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Fergus I M Craik - One of the best experts on this subject based on the ideXlab platform.
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effects of aging and Divided Attention on memory for items and their contexts
Psychology and Aging, 2010Co-Authors: Fergus I M Craik, Li Luo, Yuiko SakutaAbstract:It is commonly found that memory for context declines disproportionately with aging, arguably due to a general age-related deficit in associative memory processes. One possible mechanism for such deficits is an age-related reduction in available processing resources. In two experiments we compared the effects of aging to the effects of division of Attention in younger adults on memory for items and context. Using a technique proposed by Craik (1989), linear functions relating memory performance for items and their contexts were derived for a Young Full Attention group, a Young Divided Attention group, and an Older Adult group. Results suggested that the Old group showed an additional deficit in associative memory that was not mimicked by Divided Attention. It is speculated that both Divided Attention and aging are associated with a loss of available processing resources that may reflect inefficient frontal lobe functioning, whereas the additional age-related decrement in associative memory may reflect inefficient processing in medial-temporal regions.
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effects of bilingualism aging and semantic relatedness on memory under Divided Attention
Canadian Journal of Experimental Psychology, 2007Co-Authors: Myra A Fernandes, Fergus I M Craik, Elle Ialystok, Shary KreugeAbstract:We examined how encoding and retrieval processes were affected by manipulations of Attention, and whether the degree of semantic relatedness between words in the memory and distracting task modulated these effects. We also considered age and bilingual status as mediating factors. Monolingual and bilingual younger and older adults studied a list of words from a single semantic category pre- sented auditorily, and later free recalled them aloud. During either study or retrieval, participants concurrently per- formed a distracting task requiring size decisions to words from either the same or a different semantic category as the words in the memory task. The greatest disruptions of memory from Divided Attention (DA) were for encoding rather than retrieval. The effect of semantic relatedness was significant only for DA at encoding. Older age and bilin- gualism were associated with lower recall scores in all con- ditions, but these factors did not influence the magnitude of memory interference. The results suggest that encoding is more sensitive to semantic similarity in a distracting task than is retrieval. The role of Attention at encoding and retrieval is discussed.
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Divided Attention in younger and older adults effects of strategy and relatedness on memory performance and secondary task costs
Journal of Experimental Psychology: Learning Memory and Cognition, 2005Co-Authors: Moshe Navehbenjami, Jonatha Guez, Fergus I M Craik, Shary KreugeAbstract:Divided Attention at encoding leads to a significant decline in memory performance, whereas Divided Attention during retrieval has relatively little effect; nevertheless, retrieval carries significant secondary task costs, especially for older adults. The authors further investigated the effects of Divided Attention in younger and older adults by using a cued-recall task and by measuring retrieval accuracy, retrieval latency, and the temporal distribution of Attentional costs at encoding and retrieval. An age-related memory deficit was reduced by pair relatedness, whereas strategy instructions benefited both age groups equally. Attentional costs were greater for retrieval than for encoding, especially for older adults. These findings are interpreted in light of notions of an age-related associative deficit (M. Naveh-Benjamin, 2000) and age-related differences in the use of self-initiated activities and environmental support (F. I. M. Craik, 1983, 1986).
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the effects of aging and Divided Attention on memory for item and associative information
Psychology and Aging, 2003Co-Authors: Ala D Castel, Fergus I M CraikAbstract:The present study examined how aging and Divided Attention influence memory for item and associative information. Older adults and younger adults working under full-Attention conditions and younger adults working under Divided-Attention conditions studied unrelated word pairs. Memory for item information was measured by later recognition of the 2nd word in the pair, and associative information was measured by recognition of the entire pair. Both older adults in the full-Attention condition and younger adults in the Divided-Attention condition performed more poorly than younger adults in the full-Attention condition, with the deficit in associative information being greater than the deficit in item information. In addition, a differentially greater associative decrement was found for the older adults, as shown by their heightened tendency to make false-alarm responses to re-paired (conjunction) distractors. The results are discussed in terms of an age-related reduction in processing resources compounded by an age-related increase in older adults' reliance on familiarity in associative recognition memory.
