Search

Purpose Events (e.g., seeing a familiar face) may initiate retrieval of associated information (e.g., person’s name), but not all cue initiated memory retrieval is welcome (e.g., trauma). Memory suppression refers to the ability to halt unwanted retrieval, and any erosion of memory associations in response to repeatedly excluding a memory from consciousness. The current study sought to examine event related potential (ERP, averaged scalp electrical recordings) correlates of inhibitory cognitive control of memory retrieval and any linkage of such control to ruminative memory styles. Method Participants (N=23) first learned face-picture pairings. ERPs were then recorded as they viewed face cues while either bringing the associated picture to mind (think trial), or not allowing the associated picture to come to mind (no-think trial). Results Emotional valence of learned pictures (negative vs neutral) modulated a posterior (P1, 100-150 ms) ERP associated with attention to the face cue. Memory strategy (think vs no-think) modulated a frontal (P3, 350-450 ms) associated with alerting of the need to control retrieval. Both valence and strategy worked in combination to modulate a late posterior (LC, 450-550 ms) ERP associated with successful memory retrieval. Brooding, a negative form of rumination, was found to be positively correlated with the LC ERP. Conclusions The results suggest early separation of emotional and strategic control of retrieval, but later combined control over access to working memory. Moreover, the positive correlation of brooding and the LC suggest that individuals who are high in application of perseverative strategies to memory retrieval will show greater modulation of the retrieval-related LC ERP.

This paper focuses on viewers’ perception of the relative size of words presented in tag clouds. Tag clouds are a type of visualization that displays the contents of a document as a cluster (cloud) of key words (tags) with frequency (importance) indicated by tag word features such as size or color, with variation of size within a tag cloud being the most common indicator of tag importance. Prior studies have shown that word size is the most influential factor of tag importance and tag memory. Systematic biases in relative size perception in tag clouds are therefore likely to have important implications for viewer understanding of tag cloud visualizations. Significant under- and over-perception of the relative size of tag words were observed, depending on the relative size ratio of the target tag words compared. The qualitative change in the direction of the estimation bias was predicted by a simple power-law model for size perception. This bias in relative size perception was modulated somewhat by a change to a bold typeface, but the typeface effect varied in a complex manner with the size and location of the tags. The results provide a first report of systematic biases in relative size judgment in tag clouds, suggest that, to a first approximation, simple power-law scaling models developed for simple displays containing 1–2 objects on a blank background, may be applicable to relative size judgments in complex tag clouds. The results may provide useful design guidance for tag cloud designers.

Introduction Events (e.g., seeing a familiar face) may initiate retrieval of associated information (e.g., person's name), but not all cue‐initiated memory retrieval is welcome (e.g., trauma). Retrieval suppression refers to the ability to halt unwanted retrieval, and any erosion of memory associations in response to repeatedly excluding a memory from consciousness. The current study sought to examine event‐related potential (ERP, averaged scalp electrical recordings) correlates of inhibitory cognitive control of memory retrieval and any linkage of such control to ruminative memory styles. Methods Participants (N = 23) first learned face‐picture pairings. ERPs were then recorded as they viewed face cues while either bringing the associated picture to mind (think trial), or not allowing the associated picture to come to mind (no‐think trial). Results Emotional valence of learned pictures (negative versus neutral) modulated a posterior (P1, 100–150 ms) ERP associated with attention to the face cue. Memory strategy (think versus no‐think) modulated a frontal (P3, 350–450 ms) associated with alerting of the need to control retrieval. Both valence and strategy worked in combination to modulate a late posterior (LC, 450–550 ms) ERP associated with successful memory retrieval. Brooding, a negative form of rumination, was found to be positively correlated with the LC ERP. Conclusion The results suggest early separation of emotional and strategic control of retrieval, but later combined control over access to working memory. Moreover, the positive correlation of brooding and the LC suggest that individuals who are high in application of perseverative strategies to memory retrieval will show greater modulation of the retrieval‐related LC ERP., Most individuals are able to keep unwanted memories out of everyday consciousness to get through their daily activities. This adaptable control process helps us manage our emotional memories. However, this process may be disrupted in individuals experiencing psychiatric conditions characterized by intrusive ruminative thoughts, such as post‐traumatic stress disorder. Here, we use electroencephalography techniques to demonstrate that our participants are able to successfully learn to suppress negative stimuli. Our findings suggest that there may be potential ways to enhance retrieval suppression mechanisms for individuals with psychiatric conditions before their symptoms become debilitating.

