Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition, 2021
Temporal and semantic associative processes during the acquisition of new verbal information unde... more Temporal and semantic associative processes during the acquisition of new verbal information undergo various changes across the life span. Temporal order clusters and subjective clusters were monitored during verbal learning trials using the Rey (Auditory Verbal Learning Task) for 1471 participants aged 8-91. Pairs, three-word, and four-word clusters were measured. Subjective clusters were generated at similar frequency across the whole life span. By contrast, a clear inverted-U curve across life span was indicated for temporal clusters. More words were subjectively clustered than clustered by temporal presentation order. The number of words clustered increased across trials, and cluster types showed a different increase profile across trials. The subjective cluster increment was faster and steeper than the temporal cluster increment in most of the age segments. Life span trajectory tendencies in the formation of temporal and semantic associations in recall were interpreted in relat...
Background: Integrative research review infers generalizations about a substantive subject, summa... more Background: Integrative research review infers generalizations about a substantive subject, summarizes the accumulated knowledge that research has left unresolved and generates a new framework on these issues. Due to methodological issues emerging from working memory (WM) studies in the population with non-specific intellectual disability (NSID) (N = 64) between 1990–2014, it is difficult to conclude on WM performance in this popula-
Sequence learning is the cognitive faculty enabling everyday skill acquisition. In the lab, it is... more Sequence learning is the cognitive faculty enabling everyday skill acquisition. In the lab, it is typically measured in speed of response to sequential stimuli, whereby faster responses are taken to indicate improved anticipation. However, response speed is an indirect measure of anticipation, that can provide only limited information on underlying processes. As a result, little is known about what is learned during sequence learning, and how that unfolds over time. In this work, eye movements that occurred before targets appeared on screen in an ocular serial reaction time (O-SRT) task provided an online indication of where participants anticipated upcoming targets. When analyzed in the context of the stimuli preceding them, oculomotor anticipations revealed several simultaneous learning processes. These processes influenced each other, as learning the task grammar facilitated acquisition of the target sequence. However, they were dissociable, as the grammar was similarly learned w...
Annals of Physical and Rehabilitation Medicine, 2021
BACKGROUND Traumatic brain injury (TBI) is a steadily rising health concern associated with signi... more BACKGROUND Traumatic brain injury (TBI) is a steadily rising health concern associated with significant risk of emotional, behavioral and cognitive impairments. Cognitive memory impairment is one of the most concerning outcomes after TBI, affecting a wide range of everyday activities, social interactions and employment. Several comparative and comprehensive reviews on the effects of cognitive interventions in individuals with TBI have been conducted but usually with a qualitative rather than quantitative approach. Thus, evidence synthesis of the effects of TBI interventions on memory difficulties is limited. OBJECTIVE In this meta-analysis, we examined the memory-remediating effects of internal and external interventions, injury severity and the interaction of both factors for patients with TBI. METHOD Data were extracted from studies published between 1980 and 2020 that used objective memory measures (computerized or pencil-and-paper), and multiple meta-analyses were conducted to compare effectiveness across these interventions. Publication bias was assessed, as was quality of evidence using the Cochrane Risk of Bias tool for randomized controlled studies. RESULTS Our final meta-analysis included 16 studies of 17 interventions classified into 3 categories: internal, external and mixed. Mixed interventions demonstrated the highest average effect size for memory difficulties (Morris d = 0.79). An evaluation of injury severity yielded 2 categories: mild-moderate and moderate-severe. Analyses demonstrated a homogenous medium effect size of improvement across injury severity, with moderate-severe injury with the largest average effect size (Morris d = 0.65). Further evaluation of injury severity interaction with intervention type revealed a mediating effect for both factors, demonstrating the largest effect size for mixed interventions with moderate-severe injury (Morris d = 0.81). CONCLUSION This study highlights the effectiveness of memory remediation interventions on memory impairment after TBI. A wide range of interventions are more effective because they address individual variability for severity and memory deficits. The study further supports and expands existing intervention standards and guidelines.
Many studies have reported impaired selective attention in the elderly. Recent studies have isola... more Many studies have reported impaired selective attention in the elderly. Recent studies have isolated various underlying mechanisms of selective attention such as excitation, inhibition, and habituation. In the present study, 50 young adults and 50 elderly participants were ...