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effects of Divided Attention on episodic memory in chronic traumatic brain injury a function of severity and strategy
Neuropsychologia, 2002Co-Authors: Jennife A Mangels, Fergus I M Craik, Ia Levine, Michael L Schwartz, Donald T StussAbstract:Eleven patients with mild traumatic brain injury (MTBI) and 13 patients with moderate-to-severe TBI (STBI) were compared to 10 matched controls on episodic memory for pictorial scene-object associations (e.g. kitchen-bread) and a range of standardized neuropsychological tests of memory and frontal-lobe functions. We tested the hypothesis that deficits in episodic memory result from impaired Attentional resources and/or strategic control by manipulating Attentional load at encoding (focused versus Divided Attention) and environmental support at retrieval (free recall and recalled cued by scene versus recognition of object and scene). Patients with TBI were disproportionately affected by the Divided Attention manipulation, but this effect was modulated by injury severity and encoding strategy. Overall, MTBI patients were impaired only when items were encoded under Divided Attention, indicating memory deficits that were secondary to deficits in the executive control. STBI patients could be differentiated into two distinct functional subgroups based on whether they favored a strategy of attending to the encoding or digit-monitoring task. The subgroup favoring the digit-monitoring task demonstrated deficits in the focused Attention condition, and disproportionate memory deficits in the Divided Attention condition. In contrast, the subgroup favoring the encoding task demonstrated intact performance across all memory measures, regardless of Attentional load, and despite remarkable similarity to the other STBI subgroup on demographic, neuropsychological, and acute injury severity measures. We discuss these outcome differences in terms of the relationship between strategy and executive control and highlight the need for more sensitive anatomical and behavioral measurement at both acute and chronic stages of injury.
P Azouvi - One of the best experts on this subject based on the ideXlab platform.
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rehabilitation of Divided Attention after severe traumatic brain injury a randomised trial
Neuropsychological Rehabilitation, 2010Co-Authors: Josette Couille, Stephane Soury, Gaelle Lebornec, Sybille Aslou, P A Joseph, J M Mazau, P AzouviAbstract:Patients with severe traumatic brain injury (TBI) frequently suffer from a difficulty in dealing with two tasks simultaneously. However, there has been little research on the rehabilitation of Divided Attention. The objective of the present study was to assess the effectiveness of a rehabilitation programme for Divided Attention after severe TBI. Twelve patients at a subacute/chronic stage after a severe TBI were included. A randomised AB vs. BA cross-over design was used. Training lasted six weeks, with four one-hour sessions per week. It was compared to a non-specific (control) cognitive training. During experimental treatment, patients were trained to perform two concurrent tasks simultaneously. Each one of the two tasks was first trained as a single task, then both tasks were given simultaneously. A progressive hierarchical order of difficulty was used, by progressively increasing task difficulty following each patient's individual improvement. Patients were randomised in two groups: one starting with dual-task training, the other with control training. Outcome measures included target dual-task measures, executive and working memory tasks, non-target tasks, and the Rating Scale of Attentional Behaviour addressing Attentional problems in everyday life. Assessment was not blind to treatment condition. A significant training-related effect was found on dual-task measures and on the Divided Attention item of the Rating Scale of Attentional Behaviour. There was only little effect on executive measures, and no significant effect on non-target measures. These results suggest that training had specific effects on Divided Attention and helped patients to deal more rapidly and more accurately with dual-task situations.
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Divided Attention and mental effort after severe traumatic brain injury
Neuropsychologia, 2004Co-Authors: P Azouvi, Josette Couille, Sybille Aslou, Michel Leclercq, Yves Marti, M RousseauAbstract:The aim of this study was to assess dual-task performance in TBI patients, under different experimental conditions, with or without explicit emphasis on one of two tasks. Results were compared with measurement of the subjective mental effort required to perform each task. Forty-three severe TBI patients at the subacute or chronic phase performed two tasks under single- and dual-task conditions: (a) random generation; (b) visual go-no go reaction time task. Three dual-task conditions were given, requiring either to consider both tasks as equally important or to focus preferentially on one of them. Patients were compared to matched controls. Subjective mental effort was rated on a visual analogic scale. TBI patients showed a disproportionate increase in reaction time in the go-no go task under the dual-task condition. However, they were just as able as controls to adapt performance to the specific instructions about the task to be emphasised. Patients reported significantly higher subjective mental effort, but the variation of mental effort according to task condition was similar to that of controls. These results suggest that the Divided Attention deficit of TBI patients is related to a reduction in available processing resources rather than an impairment of strategic processes responsible for Attentional allocation and switching. The higher level of subjective mental effort may explain why TBI patients frequently complain of mental fatigue, although this subjective complaint seems to be relatively independent of cognitive impairment.
Morris Moscovitch - One of the best experts on this subject based on the ideXlab platform.