Objectives To determine whether auditory and visual computer games yield transfer effects that (a) are modality-specific to verbal memory (auditory stimulus presentation) and visual-processing tests, (b) affect working memory and processing speed, (c) are synergistic for combined game-type play, and (d) are durable. Method A Pilot Study (N = 44) assessed visual transfer effects in a two-group pre–post design. The Main Study (N = 151) employed a 2 (visual games: yes, no) × 2 (auditory games: yes, no) × 3 (test session: pretest, post-test, follow-up) design, allowing different training groups to act as active controls for each other. Neuropsychological test scores were aggregated into verbal-memory (auditory presentation), visual-processing, working-memory, and processing-speed indexes. Results Visual-processing and working-memory pre–post-training change scores were differentially modulated across the four gameplay groups in the main sample, demonstrating transfer effects differing across both active- and passive-control groups. Visual training yielded modality-specific transfer effects in both samples, transfer to working memory in the main sample, and transfer to processing speed in the pilot sample. There were no comparable transfer effects for auditory training. Combined-visual-and-auditory training failed to yield synergistic effects or any significant transfer effects. Visual-processing transfer effects remained significant at follow-up. Discussion Visual and auditory games differentially modulated transfer effects. Domain-specific visual transfer effects were found at post-test and were durable at follow-up. Visual gameplay holds potential to ameliorate age-related cognitive decline in visual cognition.

Context Motor planning, a prerequisite for goal-driven movement, is a complex process that occurs in the cortex. Evidence has suggested that motor planning is altered in patients with chronic ankle instability (CAI). We know balance training can improve balance, but we do not know if it also improves motor planning. Such changes in cortical activity can be assessed using electroencephalography. Objective To evaluate changes in cortical measures of motor planning after balance training in patients with CAI. Design Controlled laboratory study. Setting Research laboratory. Patients or Other Participants Fifteen patients with CAI (age = 20.80 ± 2.37 years, height = 169.47 ± 7.95 cm, mass = 70.45 ± 19.25 kg). Intervention(s) A 4-week progression-based balance-training program. Main Outcome Measure(s) Motor planning was assessed via electroencephalography before a lateral-stepping task. We calculated event-related spectral perturbations in the θ (4–8 Hz), α (8–12 Hz), β (14–25 Hz), and γ (30–50 Hz) bands. The change in power (in decibels) was calculated in each band for the 500 milliseconds before the onset of the lateral-stepping movement. Additional outcomes were the Foot and Ankle Ability Measure (FAAM)–Activities of Daily Living and Sport subscales; the anterior-, posteromedial-, and posterolateral-reach directions of the Star Excursion Balance Test; and static balance. Patients completed 3 test sessions: baseline, 24- to 48-hour posttest, and 1-week posttest. Repeated-measures analyses of variance were used to assess changes over time. The α level was set at .05. Results The FAAM–Activities of Daily Living subscale score was improved at both posttests (P < .05), and the FAAM-Sport subscale score was improved at the 1-week posttest (P = .008). Balance was better in all 3 directions of the Star Excursion Balance Test at both posttest sessions (P < .001). After balance training, no differences were identified in cortical activity at either posttest session (P > .05). Conclusions No improvements were identified in electroencephalography measures of motor planning during lateral stepping in patients with CAI. Improved balance suggested that sensorimotor adaptations occurred, but they may not have transferred to the lateral-stepping task or they may have been mediated via other processes in patients with CAI.

Objectives: To evaluate the cognitive, neuropsychiatric, and quality of life outcomes of computer-based cognitive training and social interaction on people with mild to moderate dementia. Methods: Ten individuals with dementia were recruited to complete a cognitive training regimen. They were randomly assigned to a high social interaction (HSI) group (n = 5) and low social interaction (LSI) group (n = 5). Eight of the original 10 participants completed the cognitive training and were evaluated on cognitive abilities, neuropsychiatric symptoms (NPS), and quality of life (QoL). Results: Mean scores for the HSI group increased on cognitive assessments, where mean scores for the LSI group saw decline, or stability. There was an overall reduction in the frequency and severity of NPS presentation in both the HSI and LSI group. Mixed results were found for mean changes in QoL. Discussion: These results support the idea of social interaction influencing cognitive outcomes, cognitive training influencing NPS, and both social interaction and cognitive training influencing QoL. The findings illustrate the feasibility and importance of incorporating social activity to computerized cognitive training for people with dementia. Clinical Implications: Cognitive training that incorporates social interaction may be a promising intervention for individuals with dementia experiencing NPS.

