Detection of changes in spatial position: Short-term visual memory or motion perception?

The limiting conditions for short-term visual memory were explored for materials which are not readily codable. Two fields of random dots were presented successively in time. On half of the observations, the second display was identical to the first, and on the other half, a fraction of the dots was displaced relative to the first display. The task of the S was to indicate if any of the dots had moved (displacement detection), and in separate tests, if any of the dots had not moved (stationarity detection). Stationarity and displacement detection are largely related to the same variables, although performance is somewhat better with displacement detection. Discrimination of small displacements is critically dependent upon the interval between displays, with maximum accuracy in the region of 64 msec for briefly presented displays. Maximum accuracy is obtained under conditions which yield good apparent motion. By contrast, displacement discrimination is, within limits, relatively independent of the number of dots displayed, of the fraction of displaced dots.     

Character changes in epilepsy?]

There are no personality structures which are typical of epilepsies in the sense of a change in character that can be seen in cross and especially in longitudinal sections. Reported changes of character due to epilepsies cannot be exactly defined reproducibly for the forms of fits to be differentiated and cannot, therefore, be used operationally. There is no doubt, however, that several causal factors must be considered to be responsible for the manifestation of certain frequently observed peculiarities and characteristics, respectively. In addition to organic, psychodynamic, and socio-situational causes, long-time antiepileptic medication is an essential factor of changes in character due to diseases characterized by fits. A better understanding has now been obtained of the importance of this particular factor, and this allows to conclude that there can only be epileptic functioning and reacting.     

Are age-related changes in cognitive function driven by age-related changes in sensory processing?

Although there has been keen interest in the association among measures of sensory function and cognitive function for many years, in general, measures of sensory function have been confined to one or two senses and measures of threshold sensitivity (acuity). In this study, rigorous psychophysical measures of threshold sensitivity, temporal gap detection, temporal order identification, and temporal masking have been obtained, in hearing, vision, and touch. In addition, all subjects completed 15 subtests of the Wechsler Adult Intelligence Scale, 3rd edition (WAIS–III). Data were obtained from 245 adults (18–87 years old) for the WAIS–III and for 40 measures of threshold sensitivity and temporal processing. The focus in this report is on individual differences in performance for the entire data set. Principal-components (PC) factor analysis reduced the 40 psychophysical measures to eight correlated factors, which were reduced further to a single global sensory processing factor. Similarly, PC factor analysis of the 15 WAIS–III scores resulted in three correlated factors that were further reduced to a single global cognitive function factor. Age, global sensory processing, and global cognitive function were all moderately and significantly correlated with one another. However, paired partial correlations, controlling for the third of these three measures, revealed that the moderate correlation between age and global cognitive function went to zero when global sensory processing was controlled for; the other two partial correlations remained intact. Structural models confirmed this result. These analyses suggest that the long-standing observation of age-related changes in cognitive function may be mediated by age-related changes in global sensory processing.     

Can longitudinal changes in processing speed explain longitudinal age changes in fluid intelligence?

The processing-speed theory of cognitive aging contends tha age-related declines in intellectual function reflect the consequences of age-related slowing of processing speed. Cross-sectional data support this assumption. The association between 4-year changes in processing speed and 4-year changes in fluid intelligence was examined with a sample of 417 older adults. Changes in processing speed correlated .53 with changes in fluid intelligence. The difference in the explanatory power of processing speed regarding age-related differences and age-related changes is discussed with reference to other longitudinal studies and methodological considerations.     

Is overgeneral autobiographical memory an isolated memory phenomenon in major depression?

The present study explored the relation between overgeneral autobiographical memory (AM) and other aspects of memory functioning in depression. A total of 26 patients with major depressive disorder completed a set of memory tasks measuring AM specificity (AMT; Williams & Broadbent, 1986), working memory, semantic memory, verbal learning, delayed verbal recall, recognition memory, and source memory. Reduced specificity of AM was related to poor working memory (central executive functioning) and poor source memory. The former finding conforms to the idea that the voluntary retrieval of specific autobiographical memories (AMs) involves central executive processes (e.g., Conway & Pleydell-Pearce, 2000 Conway, M. A. and Pleydell-Pearce, C. W. 2000. The construction of autobiographical memories in the self-memory system. Psychological Review, 107: 261–288. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). The latter finding replicates and extends recent findings suggesting that overgeneral AM is part of a broader memory deficit in retrieving the specific details of the context in which information was acquired (Ramponi, Barnard, & Nimmo-Smith, 2004 Raes , F. , Hermans , D. , Williams , J. M. G. , Demyttenaere , K. , Sabbe , B. , Pieters , G . & Eelen , P. ( 2004 ). Reduced specificity of autobiographical memory: A mediator between rumination and ineffective social problem solving in major depression? Journal of affective disorders , 87 , 331 – 335  [Google Scholar]). Furthermore, in line with Ramponi et al. (2004 Raes , F. , Hermans , D. , Williams , J. M. G. , Demyttenaere , K. , Sabbe , B. , Pieters , G . & Eelen , P. ( 2004 ). Reduced specificity of autobiographical memory: A mediator between rumination and ineffective social problem solving in major depression? Journal of affective disorders , 87 , 331 – 335  [Google Scholar]), rumination was found to be related to both overgeneral AM and poor source memory.     

