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Robert H Logie

Publications and source records attributed to Robert H Logie.

13 recordsLinked to original sources
PubMed2007

Executive processes in visual and spatial working memory tasks.

Three experiments are reported, which have investigated the nature of the cognitive mechanisms that underlie performance on specific visuo-spatial working memory tasks, with the emphasis on exploring the extent of central executive involvement. Experiments 1 and 2 employed oral random digit generation as an executive task within a dual-task paradigm. The results of both experiments indicated that visuo-spatial tasks that involve sequential processing of information show more interference with random digit generation than do visuo-spatial tasks that involve simultaneous processing. The third experiment substituted oral random digit generation for executive tasks that did not involve memory for serial order (vigilance tasks adapted from Vandierendonck, De Vooght, & Van der Goten, 1998b). The results indicated significant interference between the vigilance tasks and the sequential visuo-spatial task, but not with the simultaneous visuo-spatial task. Overall the results of the three experiments are interpreted as indicating that serial sequential visuo-spatial tasks involve executive resources to a significantly greater extent than do simultaneous visuo-spatial tasks, and that this can have implications for studies that attempt to make use of such tasks to fractionate separable visual and spatial components within working memory.

Adolescent↗
PubMed2006

The selective disruption of spatial working memory by eye movements.

In the late 1970s/early 1980s, Baddeley and colleagues conducted a series of experiments investigating the role of eye movements in visual working memory. Although only described briefly in a book, these studies have influenced a remarkable number of empirical and theoretical developments in fields ranging from experimental psychology to human neuropsychology to nonhuman primate electrophysiology. This paper presents, in full detail, three critical studies from this series, together with a recently performed study that includes a level of eye movement measurement and control that was not available for the older studies. Together, the results demonstrate several facts about the sensitivity of visuospatial working memory to eye movements. First, it is eye movement control, not movement per se, that produces the disruptive effects. Second, these effects are limited to working memory for locations and do not generalize to visual working memory for shapes. Third, they can be isolated to the storage/maintenance components of working memory (e.g., to the delay period of the delayed-recognition task). These facts have important implications for models of visual working memory.

Adolescent↗
PubMed2006

Visuospatial working memory and the processing of spatial descriptions.

The dual-task paradigm was used to determine whether the spatial, visual and verbal components of working memory are engaged in the processing of spatial descriptions. Participants listened to route or survey descriptions of urban-like spatial environments and then drew corresponding maps. The position of each new landmark was described either in terms of the direction to move toward this landmark (route descriptions) or its relative location with regard to the previously mentioned landmark (survey descriptions). Route and survey descriptions resulted in similar recall performance in the absence of an interfering task and landmarks were consistently less well recalled than their associated moves/locations. The pattern of interference resulting from the secondary tasks indicated that the processing of landmarks called upon both the visual and spatial components of working memory in the route perspective, whereas the processing of moves/locations essentially relied on the spatial component in both the route and the survey perspectives. The verbal component of working memory was only involved in the processing of landmarks in the survey perspective. The results suggest that distinct cognitive processes support memory for route and survey descriptions, and that distinct working memory resources support the processing of landmarks and landmark positions.

Adult↗
PubMed2005

The impact of secondary tasks on multi-tasking in a virtual environment.

One experiment is described that examined the possible involvement of working memory in the Virtual Errands Test (McGeorge et al. (2001). Using virtual environments in the assessment of executive dysfunction. Presence, 10, 375-383), which requires participants to complete errands within a virtual environment, presented on a computer screen. Time was limited, therefore participants had to swap between tasks (multi-task) efficiently to complete the errands. Forty-two undergraduates participated, all attempting the test twice. On one of these occasions they were asked to perform a concurrent task throughout (order of single and dual-task conditions was counterbalanced). The type of secondary task was manipulated between groups. Twenty-one participants were asked to randomly generate months of the year aloud in the dual-task condition, while another 21 were asked to suppress articulation by repeating the word "December". An overall dual-task effect on the Virtual Errands Test was observed, although this was qualified by an interaction with the order of single and dual-task conditions. Analysis of the secondary task data showed a drop in performance (relative to baseline) under dual-task conditions, and that drop was greater for the random generation group than the articulatory suppression group. These data are interpreted as suggesting that the central executive and phonological loop components of working memory are implicated in this test of multi-tasking.