Summary: We investigated how holding participants accountable for their responses affected unconscious plagiarism when solving a Boggle puzzle task (finding words in a 44 letter matrix). Both experimental and control participants (N=60) generated puzzle solutions with a computer partner, recalled their own previously generated solutions, and then produced new solutions to the puzzles. Accountability was manipulated by telling participants in the experimental group before beginning the initial-generation phase that at the end of the session, they would review their generated responses with the researcher (accountable participants). Accountable participants plagiarized less than control participants when generating words with the computer and generating new solutions on their own but not when they were attempting to recall words they initially generated. The data are discussed in terms of the leading theoretical explanation of unconscious plagiarism, the source-monitoring framework. Copyright © 2012 John Wiley & Sons, Ltd. Cases of plagiarism are of the utmost concern in academic and non-academic contexts alike (e.g. Goodwin withdraws, 2002; Plotz, 2002), but not all plagiarism is intentional. Anecdotal cases of unconscious plagiarism have been recorded in which the perpetrator was truly unaware of his crime (e.g. Freud, 1917). Cryptomnesia, or unconscious plagiarism, occurs when remembered ideas are not recognized as memories (Taylor, 1965). In other words, cryptomnesia occurs when an individual claims an idea to be her own new creation, when in fact, she fails to remember that it was produced by someone else, or even by herself at a prior point in time (Johnson, Hashtroudi, & Lindsay, 1993; Marsh & Bower, 1993; see also Goodwin, 2002). The present study tested the hypothesis that unconscious plagiarism can be reduced by simply highlighting that participants’responses will be reviewed with a knowledgeable other, in this case, with the researcher. To lay the foundation for this research, we introduce how cryptomnesia is investigated in the laboratory and discuss why this memory error arises. Then, we discuss the effect of motivation on unconscious plagiarism. Finally, we summarize the hypothesis in the present study. The first laboratory investigation of cryptomnesia was performed by Brown and Murphy (1989), and their three-stage paradigm has been utilized in many subsequent investigations of the phenomenon. In the first stage, called initial generation, participants took turns within a group of four participants generating a new exemplar from common categories such as sports and clothing. In the second stage, recall own, participants recalled the four exemplars they personally generated for each category. In the third stage, generate new, participants generated four new examples that had not been stated by the group previously. Brown and Murphy defined unconscious plagiarism as when a participant recalled another person’s category exemplar when she was instructed to remember the exemplars she stated or when a participant wrote another person’s exemplar when she was instructed to write an entirely new response. They also noted that a person can plagiarize herself when attempting to generate a new word, yet she repeats one she generated earlier. Brown and Murphy found that participants unconsciously plagiarized at levels significantly greater than chance in all three stages. Marsh and Bower (1993) adapted the Brown and Murphy paradigm, so participants generated word solutions to Boggle puzzles with a computer (located words in a 44 letter matrix). They found that this task elicited unconscious plagiarism of the computer partner and of the participants themselves. Subsequent studies indicate that cryptomnesia also occurs when stimuli to be plagiarized are more complex than single-word responses. Cryptomnesia has been docu

The present study provides a meta-analysis of cognitive rehabilitation literature (K = 115, N = 2,014) that was originally reviewed by K. D. Cicerone et al. (2000, 2005) for the purpose of providing evidence-based practice guidelines for persons with acquired brain injury. The analysis yielded a small treatment effect size (ES = .30, d(+) statistic) directly attributable to cognitive rehabilitation. A larger treatment effect (ES = .71) was found for single-group pretest to posttest outcomes; however, modest improvement was observed for nontreatment control groups as well (ES = .41). Correction for this effect, which was not attributable to cognitive treatments, resulted in the small, but significant, overall estimate. Treatment effects were moderated by cognitive domain treated, time postinjury, type of brain injury, and age. The meta-analysis revealed sufficient evidence for the effectiveness of attention training after traumatic brain injury and of language and visuospatial training for aphasia and neglect syndromes after stroke. Results provide important quantitative documentation of effective treatments, complementing recent systematic reviews. Findings also highlight gaps in the scientific evidence supporting cognitive rehabilitation, thereby indicating future research directions.