Fill‐in and infill errors in order memory

Many current models of memory are specified with enough detail to make predictions about patterns of errors in memory tasks. However, there are often not enough empirical data available to test these predictions. We report two experiments that examine the relative frequency of fill‐in and infill errors. In immediate serial recall tasks, subjects sometimes incorrectly recall item N too soon, placing it in position N?1. The error of interest is which item is recalled after this initial mistake. A fill‐in error is the tendency to recall item N?1 next, whereas an infill error is the tendency to recall item N+1 next. Both experiments reveal more fill‐in than infill errors, not only overall but at each possible error location throughout the list. The overall ratio is approximately 2:1. We conclude that none of the currently existing models adequately accounts for fill‐in and infill errors.     

Is overgeneral autobiographical memory an isolated memory phenomenon in major depression?

The present study explored the relation between overgeneral autobiographical memory (AM) and other aspects of memory functioning in depression. A total of 26 patients with major depressive disorder completed a set of memory tasks measuring AM specificity (AMT; Williams & Broadbent, 1986), working memory, semantic memory, verbal learning, delayed verbal recall, recognition memory, and source memory. Reduced specificity of AM was related to poor working memory (central executive functioning) and poor source memory. The former finding conforms to the idea that the voluntary retrieval of specific autobiographical memories (AMs) involves central executive processes (e.g., Conway & Pleydell-Pearce, 2000). The latter finding replicates and extends recent findings suggesting that overgeneral AM is part of a broader memory deficit in retrieving the specific details of the context in which information was acquired (Ramponi, Barnard, & Nimmo-Smith, 2004). Furthermore, in line with Ramponi et al. (2004), rumination was found to be related to both overgeneral AM and poor source memory.     

Behavioral contrast in short term memory: Serial binary memory models or parallel continuous memory models?

This paper develops a model wherein STM primacy as well as recency effects can occur. The STM primacy effects can be used to generate correct immediate recall of short lists that have not been coded in LTM. The properties of the model are interpreted in terms of explicit neural mechanisms. The STM primacy effect is a behavioral contrast effect that is analogous to the behavioral contrast that can occur during discrimination learning. The adaptational mechanism that accounts for these effects is also implicated in data on reaction time, retinal adaptation, ratio scales in choice behavior, and von Restorff-type effects. Its ubiquitous appearance is due to the fact that it solves a universal problem concerning the parallel processing of patterned data by noisy cells with finitely many excitable sites. It is argued that the STM primacy effect is not measured in interference experiments because it is masked by competitive STM interactions. These competitive interactions do not prevent the LTM primacy effect from influencing performance. The paper criticizes recent models of STM that use computer analogies to justify binary codes, serial STM buffers, and serial scanning procedures. Several deficiencies of serial models in dealing with psychological and neural processing are overcome by a model in which continuous STM activities and parallel real-time operations play an important role.     

Stimulus–response translation in manual and vocal modality: Is age‐related slowing influenced by changes in working memory functioning?

In some conditions, age‐related slowing rates are higher for manual than for vocal responses. The interaction between age and response modality was examined in four experiments in which the performance of younger (M = 22.6 years) and older (M = 70.8 years) adults was compared under various stimulus–response mapping rules. The interaction effect was not observed in a simple localisation task on which the manual modality had an advantage in both age groups (Experiment 1). When congruence between stimulus and response was reduced (Experiment 2), manual responses were disproportionately slowed in older participants. In conceptual and size comparison tasks (Experiment 3), the age‐by‐modality effect was not influenced by working memory load during the interval between the first and the second stimulus presentation. In an identification task, age‐related slowing effects were less when responses were spoken names than when nonwords were used as labels (Experiment 4). These results indicate that older participants experience a specific difficulty in activating arbitrary S–R mapping rules during executive control.     

Serial-position effects in infants’ recognition memory

Preverbal infants (7 months of age) were repeatedly shown a fixed series of photographs of adult female faces. The effects of the order of presentation of a photo (first, middle, or last) and the duration of retention (5 sec, 1 rain, or 5 rain) were subsequently assessed in a probe-recognition test. Both primacy and recency effects were obtained, but there was no evidence of recognition of the face that appeared in the middle of the series. There was also no evidence of recognition of the most recently studied face following the 5-rain retention interval. The bowed serial-position function and labile recency effect match those found in the performance of older subjects in classical verbal learning tasks, and we suggest an automatic process underlying these effects. Our explanation emphasizes differential learning and the context of the items to be remembered.     

How are pictures registered in memory?

