions of higher working memory load. This improvement in performance prompts the striking conclusion that an effect of cognitive load is to increase attentional spread, thereby enhancing our ability to detect perceptual stimuli to which we would normally be inattentionally blind under less taxing cognitive conditions. We discuss the implications of these findings for our understanding of the relationship between working memory and selective attention.     

Trait Intellect Predicts Cognitive Engagement: Evidence from a Resource Allocation Perspective

Trait Intellect, one of the two ‘aspects’ of the broader Openness/Intellect ‘domain’, predicts performance on a range of cognitive tasks including tests of intelligence and working memory. This has been explained in terms of the tendency for high‐Intellect individuals to explore, or engage more effortfully with, abstract information. This theoretical perspective can be framed in the language of Resource Allocation Theory, in terms of high‐Intellect individuals allocating more of their available cognitive resources to abstract cognitive tasks. In two experiments (total N = 160), we examined the relation between Intellect and cognitive engagement during a primary word‐search task under conditions of both high and low secondary cognitive load. Both experiments revealed that high‐Intellect individuals were more vulnerable to the impact of the secondary cognitive load on primary task performance. This suggests that, under low secondary load, such individuals were indeed allocating more of their available cognitive resources to the primary task. These results held after controlling for trait Openness, trait Industriousness (an aspect of Conscientiousness) and a measure of working memory capacity (N‐back task). Our findings provide novel support for the cognitive mechanisms proposed to underlie trait Intellect. Copyright © 2016 European Association of Personality Psychology     

The smart potential behind probability matching

Probability matching is a classic choice anomaly that has been studied extensively. While many approaches assume that it is a cognitive shortcut driven by cognitive limitations, recent literature suggests that it is not a strategy per se, but rather another outcome of people’s well-documented misperception of randomness. People search for patterns even in random sequences, which results in probability matching at the outcome level. Previous studies have supported this by the finding that distracting people with a secondary verbal working memory task presumably prevents the pattern search, resulting in more maximizing behavior that is considered more rational. The current paper demonstrates with two experiments that there is actually truth in both accounts. For some participants, probability matching indeed seems to be the result of a cognitive shortcut, a simple “win-stay, lose-shift” strategy, and in one experiment identified these as participants low in working memory capacity. For others, however, a potentially smart pattern search strategy underlies probability matching. These probability matchers (who still look irrational in the absence of patterns) actually have a higher chance of finding a pattern if one exists. Contrary to the almost uniformly negative perception of probability matching, we therefore conclude that there can be a potentially smart strategy behind probability matching.     

Updating working memory in aircraft noise and speech noise causes different fMRI activations

The present study used fMRI/BOLD neuroimaging to investigate how visual‐verbal working memory is updated when exposed to three different background‐noise conditions: speech noise, aircraft noise and silence. The number‐updating task that was used can distinguish between “substitution processes,” which involve adding new items to the working memory representation and suppressing old items, and “exclusion processes,” which involve rejecting new items and maintaining an intact memory set. The current findings supported the findings of a previous study by showing that substitution activated the dorsolateral prefrontal cortex, the posterior medial frontal cortex and the parietal lobes, whereas exclusion activated the anterior medial frontal cortex. Moreover, the prefrontal cortex was activated more by substitution processes when exposed to background speech than when exposed to aircraft noise. These results indicate that (a) the prefrontal cortex plays a special role when task‐irrelevant materials should be denied access to working memory and (b) that, when compensating for different types of noise, either different cognitive mechanisms are involved or those cognitive mechanisms that are involved are involved to different degrees.     

Influence of response prepotency strength, general working memory resources, and specific working memory load on the ability to inhibit predominant responses: a comparison of young and elderly participants

One conception of inhibitory functioning suggests that the ability to successfully inhibit a predominant response depends mainly on the strength of that response, the general functioning of working memory processes, and the working memory demand of the task (Roberts, Hager, & Heron, 1994). The proposal that inhibition and functional working memory capacity interact was assessed in the present study using two motor inhibition tasks (Go/No-Go and response incompatibility) in young and older participants. The strength of prepotency was assessed with a short or long training phase for the response to be inhibited. The influence of working memory resources was evaluated by administering the tasks in full vs. divided attention conditions. The effect of working memory load was manipulated by increasing the number of target and distracter items in each task. Results showed no effect of prepotency strength, whereas dividing attentional resources and increasing working memory load were associated with greater inhibitory effects in both groups and for both tasks. This deleterious effect was higher for older participants, except in the working memory load condition of the Go/No-Go task. These results suggest an interactive link between working memory and response inhibition by showing that taxing working memory resources increases the difficulty of inhibiting prepotent responses in younger and older subjects. The additional detrimental effect of these factors on healthy elderly subjects was related to their decreased cognitive resources and to their shorter span size.     