This study presents two experiments that explored consolidation of implicit sequence learning bas... more This study presents two experiments that explored consolidation of implicit sequence learning based on two dependent variables—reaction time (RT) and correct anticipations to clarify the role of sleep, and whether the manual component is necessary for consolidation processes. Experiment 1 ( n = 37) explored the performance of adults using an ocular variant of the serial reaction time task (O-SRT) with manual activation (MA), and Experiment 2 ( n = 37) used the ocular activation (OA) version of the task. Each experiment consisted of a Day and a Night group that performed two sessions of the O-SRT with an intervening 12-h offline period (morning/evening in Day group, evening/following morning in Night group). Night offline had an advantage only when manual response was required and when correct anticipations (i.e., accuracy) but not RT (i.e., speed) were measured. We associated this finding with the dual-learning processes required in the MA O-SRT that led to increased sequence specific learning overnight. When using the OA O-SRT, both groups demonstrated similar rates after offline in RT and correct anticipations. We interpreted this finding to reflect stabilization, which confirmed our hypothesis. As expected, all the groups demonstrated reduced performance when another sequence was introduced, thus reflecting sequence-specific learning. This study used a powerful procedure that allows measurement of implicit sequence learning in several ways: by evaluating two different measures (RT, correct anticipations) and by isolating different aspects of the task (i.e., with/without the manual learning component, more/less general skill learning), which are known to affect learning and consolidation.
While explicit memory in amnesics is impaired, their implicit memory remains preserved. Memory im... more While explicit memory in amnesics is impaired, their implicit memory remains preserved. Memory impairment is one of the side eects of electroconvulsive therapy (ECT). ECT patients are expected to show impairment on explicit but not implicit tasks. The present study examined 17 normal controls and 17 patients with severe major depressive disorder who underwent right unilateral ECT. Patients were tested in three sessions: 24±48 hours prior to, 24±48 hours following the ®rst ECT, and 24±48 hours following the eighth ECT. The controls were tested in three sessions, at time intervals that paralleled those of the patients. Implicit memory was tested by the perceptual priming task Ð Partial Picture-Identi®cation (PPI). The skill learning task used entailed solving the Tower of Hanoi puzzle (TOHP). Explicit memory was tested by picture recall from the PPI task, verbal recall of information regarding the TOHP, and by the Visual Paired Association (VPA) test. Results showed that explicit que...
The ability to chain together sequences of information and action is pivotal to everyday acquisit... more The ability to chain together sequences of information and action is pivotal to everyday acquisition of skills. Despite extensive research of sequence learning, little focus has been given to individual performance in standard tasks measuring this capability. As a result, little is known regarding what knowledge participants gain during such tasks. In the current work, an individualand item-based analysis is performed of eye movements that occur during a spatial sequence learning task and reflect anticipation of upcoming target locations. We show that the knowledge participants acquire during the task is tightly linked to a-priori response biases they bring into the experiment. Results suggest that a-priori biases may be a sizeable influence on performance in learning experiments, that tends to be overlooked. Implications for designing and reading studies of sequence learning are discussed.
Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition, 2021
Temporal and semantic associative processes during the acquisition of new verbal information unde... more Temporal and semantic associative processes during the acquisition of new verbal information undergo various changes across the life span. Temporal order clusters and subjective clusters were monitored during verbal learning trials using the Rey (Auditory Verbal Learning Task) for 1471 participants aged 8-91. Pairs, three-word, and four-word clusters were measured. Subjective clusters were generated at similar frequency across the whole life span. By contrast, a clear inverted-U curve across life span was indicated for temporal clusters. More words were subjectively clustered than clustered by temporal presentation order. The number of words clustered increased across trials, and cluster types showed a different increase profile across trials. The subjective cluster increment was faster and steeper than the temporal cluster increment in most of the age segments. Life span trajectory tendencies in the formation of temporal and semantic associations in recall were interpreted in relat...
Background: Integrative research review infers generalizations about a substantive subject, summa... more Background: Integrative research review infers generalizations about a substantive subject, summarizes the accumulated knowledge that research has left unresolved and generates a new framework on these issues. Due to methodological issues emerging from working memory (WM) studies in the population with non-specific intellectual disability (NSID) (N = 64) between 1990–2014, it is difficult to conclude on WM performance in this popula-
Sequence learning is the cognitive faculty enabling everyday skill acquisition. In the lab, it is... more Sequence learning is the cognitive faculty enabling everyday skill acquisition. In the lab, it is typically measured in speed of response to sequential stimuli, whereby faster responses are taken to indicate improved anticipation. However, response speed is an indirect measure of anticipation, that can provide only limited information on underlying processes. As a result, little is known about what is learned during sequence learning, and how that unfolds over time. In this work, eye movements that occurred before targets appeared on screen in an ocular serial reaction time (O-SRT) task provided an online indication of where participants anticipated upcoming targets. When analyzed in the context of the stimuli preceding them, oculomotor anticipations revealed several simultaneous learning processes. These processes influenced each other, as learning the task grammar facilitated acquisition of the target sequence. However, they were dissociable, as the grammar was similarly learned w...