Three experiments tested the hypothesis that pictorial memory is much less dependent on rehearsal than is verbal memory. Experiment I examined incidental learning since this is assumed to reflect learning with little or no rehearsal. Following a classification task, intentional and incidental learning for pictures and for words was compared. The superiority of pictorial memory was especially marked in incidental learning. Experiment II showed that this result was not due to differences in the amount of processing required to classify pictures and words. RTs to classify words and pictures did not differ, and incidental learning was again superior for pictures. In Experiment III rehearsal opportunity was restricted by a concurrent task during presentation of word and picture lists, and the decrement was very much greater for word learning than for picture learning. It was concluded that manipulation of rehearsal opportunity has relatively little effect on pictorial memory.     

Destination memory in social interaction: better memory for older than for younger destinations in normal aging?

Destination memory, a memory component allowing the attribution of information to its appropriate receiver (e.g., to whom did I lend my pen?), is compromised in normal aging. The present paper investigated whether older adults might show better memory for older destinations than for younger destinations. This hypothesis is based on empirical research showing better memory for older faces than for younger faces in older adults. Forty-one older adults and 44 younger adults were asked to tell proverbs to older and younger destinations (i.e., coloured faces). On a later recognition test, participants had to decide whether they had previously told some proverb to an older/younger destination or not. Prior to this task, participants reported their frequency of contact with other-age groups. The results showed lower destination memory in older adults than in younger adults. Interestingly, older adults displayed better memory for older than for younger destinations. The opposite pattern was seen in younger adults. The low memory for younger destinations, as observed in older adults, was significantly correlated with limited exposure to younger individuals. These findings suggest that for older adults, the social experience can play a crucial role in the destination memory, at least as far as exposure to other-age groups is concerned.     

Keeping an eye on the truth? Pupil size changes associated with recognition memory

During recognition memory tests participants' pupils dilate more when they view old items compared to novel items. We sought to replicate this "pupil old/new effect" and to determine its relationship to participants' responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia, and instructions to report all items as new. Participants' pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.     

Do objects in working memory compete with objects in perception?

It is generally assumed that “perceptual object” is the basic unit for processing visual information and that only a small number of objects can be either perceptually selected or encoded in working memory (WM) at one time. This raises the question whether the same resource is used when objects are selected and tracked as when they are held in WM. In two experiments, we measured dual-task interference between a memory task and a Multiple Object Tracking task. The WM tasks involve explicit, implicit, or no spatial processing. Our results suggest there is no resource competition between working memory and perceptual selection except when the WM task requires encoding spatial properties.     

Keeping an eye on the truth? Pupil size changes associated with recognition memory

During recognition memory tests participants' pupils dilate more when they view old items compared to novel items. We sought to replicate this “pupil old/new effect” and to determine its relationship to participants' responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia, and instructions to report all items as new. Participants' pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.     

What constitutes an episode in episodic memory?

The idea of episodic memory implies the existence of a process that segments experience into episodes so that they can be stored in memory. It is therefore surprising that the link between event segmentation and the organization of experiences into episodes in memory has not been addressed. We found that after participants read narratives containing temporal event boundaries at varying locations in the narrative, their long-term associative memory for information across event boundaries was lower than their memory for information within an event. This suggests that event segmentation during encoding resulted in segmentation of those same events in memory. Further, functional imaging data revealed that, across participants, brain activity consistent with the ongoing integration of information within events correlated with this pattern of mnemonic segmentation. These data are the first to address the mechanisms that support the organization of experiences into episodes in long-term memory.     

Age-related changes in materialism in adults – A self-uncertainty perspective

Materialism is the focus of much research due to its negative consequences for individuals and societies. While recent research indicates that the strength of materialistic value orientations changes with age during adulthood, little is known about the processes that cause these age-related changes. We propose that changes in materialism, as people grow older, are rooted in changes in self-uncertainty. We find evidence for this idea in two studies and across different measures of self-uncertainty. In addition, we show that the changes in materialism cannot be explained by (age-related) differences in socio-demographic variables. Finally, our results indicate that changes in self-uncertainty provide a better account for changes in materialism than age-related changes in self-esteem.     

Complexity factors in visuo‐spatial working memory

Three experiments are presented that use a technique of selective interference—irrelevant pictures—to develop our understanding of visuo‐spatial working memory. Visual noise fields are used as the irrelevant pictures. Using two related measures of simple visual complexity, the experiments demonstrate that the greater the complexity the greater the degree of interference, even within a paradigm where subjects are instructed to look at but otherwise ignore the irrelevant pictures. Both the number of dots and the density of the dots comprising the visual noise fields affect the degree of interference in a concurrent memory task. In addition, increasing the size of the field increases the amount of interference. It is argued that the results give insight into the properties of visual working memory and contribute to its theoretical development. For example, it is argued that the store is directly accessible by externally presented interference and that particular aspects of the noise displays cause interference with visual memory.