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Divided Attention improves delayed but not immediate retrieval of a consolidated memory
PLOS ONE, 2014Co-Authors: Yoav Kessle, Gordo Winocu, Susa Vandermorris, Nigel Gopie, Alexande R Daros, Morris MoscovitchAbstract:A well-documented dissociation between memory encoding and retrieval concerns the role of Attention in the two processes. The typical finding is that Divided Attention (DA) during encoding impairs future memory, but retrieval is relatively robust to Attentional manipulations. However, memory research in the past 20 years had demonstrated that retrieval is a memory-changing process, in which the strength and availability of information are modified by various characteristics of the retrieval process. Based on this logic, several studies examined the effects of DA during retrieval (Test 1) on a future memory test (Test 2). These studies yielded inconsistent results. The present study examined the role of memory consolidation in accounting for the after-effect of DA during retrieval. Initial learning required a classification of visual stimuli, and hence involved incidental learning. Test 1 was administered 24 hours after initial learning, and therefore required retrieval of consolidated information. Test 2 was administered either immediately following Test 1 or after a 24-hour delay. Our results show that the effect of DA on Test 2 depended on this delay. DA during Test 1 did not affect performance on Test 2 when it was administered immediately, but improved performance when Test 2 was given 24-hours later. The results are consistent with other findings showing long-term benefits of retrieval difficulty. Implications for theories of reconsolidation in human episodic memory are discussed.
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neural correlates of auditory recognition under full and Divided Attention in younger and older adults
Neuropsychologia, 2006Co-Authors: Myra A Fernandes, Morris Moscovitch, Anda Pacura, Cheryl L GradyAbstract:We examined how aging affects the pattern of brain activity mediating retrieval under dual-task conditions. We used functional magnetic resonance imaging (fMRI) to measure brain activity in younger and older adults while they were engaged in an auditory verbal recognition test under either full or Divided Attention (FA or DA). During recognition under FA, older adults had more activity in bilateral dorsolateral prefrontal cortex (PFC). DA with a distracting task requiring animacy judgments to words disrupted memory more than did a task requiring odd-digit judgments to numbers. For both behavioural and brain measures we contrasted the two DA conditions to recognition under FA to identify interference with memory performance. Behaviourally, there were no age differences in the magnitude of memory interference from DA conditions, although recognition performance was poorer overall in older adults. During the DA animacy condition, younger adults showed an increase in recognition latency, and older adults an increase in distracting task costs. Younger adults in this condition showed an increase in left inferior PFC, coupled with a decrease in right hippocampal activity; these effects were diminished in older adults who instead showed an increase in bilateral middle frontal activity. During both DA conditions, older adults showed greater activity in posterior neocortex compared to the younger group. Results indicate that older adults are able to perform as well as younger adults on retrieval tasks under DA conditions due to two alterations in brain activity: a dampening of the changes characterizing younger adults during the DA animacy condition and greater recruitment of additional regions during both DA tasks.
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Divided Attention and memory evidence of substantial interference effects at retrieval and encoding
Journal of Experimental Psychology: General, 2000Co-Authors: Myra A Fernandes, Morris MoscovitchAbstract:In 5 Divided Attention (DA) experiments, students (24 in each experiment) performed visual distracting tasks (e.g., recognition of words, word and digit monitoring) while either simultaneously encoding an auditory word list or engaging in oral free recall of the target word list. DA during retrieval, using either of the word-based distracting tasks, produced relatively larger interference effects than the digit-monitoring task. DA during encoding produced uniformly large interference effects, regardless of the type of distracting task. Results suggest that when Attention is Divided at retrieval, interference is created only when the memory and concurrent task compete for access to word-specific representational systems; no such specificity is necessary to create interference at encoding. During encoding, memory and concurrent tasks compete primarily for general resources, whereas during retrieval, they compete primarily for representational systems.
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source memory and Divided Attention reciprocal costs to primary and secondary tasks
Neuropsychology (journal), 1999Co-Authors: Angela K Troye, Fergus I M Craik, Gordo Winocu, Morris MoscovitchAbstract:Source memory, in comparison with item memory, is more sensitive to frontal lesions and may require more strategic processing. Divided Attention was used to restrict Attentional resources and strategic processing on memory tasks. Participants encoded and retrieved items (i.e., words) and source (i.e., voice or spatial location) while concurrently performing a finger-tapping (FT) or visual reaction-time (VRT) task. Memory accuracy costs under Divided Attention were greater for retrieval of source than item and were greater with VRT than FT. Similarly, costs to the secondary task were greater when concurrently retrieving source as opposed to item and were greater for VRT than FT. Effects were stronger when spatial location was used as the source task. Findings support the idea that processing source information requires more Attentional resources and effort than processing item information. Furthermore, concurrent performance of VRT produced greater interference with a task that was more dependent on intact frontal functioning and better simulated the performance of patients with frontal dysfunction.
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Divided Attention impairments after traumatic brain injury
Neuropsychologia, 1999Co-Authors: Norma W Park, Morris Moscovitch, Ia H RobertsoAbstract:This research investigated whether people with severe traumatic brain injury (TBI) are impaired on Divided Attention tasks requiring working memory. In experiment 1, a severe TBI and control group performed two tasks requiring working memory separately and concurrently. Results showed that the TBI group had impaired Divided Attention when performing the two tasks concurrently, although the two groups did not differ in performance when these tasks were performed separately. Experiment 2 showed that performance on the paced auditory serial addition task improved with increases in the intertrial interval for both TBI and control groups. A meta-analysis showed that TBIs are impaired on Divided Attention when the tasks require controlled processing, but not when the tasks can be carried out relatively automatically.