There is debate regarding the integrity of semantic memory in dementia of the Alzheimer type (DAT). One view argues that DAT is associated with a breakdown in semantic memory; the other argues that DAT is associated with predominantly preserved semantic memory and a breakdown in retrieval. The classic release from proactive interference (RPI) paradigm was used to shed light on this debate. Individuals with early-stage DAT (n = 36) and healthy older adult controls (n = 45) participated in an RPI paradigm. Each trial was a Brown–Peterson task in which participants read three-word lists, counted (for 0, 3, 6, or 9 s), and recalled the words. Both groups showed significant proactive interference (PI), but the size of the PI was significantly smaller in the DAT group. The group difference in PI may be due to the faster forgetting rate in the DAT group. Both groups showed significant RPI and there was no group difference in size when RPI was considered in terms of PI levels. Both groups showed PI and RPI in prior list intrusions. The DAT group's significant buildup and release of PI based on semantic categories suggest predominantly preserved semantic memory activity, at least, in early-stage DAT individuals. (JINS, 2003, 9, 830–838.)

Social skills and social status are important aspects of development that are likely to be influenced by an individual's ability to appropriately solve social problems. In this investigation, children (9–13 year olds) with and without mental retardation were asked to provide solutions to three types of social problems. Students were first asked to respond to open-ended questions and then were presented with three new problems in a forced-choice format. Children were also rated as liked or not liked by their same sex peers. Our findings indicated small but interesting differences between the children with and without retardation. In the open-ended benign situation (peer entry), students with mental retardation provided fewer assertive solutions and more appeal to authority solutions than their peers. In contrast, in the forced-choice hostile situation, children with mental retardation chose more assertive solutions and fewer appeal to authority than their peers. This same pattern of responses was reflected in a comparison of highly accepted children and less well-accepted children. The less accepted children chose more assertive solutions and fewer appeal to authority than their peers. It is possible that the different tendencies in the social problem solving of students with mental retardation could put them at risk for being less well accepted by their peers without mental retardation.

The J. D. Cohen, K. Dunbar, and J. L. McClelland (1990) model of Stroop task performance is used to model data from a study by D. H. Spielder, D. A. Balota, and M. E. Faust (1996). The results indicate that the model fails to capture overall differences between word reading and color naming latencies when set size is increased beyond 2 response alternatives. Further empirical evidence is presented that suggests that the influence of increasing response set size in Stroop task performance is to increase the difference between overall color naming and word reading, which is in direct opposition to the decrease produced by the Cohen et al. architecture. Although the Cohen et al. model provides a useful description of meaning-level interference effects, the qualitative differences between word reading and color naming preclude a model that uses identical architectures for each process, such as that of Cohen et al., to fully capture performance in the Stroop task.

In two experiments we investigated the extent to which individuals with dementia of the Alzheimer type (DAT) manage the activation of contextually appropriate and inappropriate meanings of ambiguous words during sentence comprehension. DAT individuals and healthy older individuals read sentences that ended in ambiguous words and then determined if a test word fit the overall meaning of the sentence. Analysis of response latencies indicated that DAT individuals were less efficient than healthy older individuals at suppressing inappropriate meanings of ambiguous words not implied by sentence context, but enhanced appropriate meanings to the same extent, if not more, than healthy older adults. DAT individuals were also more likely to allow inappropriate information to actually drive responses (i.e., increased intrusion errors). Overall, the results are consistent with a growing number of studies demonstrating impairments in inhibitory control, with relative preservation of facilitatory processes, in DAT.

Individuals with dementia of the Alzheimer type (DAT; n 53, ages 55–91), healthy older adults (n 75, ages 59 –91), and younger adults (n 24, ages 18 –24) performed a word-primed picturenaming task. Word primes were neutral (ready), semantically or phonologically related, or unrelated to the correct picture name. All groups produced equivalent unrelated-word interference and semantic priming effects in response latencies. However, analysis of errors revealed a DAT-related increase of phonological blocking. The results suggest that picture-naming errors in DAT are due, at least in part, to a breakdown in access to phonological representations of object names as a consequence of reduced inhibitory control over other highly active alternatives. Progressive impairment of lexicosemantic processing is an important aspect of one of three major aspects of cognitive processing declines associated with dementia of the Alzheimer type (DAT). Recent factor analytic results (Kanne, Balota, Storandt, McKeel, & Morris, 1998) found that, whereas individuals without DAT yielded a single undifferentiated factor on a battery of psychometric tests, the scores of a large sample of individuals with DAT yielded three global cognitive-decline factors of Cognitive Control, Memory/Lexical Processing, and Visuospatial Processing. These factors were related to the pattern of neuropathology in a subset of individuals who subsequently underwent an autopsy, indicating that regional cortical changes in frontal, temporal, and parietal cortices were related to declines in the Cognitive Control, Memory/Lexical Processing, and Visuospatial Processing factors, respectively.