Adolescent↗
PubMed2005

A comparison of graphical and textual presentations of time series data to support medical decision making in the neonatal intensive care unit.

OBJECTIVE: To compare expert-generated textual summaries of physiological data with trend graphs, in terms of their ability to support neonatal Intensive Care Unit (ICU) staff in making decisions when presented with medical scenarios. METHODS: Forty neonatal ICU staff were recruited for the experiment, eight from each of five groups--junior, intermediate and senior nurses, junior and senior doctors. The participants were presented with medical scenarios on a computer screen, and asked to choose from a list of 18 possible actions those they thought were appropriate. Half of the scenarios were presented as trend graphs, while the other half were presented as passages of text. The textual summaries had been generated by two human experts and were intended to describe the physiological state of the patient over a short period of time (around 40 minutes) but not to interpret it. RESULTS: In terms of the content of responses there was a clear advantage for the Text condition, with participants tending to choose more of the appropriate actions when the information was presented as text rather than as graphs. In terms of the speed of response there was no difference between the Graphs and Text conditions. There was no significant difference between the staff groups in terms of speed or content of responses. In contrast to the objective measures of performance, the majority of participants reported a subjective preference for the Graphs condition. CONCLUSIONS: In this experimental task, participants performed better when presented with a textual summary of the medical scenario than when it was presented as a set of trend graphs. If the necessary algorithms could be developed that would allow computers automatically to generate descriptive summaries of physiological data, this could potentially be a useful feature of decision support tools in the intensive care unit.

Computer Graphics↗
PubMed2004

Resistance to the impact of interruptions during multitasking by healthy adults and dysexecutive patients.

Two experiments (one with healthy adult volunteers and the other with controls and dysexecutive patients) assessed the impact of interruptions on a novel test of multitasking. The test involved switching repeatedly between four tasks (block construction, bead threading, paper folding, alphabetical searching) over a 10 min period. In Experiment 1, there were four groups of 20 healthy participants. One group attempted multitasking with no interruption, a second group was interrupted early in the test, a third group late in the test and a fourth group was interrupted both early and late. Interruption involved carrying out a fifth, unexpected task for a period of 1 min before returning to the four main tasks. There was no difference in multitasking performance between the groups. In Experiment 2 the participants were seven dysexecutive patients and 14 age-matched controls. A repeated measures approach was employed to assess the impact of two interruptions (early and late) for both groups. Contrary to predictions, the patients as well as controls were resistant to the effects of interruptions, despite their clearly impaired multitasking performance. These results suggest that the ability to deal with interruptions may be separable from the ability to organise and execute multiple tasks within a limited time frame.

Adult↗
PubMed2004

Preserved visuo-spatial transformations in representational neglect.

Patients with representational unilateral neglect were impaired in immediate recall of novel material on the neglected side as presented (viewed and removed or verbally described) or following mental rotation. Transforming material from the neglected (left) side to the non-neglected (right) side resulted in no additional loss; patients were unimpaired in directing attention to the neglected side of their representation in order to perform the mental rotation. These findings cannot be explained by the widely adopted attention deficit hypothesis for representational neglect. It is suggested that the disorder arises from damage to temporary storage functions of visuo-spatial working memory.

Adult↗
PubMed2004

Is there a specific executive capacity for dual task coordination? Evidence from Alzheimer's disease.

Three experiments compared groups of Alzheimer's disease (AD) patients and healthy older and younger participants on visuospatial tracking and digit sequence recall, as single tasks and performed concurrently. In Experiment 1, tasks were performed concurrently with very low demand relative to span. Only the AD patients showed a dual task deficit. In Experiment 2, single task demand was manipulated on each task from below span to above span for each individual. All groups showed the same performance reductions with increasing demand. In Experiment 3, demand on 1 task was constant, whereas demand on the concurrent task was varied. AD patients showed a clear dual task deficit but were no more sensitive than control groups to varying demand. Results suggest an identifiable cognitive resource for dual task coordination within a multiple component working memory system.

Adult↗
PubMed2003

Brain activation and the phonological loop: the impact of rehearsal.