从表征和认知过程上看表象与知觉、记忆的关系

表象、知觉和记忆是一个整合的认知系统。由于知觉和记忆提供了表象生成的材料,因而三者共享相似的表征,并激活广泛而相似的脑区。然而在认知加工过程上三者存在一定的差异。与知觉相比,表象的编码方式更抽象、更依赖过去经验的参与且处理细节能力更弱;与记忆相比,表象更容易受无关信息的干扰。未来对三者关系的研究应关注不同来源和不同类型的表象与知觉、记忆之间的关系,以及工作记忆在三者关系中所起的作用。     

Scanning memory for multidimensional stimuli with extended practice

Memory load and the similarity between positive and negative sets were varied orthogonally in an information-reduction task which required S to respond either “yes” or “no” to the question of whether or not a visually displayed two-dimensional pattern had been contained in a previously memorized set of patterns. Six Sa were given 8 days of practice. The results showed that throughout practice, there was a significant increase in reaction time with increaaes in the similarity of positive and neptive sets. The memory load differences sipificantly decreaaed to zero with practice, and this drop was independent of the similarity effect.. It was concluded that extended practice influences memory load differences and effects that reflect the complexity of the memory comparison process differentially.     

Retrieval of autobiographical memories: The mechanisms and consequences of truncated search

Five studies examined the extent to which autobiographical memory retrieval is hierarchical, whether a hierarchical search depends on central executive resources, and whether retrieving memories that are “higher” in the hierarchy impairs problem‐solving ability. The first study found that random generation (assessed using a button‐pressing task) was sensitive to changes in memory load (digit span). The second study showed that when participants fail to retrieve a target event, they respond with a memory that is higher up the hierarchy. The third study showed that memory is more generic only when participants use low imageable cues under cognitive load. The final two experiments showed that experimental manipulation of memory specificity affects problem solving (MEPS performance). The data are consistent with Conway and Pleydell‐Pearce's hierarchical retrieval model of autobiographical memory, and suggest that overgeneral memory in nonclinical participants is associated with reduced executive capacity only when retrieval is “top‐down” (generative).     

负荷越大，转换更难-来自数字大小交替比较的证据

工作记忆与认知灵活性是执行功能的两个核心成分,但两者之间的关系并不清晰。本研究在一个数字大小交替比较任务中操纵工作记忆负荷,考察转换代价在不同记忆负荷下的差异。结果显示与非转换条件相比,转换条件下的反应时更长,正确率更低。另外,高记忆负荷下的转换代价显著高于低记忆负荷下的转换代价。这些结果表明工作记忆负荷越大,转换越难,代价越大。     

Some effort for some: further evidence that scalar implicatures are effortful

Under the assumption of the principle of cooperation (Grice, 1989), a statement such as "some eels are fish" is thought to be false since it contains less information than is considered sufficient. However, the statement is logically sound since the meaning of "some" is compatible with "all". Currently, the primary interpretation of such underinformative statements remains subject to debate. According to Levinson (2000), the pragmatic "some but not all" interpretation is the default interpretation, while others (e.g., Sperber & Wilson, 1995) argue that this pragmatic interpretation only comes to the fore when relevant within the context and is thus considered secondary to the logical "some and perhaps all" interpretation. In this study, three factors that may influence the answer pattern are studied: task load, working memory capacity, and repetition of the statements. In Experiment 1, we used a secondary task paradigm to manipulate the cognitive load under which a number of underinformative statements had to be judged. We observed that for participants with a rather limited working memory span it is harder to reach a pragmatic interpretation under cognitive load. In Experiment 2, we manipulated the repetition of the statements. We observed that with a higher number of filler statements, participants produced fewer consistent answer patterns. This study provides further evidence against the automaticity of the pragmatic interpretation: It shows that the pragmatic interpretation requires more cognitive effort than the logical interpretation and that increasing the number of filler statements inhibits the development of a response strategy.     

The role of working memory in decoding emotions

Decoding facial expressions of emotion is an important aspect of social communication that is often impaired following psychiatric or neurological illness. However, little is known of the cognitive components involved in perceiving emotional expressions. Three dual task studies explored the role of verbal working memory in decoding emotions. Concurrent working memory load substantially interfered with choosing which emotional label described a facial expression (Experiment 1). A key factor in the magnitude of interference was the number of emotion labels from which to choose (Experiment 2). In contrast the ability to decide that two faces represented the same emotion in a discrimination task was relatively unaffected by concurrent working memory load (Experiment 3). Different methods of assessing emotion perception make substantially different demands on working memory. Implications for clinical disorders which affect both working memory and emotion perception are considered.     