To identify psychological factors involved in obesity 45 individuals (40 women and 5 men), ranging in age from 21 to 54 years ( M age = 41 yr.), who were candidates for silastic ring vertical stapled gastroplasty were assessed on the Millon Behavioral Health Inventory and the Millon Multiaxial Clinical Inventory-III. In addition, a number of demographic variables such as education, marital status, and age of onset of obesity were considered. Analysis indicated that significant predictors of weight loss at a 6-mo. postoperative assessment include age of onset of obesity and scores on the Schizoid scale of the Millon-III. These findings may be of assistance in identifying personality variables associated with changes in weight if replicated in a larger sample.

Research on group differences in response latency often has as its goal the detection of Group x Treatment interactions. However, accumulating evidence suggests that response latencies for different groups are often linearly related, leading to an increased likelihood of finding spurious overadditive interactions in which the slower group produces a larger treatment effect. The authors propose a rate-amount model that predicts linear relationships between individuals and that includes global processing parameters based on large-scale group differences in information processing. These global processing parameters may be used to linearly transform response latencies from different individuals to a common information-processing scale so that small-scale group differences in information processing may be isolated. The authors recommend linear regression and z-score transformations that may be used to augment traditional analyses of raw response latencies.

Older and young adults were tested on eight nonlexical tasks that overlapped extensively in complexity: disjunctive choice reaction time, line-length discrimination, letter classification, shape classification, mental rotation, visual search, abstract matching, and mental paper-folding. Performance on the first seven tasks was associated with equivalently low error rates in both groups, making it possible to directly compare their response times (RTs) on these tasks. Consistent with domain-specific slowing, the relationship between the RTs of the older adults and the RTs of the young adults was well described by a task-independent mathematical (Brinley) function. Evidence from this analysis and from analyses based on task-specific information-processing models leads to similar conclusions and provides converging support for general cognitive slowing in the nonlexical domain.

Publisher Summary This chapter elucidates the conception of skilled suppression. Suppression is treated as an active dampening of activation. It is proposed in this chapter that suppression differs from passive decay and that successful suppression underlies skilled comprehension. This chapter presents experiments that demonstrated that skilled comprehenders are more successful in suppressing inappropriate, incorrect, absent, or to-be-ignored information. The chapter also discusses whether the mechanism of suppression identified to underlie skilled comprehension is susceptible to probability. This chapter presents two new experiments that demonstrate that successful suppression of the contextually inappropriate meanings of ambiguous words and successful suppression of the incorrect forms of homophones are susceptible to the probability of trials on which suppression is needed. These new data suggest that the conception of suppression is mediated by the demands of the experimental context.

Publisher Summary This chapter focuses on the mechanism of suppression and the vital role that suppression plays in sentence comprehension. The chapter demonstrates how suppression fine-tunes the meanings of words and the vital role that suppression plays in sentence comprehension by documenting that less skilled readers/listeners suffer from less efficient suppression mechanisms. Less skilled readers/listeners are also less able to suppress the incorrect forms of homophones, and they are less able to suppress words while viewing pictures or suppress pictures while reading words. Anaphors differ in how much suppression and enhancement they trigger. The more explicit the anaphor, the more suppression and enhancement it triggers. The mechanisms of suppression and enhancement are also crucial to a process called cataphoric access.

In two experiments we investigated the extent to which interference from contextually inappropriate information was attenuated or suppressed over time in the two cerebral hemispheres during sentence comprehension. Subjects viewed centrally presented sentences ending in either a homophone or a homograph and made speeded judgments as to whether a laterally presented test word was related to the overall meaning of the sentence. Suppression of contextually inappropriate forms of homophones was found when test words were presented to either hemifield, but suppression of inappropriate senses of homographs was found only when test words were presented to the right visual hemifield. The results from the homograph experiment are consistent with the hypothesis that right and left hemisphere semantic selection systems operate in qualitatively different ways. The results from the homophone experiment suggest that while the left hemisphere may be more efficient at suppression, both hemispheres possess the ability to suppress inappropriate information to some degree.