Measuring episodic memory: A novel approach with an indefinite number of alternative forms

Both clinical practice and clinical research settings can require successive administrations of a memory test, particularly when following the trajectory of suspected memory decline in older adults. However, relatively few verbal episodic memory tests have alternative forms. We set out to create a broad‐based memory test to allow for the use of an essentially unlimited number of alternative forms. Four tasks for inclusion in such a test were developed. These tasks varied the requirement for recall as opposed to recognition, the need to form an association between unrelated words, and the need to discriminate the most recent list from earlier lists, all of which proved useful. A total of 115 participants completed the battery of tests and were used to show that the test could differentiate between older and younger adults; a sub‐sample of 73 participants completed alternative forms of the tests to determine test–retest reliability and the amount of learning to learn. Copyright © 2009 John Wiley & Sons, Ltd.     

Attention and its coupling to action

We discuss two commentaries that we have received on our target article (Humphreys et al., 2010). We elaborate on the evidence for action effects on extinction and discuss whether these effects occur pre or post the selection of a response. In addition, we discuss the neural basis of the effects of action relations on extinction and on the generalization of results on action relations to real‐world examples.     

Sensory-specific satiety is intact in amnesics who eat multiple meals

What is the relationship between memory and appetite? We explored this question by examining preferences for recently consumed food in patients with amnesia. Although the patients were unable to remember having eaten, and were inclined to eat multiple meals, we found that sensory-specific satiety was intact in these patients. The data suggest that sensory-specific satiety can occur in the absence of explicit memory for having eaten and that impaired sensory-specific satiety does not underlie the phenomenon of multiple-meal eating in amnesia. Overeating in amnesia may be due to disruption of learned control by physiological aftereffects of a recent meal or to problems utilizing internal cues relating to nutritional state.     

Task effects on tactile temporal order judgments: when space does and does not matter

The ability to report the temporal order of 2 tactile stimuli (1 applied to each hand) has been shown to decline when the arms are crossed over compared with when they are uncrossed. However, these effects have only been measured when temporal order was reported by stimulus location. It is unknown whether this spatial manipulation of the body affects all tactile temporal order judgments (TOJs) or only those judgments that are spatially defined. The authors examined the effect of crossing the arms on tactile TOJs when stimuli were identified by either spatial (location) or nonspatial (frequency or duration) attributes. Spatial TOJs were significantly impaired when the arms were in crossed compared with uncrossed postures, but there was no effect of posture when order was judged by nonspatial attributes. Task-dependent modulation of the effects of posture was also evident when response complexity was reduced to go/no-go responses. These results suggest that crossing the arms impairs tactile localization and thus spatial TOJs. However, the data also suggest that localization is not a necessary precursor when temporal order can be computed by nonspatial means.     

A neural marker of content-specific active ignoring

The ability to attend to relevant events and to ignore irrelevant stimuli is crucial to survival. Theories disagree on whether this ability is dependent solely on increased neural activation for relevant items or whether active ignoring can also play a role. The authors examined the active ignoring of stimuli using a preview search procedure, where irrelevant faces appeared prior to relevant house stimuli. They found increased activation in brain regions associated with spatial memory and in content-specific face-processing areas when participants ignored the irrelevant faces. Differences arose even on trials when only previewed faces appeared, and the magnitude of these differences predicted how well faces were ignored in search. Activation associated with active ignoring decreased when a secondary task was imposed during the preview. The data reveal a neural marker for the process of actively ignoring the content and locations of irrelevant stimuli.     

视知觉组织在整体知觉中的作用--脑损伤病人的实验研究

本实验研究大脑损伤如何影响复合图形的整体知觉。三例病人脑损伤部位分别在大脑枕区、顶区、颞区、额区及基底节和豆状核。复合图形被呈现给病人和正常对照被试。强迫选择识别等任务表明,当空间相邻性决定局部图形的知觉组织时,病人识别整体性质的正确率高于(ZD和FL)或略底于(GK)识别局部性质的正确率;当形状相似性决定局部图形的知觉组织时,病人识别整体性质的正确率显著降低,而识别局部性质的正确率受到的影响较小。在同样的任务中正常被试识别整体和局部性质的正确率受知觉组织因素的影响很小。这些结果提示大脑损伤对整体知觉的破坏可能主要通过影响基于形状相似性的知觉组织实现。     

Causal Binding of Actions to Their Effects

ABSTRACT— According to widely held views in cognitive science harking back to David Hume, causality cannot be perceived directly, but instead is inferred from patterns of sensory experience, and the quality of these inferences is determined by perceivable quantities such as contingency and contiguity. We report results that suggest a reversal of Hume's conjecture: People's sense of time is warped by the experience of causality. In a stimulus-anticipation task, participants' response behavior reflected a shortened experience of time in the case of target stimuli participants themselves had generated, relative to equidistant, equally predictable stimuli they had not caused. These findings suggest that causality in the mind leads to temporal binding of cause and effect, and extend and generalize beyond earlier claims of intentional binding between action and outcome.     

Semantically induced distortions of visual awareness in a patient with Balint’s syndrome

We present data indicating that visual awareness for a basic perceptual feature (colour) can be influenced by the relation between the feature and the semantic properties of the stimulus. We examined semantic interference from the meaning of a colour word (‘‘RED”) on simple colour (ink related) detection responses in a patient with simultagnosia due to bilateral parietal lesions. We found that colour detection was influenced by the congruency between the meaning of the word and the relevant ink colour, with impaired performance when the word and the colour mismatched (on incongruent trials). This result held even when remote associations between meaning and colour were used (i.e. the word ‘‘PEA” influenced detection of the ink colour red). The results are consistent with a late locus of conscious visual experience that is derived at post-semantic levels. The implications for the understanding of the role of parietal cortex in object binding and visual awareness are discussed.     

Characteristics of 12th-grade students seriously deficient in spatial ability

When spatial ability was regressed on a measure of general intelligence in a large national sample of 12th-graders, there was a distinct downturn in the regression line at about -2 SD units. A bimodal distribution of spatial ability was found among these low scoring students, suggesting 2 qualitatively different types of individuals. Relative to students of expected spatial ability, those below expected in spatial ability were high on verbal skills and low on performance skills. Students unexpectedly low in spatial ability performed relatively well on cognitive tests that required answering unambiguous questions by retrieving information directly from long term memory, whereas they performed relatively poorly on tests requiring inference and perception of relations among novel stimuli. Students unexpectedly low in spatial ability performed especially poorly at tests involving visual-spatial perception skills. Results were similar for both sexes. The relatively poor performance of those unexpectedly low in spatial ability does not appear to be related to health problems, personality, interest differences, or biographical data. An organic impairment possibly related to lateralization represents a reasonable causal hypothesis for these data.