Annals of Physical and Rehabilitation Medicine, 2021
BACKGROUND Traumatic brain injury (TBI) is a steadily rising health concern associated with signi... more BACKGROUND Traumatic brain injury (TBI) is a steadily rising health concern associated with significant risk of emotional, behavioral and cognitive impairments. Cognitive memory impairment is one of the most concerning outcomes after TBI, affecting a wide range of everyday activities, social interactions and employment. Several comparative and comprehensive reviews on the effects of cognitive interventions in individuals with TBI have been conducted but usually with a qualitative rather than quantitative approach. Thus, evidence synthesis of the effects of TBI interventions on memory difficulties is limited. OBJECTIVE In this meta-analysis, we examined the memory-remediating effects of internal and external interventions, injury severity and the interaction of both factors for patients with TBI. METHOD Data were extracted from studies published between 1980 and 2020 that used objective memory measures (computerized or pencil-and-paper), and multiple meta-analyses were conducted to compare effectiveness across these interventions. Publication bias was assessed, as was quality of evidence using the Cochrane Risk of Bias tool for randomized controlled studies. RESULTS Our final meta-analysis included 16 studies of 17 interventions classified into 3 categories: internal, external and mixed. Mixed interventions demonstrated the highest average effect size for memory difficulties (Morris d = 0.79). An evaluation of injury severity yielded 2 categories: mild-moderate and moderate-severe. Analyses demonstrated a homogenous medium effect size of improvement across injury severity, with moderate-severe injury with the largest average effect size (Morris d = 0.65). Further evaluation of injury severity interaction with intervention type revealed a mediating effect for both factors, demonstrating the largest effect size for mixed interventions with moderate-severe injury (Morris d = 0.81). CONCLUSION This study highlights the effectiveness of memory remediation interventions on memory impairment after TBI. A wide range of interventions are more effective because they address individual variability for severity and memory deficits. The study further supports and expands existing intervention standards and guidelines.
Many studies have reported impaired selective attention in the elderly. Recent studies have isola... more Many studies have reported impaired selective attention in the elderly. Recent studies have isolated various underlying mechanisms of selective attention such as excitation, inhibition, and habituation. In the present study, 50 young adults and 50 elderly participants were ...
This study presents two experiments that explored consolidation of implicit sequence learning bas... more This study presents two experiments that explored consolidation of implicit sequence learning based on two dependent variables—reaction time (RT) and correct anticipations to clarify the role of sleep, and whether the manual component is necessary for consolidation processes. Experiment 1 ( n = 37) explored the performance of adults using an ocular variant of the serial reaction time task (O-SRT) with manual activation (MA), and Experiment 2 ( n = 37) used the ocular activation (OA) version of the task. Each experiment consisted of a Day and a Night group that performed two sessions of the O-SRT with an intervening 12-h offline period (morning/evening in Day group, evening/following morning in Night group). Night offline had an advantage only when manual response was required and when correct anticipations (i.e., accuracy) but not RT (i.e., speed) were measured. We associated this finding with the dual-learning processes required in the MA O-SRT that led to increased sequence specific learning overnight. When using the OA O-SRT, both groups demonstrated similar rates after offline in RT and correct anticipations. We interpreted this finding to reflect stabilization, which confirmed our hypothesis. As expected, all the groups demonstrated reduced performance when another sequence was introduced, thus reflecting sequence-specific learning. This study used a powerful procedure that allows measurement of implicit sequence learning in several ways: by evaluating two different measures (RT, correct anticipations) and by isolating different aspects of the task (i.e., with/without the manual learning component, more/less general skill learning), which are known to affect learning and consolidation.
While explicit memory in amnesics is impaired, their implicit memory remains preserved. Memory im... more While explicit memory in amnesics is impaired, their implicit memory remains preserved. Memory impairment is one of the side eects of electroconvulsive therapy (ECT). ECT patients are expected to show impairment on explicit but not implicit tasks. The present study examined 17 normal controls and 17 patients with severe major depressive disorder who underwent right unilateral ECT. Patients were tested in three sessions: 24±48 hours prior to, 24±48 hours following the ®rst ECT, and 24±48 hours following the eighth ECT. The controls were tested in three sessions, at time intervals that paralleled those of the patients. Implicit memory was tested by the perceptual priming task Ð Partial Picture-Identi®cation (PPI). The skill learning task used entailed solving the Tower of Hanoi puzzle (TOHP). Explicit memory was tested by picture recall from the PPI task, verbal recall of information regarding the TOHP, and by the Visual Paired Association (VPA) test. Results showed that explicit que...
The ability to chain together sequences of information and action is pivotal to everyday acquisit... more The ability to chain together sequences of information and action is pivotal to everyday acquisition of skills. Despite extensive research of sequence learning, little focus has been given to individual performance in standard tasks measuring this capability. As a result, little is known regarding what knowledge participants gain during such tasks. In the current work, an individualand item-based analysis is performed of eye movements that occur during a spatial sequence learning task and reflect anticipation of upcoming target locations. We show that the knowledge participants acquire during the task is tightly linked to a-priori response biases they bring into the experiment. Results suggest that a-priori biases may be a sizeable influence on performance in learning experiments, that tends to be overlooked. Implications for designing and reading studies of sequence learning are discussed.
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