Brain activation studies offer valuable techniques for exploring human cognition to complement behavioral measures and several studies report a wide range of neuroanatomical networks activated during verbal immediate memory. Behavioral investigations have shown use of multiple cognitive strategies across and within individuals, although aggregate data appear to reflect a common cognitive function. Variation in cognitive strategies could result in aggregate activation patterns that are relatively widespread and difficult to interpret. Imaging data (fMRI) from six participants instructed to use subvocal rehearsal showed significant left hemisphere activation in the inferior parietal gyrus and inferior and middle frontal gyri, a pattern of activation more clearly focused than in previous brain activation studies of immediate verbal serial ordered recall. Our results should be relatively free of the influence of other mental operations, and emphasise the importance of considering which cognitive strategies might give rise to focused or to diverse patterns of brain activation.

Adult↗
PubMed2003

The Prospective and Retrospective Memory Questionnaire (PRMQ): Normative data and latent structure in a large non-clinical sample.

The Prospective and Retrospective Memory Questionnaire (PRMQ; Smith, Della Sala, Logie, & Maylor, 2000) was developed to provide a self-report measure of prospective and retrospective memory slips in everyday life. It consists of sixteen items, eight asking about prospective memory failures, and eight concerning retrospective failures. The PRMQ was administered to a sample of the general adult population (N = 551) ranging in age between 17 and 94. Ten competing models of the latent structure of the PRMQ were derived from theoretical and empirical sources and were tested using confirmatory factor analysis. The model with the best fit had a tripartite structure and consisted of a general memory factor (all items loaded on this factor) plus orthogonal specific factors of prospective and retrospective memory. The reliabilities (internal consistency) of the Total scale and the Prospective and Retrospective scales were acceptable: Cronbach's alpha was 0.89, 0.84, and 0.80, respectively. Age and gender did not influence PRMQ scores, thereby simplifying the presentation and interpretation of normative data. To ease interpretation of scores on the PRMQ, tables are presented for conversion of raw scores on the Total scale and Prospective and Retrospective scales to T scores (confidence limits on scores are also provided). In addition, tables are provided to allow users to assess the reliability and abnormality of differences between an individual's scores on the Prospective and Retrospective scales.

Adolescent↗
PubMed2002

Concurrent performance of two memory tasks: evidence for domain-specific working memory systems.

Previous studies of dual-task coordination in working memory have shown a lack of dual-task interference when a verbal memory task is combined with concurrent perceptuomotor tracking. Two experiments are reported in which participants were required to perform pairwise combinations of (1) a verbal memory task, a visual memory task, and perceptuomotor tracking (Experiment 1), and (2) pairwise combinations of the two memory tasks and articulatory suppression (Experiment 2). Tracking resulted in no disruption of the verbal memory preload over and above the impact of a delay in recall and showed only minimal disruption of the retention of the visual memory load. Performing an ongoing verbal memory task had virtually no impact on retention of a visual memory preload or vice versa, indicating that performing two demanding memory tasks results in little mutual interference. Experiment 2 also showed minimal disruption when the two memory tasks were combined, although verbal memory (but not visual memory) was clearly disrupted by articulatory suppression interpolated between presentation and recall. These data suggest that a multiple-component working memory model provides a better account for performance in concurrent immediate memory tasks than do theories that assume a single processing and storage system or a limited-capacity attentional system coupled with activated memory traces.

Adult↗
PubMed2002

Prospective and retrospective memory in normal aging and dementia: an experimental study.

Two experiments investigated the effects of normal aging and dementia on laboratory-based prospective memory (PM) tasks. Participants viewed a film for a later recognition memory task. In Experiment 1, they were also required either to say "animal" when an animal appeared in the film (event-based PM task) or to stop a clock every 3 min (time-based PM task). In both tasks, young participants were more successful than older participants, who were, in turn, more successful than patients with Alzheimer's disease (AD). For successful remembering in the time-based task, older participants and AD patients checked the clock more often than did young participants. In Experiment 2, participants were asked to reset a clock either when an animal appeared in the film (unrelated cue-action) or when a clock appeared in the film (related cue-action). Responses were faster in the related condition than in the unrelated condition. Again, there were differences in PM performance between young and older participants, and between older participants and AD patients. The observed deficits were not due to the forgetting of the PM task instructions in either experiment. Retrospective memory (RM) tasks (digit span, sentence span, free recall, and recognition) were more impaired by AD than were the PM tasks. Factor analysis revealed separate factors corresponding to RM and PM.

Adult↗