空间工作记忆负载对真实场景情境提示效应的影响

重复的画面布局能够促进观察者对目标项的搜索 (情境提示效应)。本研究采用双任务范式,分别在视觉搜索任务的学习阶段 (实验2a) 和测验阶段 (实验2b) 加入空间工作记忆任务, 并与单任务基线 (实验1)进行比较, 考察空间工作记忆负载对真实场景搜索中情境线索学习和情境提示效应表达的影响。结果发现: 空间负载会增大学习阶段的情境提示效应量, 同时削弱测验阶段的情境提示效应量, 而不影响情境线索的外显提取。由此可见, 真实场景中情境线索的学习和提示效应的表达均会受到有限的工作记忆资源的影响, 但情境线索提取的外显性不变。     

What you say matters: Exploring visual–verbal interactions in visual working memory

The aim of this study was to explore whether the content of a simple concurrent verbal load task determines the extent of its interference on memory for coloured shapes. The task consisted of remembering four visual items while repeating aloud a pair of words that varied in terms of imageability and relatedness to the task set. At test, a cue appeared that was either the colour or the shape of one of the previously seen objects, with participants required to select the object's other feature from a visual array. During encoding and retention, there were four verbal load conditions: (a) a related, shape–colour pair (from outside the experimental set, i.e., “pink square”); (b) a pair of unrelated but visually imageable, concrete, words (i.e., “big elephant”); (c) a pair of unrelated and abstract words (i.e., “critical event”); and (d) no verbal load. Results showed differential effects of these verbal load conditions. In particular, imageable words (concrete and related conditions) interfered to a greater degree than abstract words. Possible implications for how visual working memory interacts with verbal memory and long-term memory are discussed.     

大学生智能手机成瘾与抑制控制能力的关系:手机位置和认知负荷的调节作用

本研究以66名大学生为被试,采用Flanker效应和工作记忆的双任务设计来探讨手机位置、认知负荷在智能手机成瘾与抑制控制能力之间的调节作用。结果发现：（1）在低认知负荷下,无论是否智能手机成瘾,手机存在视线之外比手机在视线之内时抑制控制能力更差;（2）在高认知负荷下,智能手机成瘾与手机位置交互作用显著：当手机在视线之内时,智能手机成瘾者的抑制控制能力显著差于非成瘾者;而当手机在视线之外时,两者没有显著差异。结果表明,智能手机成瘾大学生的抑制控制能力不仅会受到手机位置的影响,还会受到任务本身所带来的认知负荷的调节。     

Simultaneous motor demands affect decision making under objective risk

Previous studies on factors influencing decision making focused on the effects of additional cognitive load, stress, psychological disorders, and the process of aging. The potential effects of simultaneously performing motor demands have been neglected, so far. However, previous motor / cognitive dual-task studies provide evidence for both negative as well as facilitating effects of simultaneously performing cognitive and motor tasks. The study at hand, aimed to investigate the effects of decision making under objective risk while performing additional motor demands. Seventy-two participants ranging from 18 to 30 years performed the Game of Dice Task either while sitting or while standing on one leg. Participants were asked to put similar effort on the decision task and the motor demand. The results revealed a significant main effect for “choice”, as well as a significant interaction of “choice”?×?“group”. Participants standing on one leg more frequently selected the most disadvantageous choice (one single number), whereas the “sitting group” most often selected the advantageous combination of four numbers. The findings are discussed under the aspects of executive functions, working memory, stress, somatic markers and the dual-process theory.     

Prospective memory and aging: The effects of working memory and prospective memory task load

Abstract

A person's level of engagement in other actions may influence whether a prospective action is correctly performed. This study used a computerized prospective memory task in which participants remembered to perform an action when a specified background pattern appeared while they simultaneously performed a verbal working memory task. Amount of engagement in the working memory task was manipulated by increasing the number of words to be recalled. Prospective memory load was manipulated by varying the number of prospective targets. Older adults performed more poorly than younger adults on the prospective memory task under higher working memory load and also higher prospective load. Participants with lower working memory load performed better on the prospective task, regardless of age. There were no significant age differences in the absolute accuracy of performance postdictions (post experiment performance awareness). Age differences were also found with a second prospective memory task in which participants were told to write the day of the week (DOW) on the top of answer sheets for tasks performed later in the experiment. No significant correlations were observed between the two prospective memory tasks for either age group.     

Developmental differences in prefrontal activation during working memory maintenance and manipulation for different memory loads

The ability to keep information active in working memory is one of the cornerstones of cognitive development. Prior studies have demonstrated that regions which are important for working memory performance in adults, such as dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex (VLPFC), and superior parietal cortex, become increasingly engaged across school-aged development. The primary goal of the present functional MRI study was to investigate the involvement of these regions in the development of working memory manipulation relative to maintenance functions under different loads. We measured activation in DLPFC, VLPFC, and superior parietal cortex during the delay period of a verbal working memory task in 11-13-year-old children and young adults. We found evidence for age-related behavioral improvements in working memory and functional changes within DLPFC and VLPFC activation patterns. Although activation profiles of DLPFC and VLPFC were similar, group differences were most pronounced for right DLPFC. Consistent with prior studies, right DLPFC showed an interaction between age and condition (i.e. manipulation versus maintenance), specifically at the lower loads. This interaction was characterized by increased activation for manipulation relative to maintenance trials in adults compared to children. In contrast, we did not observe a significant age-dependent load sensitivity. These results suggest that age-related differences in the right DLPFC are specific to working memory manipulation and are not related to task difficulty and/or differences in short-term memory capacity.