Josette Couille - One of the best experts on this subject based on the ideXlab platform.
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rehabilitation of Divided Attention after severe traumatic brain injury a randomised trial
Neuropsychological Rehabilitation, 2010Co-Authors: Josette Couille, Stephane Soury, Gaelle Lebornec, Sybille Aslou, P A Joseph, J M Mazau, P AzouviAbstract:Patients with severe traumatic brain injury (TBI) frequently suffer from a difficulty in dealing with two tasks simultaneously. However, there has been little research on the rehabilitation of Divided Attention. The objective of the present study was to assess the effectiveness of a rehabilitation programme for Divided Attention after severe TBI. Twelve patients at a subacute/chronic stage after a severe TBI were included. A randomised AB vs. BA cross-over design was used. Training lasted six weeks, with four one-hour sessions per week. It was compared to a non-specific (control) cognitive training. During experimental treatment, patients were trained to perform two concurrent tasks simultaneously. Each one of the two tasks was first trained as a single task, then both tasks were given simultaneously. A progressive hierarchical order of difficulty was used, by progressively increasing task difficulty following each patient's individual improvement. Patients were randomised in two groups: one starting with dual-task training, the other with control training. Outcome measures included target dual-task measures, executive and working memory tasks, non-target tasks, and the Rating Scale of Attentional Behaviour addressing Attentional problems in everyday life. Assessment was not blind to treatment condition. A significant training-related effect was found on dual-task measures and on the Divided Attention item of the Rating Scale of Attentional Behaviour. There was only little effect on executive measures, and no significant effect on non-target measures. These results suggest that training had specific effects on Divided Attention and helped patients to deal more rapidly and more accurately with dual-task situations.
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Divided Attention and mental effort after severe traumatic brain injury
Neuropsychologia, 2004Co-Authors: P Azouvi, Josette Couille, Sybille Aslou, Michel Leclercq, Yves Marti, M RousseauAbstract:The aim of this study was to assess dual-task performance in TBI patients, under different experimental conditions, with or without explicit emphasis on one of two tasks. Results were compared with measurement of the subjective mental effort required to perform each task. Forty-three severe TBI patients at the subacute or chronic phase performed two tasks under single- and dual-task conditions: (a) random generation; (b) visual go-no go reaction time task. Three dual-task conditions were given, requiring either to consider both tasks as equally important or to focus preferentially on one of them. Patients were compared to matched controls. Subjective mental effort was rated on a visual analogic scale. TBI patients showed a disproportionate increase in reaction time in the go-no go task under the dual-task condition. However, they were just as able as controls to adapt performance to the specific instructions about the task to be emphasised. Patients reported significantly higher subjective mental effort, but the variation of mental effort according to task condition was similar to that of controls. These results suggest that the Divided Attention deficit of TBI patients is related to a reduction in available processing resources rather than an impairment of strategic processes responsible for Attentional allocation and switching. The higher level of subjective mental effort may explain why TBI patients frequently complain of mental fatigue, although this subjective complaint seems to be relatively independent of cognitive impairment.
Kimmo Alho - One of the best experts on this subject based on the ideXlab platform.
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brain activity associated with selective Attention Divided Attention and distraction
Brain Research, 2017Co-Authors: Emma Salo, Viljami Salmela, Juha Salmi, Jussi Nummine, Kimmo AlhoAbstract:Top-down controlled selective or Divided Attention to sounds and visual objects, as well as bottom-up triggered Attention to auditory and visual distractors, has been widely investigated. However, no study has systematically compared brain activations related to all these types of Attention. To this end, we used functional magnetic resonance imaging (fMRI) to measure brain activity in participants performing a tone pitch or a foveal grating orientation discrimination task, or both, distracted by novel sounds not sharing frequencies with the tones or by extrafoveal visual textures. To force focusing of Attention to tones or gratings, or both, task difficulty was kept constantly high with an adaptive staircase method. A whole brain analysis of variance (ANOVA) revealed fronto-parietal Attention networks for both selective auditory and visual Attention. A subsequent conjunction analysis indicated partial overlaps of these networks. However, like some previous studies, the present results also suggest segregation of prefrontal areas involved in the control of auditory and visual Attention. The ANOVA also suggested, and another conjunction analysis confirmed, an additional activity enhancement in the left middle frontal gyrus related to Divided Attention supporting the role of this area in top-down integration of dual task performance. Distractors expectedly disrupted task performance. However, contrary to our expectations, activations specifically related to the distractors were found only in the auditory and visual cortices. This suggests gating of the distractors from further processing perhaps due to strictly focused Attention in the current demanding discrimination tasks.