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PubMed2005

Spontaneous verbal labeling: visual memory and reading ability in children with cleft.

OBJECTIVE: The purpose of this study was to examine different types of short-term memory deficits (visual versus verbal) of children with cleft and to determine what type of memory deficits were associated with reading disorders. DESIGN: The study examined memory and reading in 48 consecutive cases of children with cleft, aged 7 to 9 years. A memory test designed to assess memory modalities (verbal-visual) was administered, along with tests of reading ability. RESULTS: Visual and verbal memory were examined with a one-way analysis of variance (ANOVA). The memory pattern indicated greatest deficit in visual memory. Two subgroups were formed, according to whether or not there was evidence of visual memory impairment. A hit rate predicting reading disability based on group membership was calculated to be 65%. Visual memory was significantly correlated with reading ability (r = .48). CONCLUSION: A brief visual memory test was almost as good as Full Scale IQ in predicting reading disability.

Anomia↗

PubMed2006

Diminished episodic memory awareness in older adults: evidence from feeling-of-knowing and recollection.

The ability to reflect on and monitor memory processes is one of the most investigated metamemory functions, and one of the important ways consciousnesses interacts with memory. The feeling-of-knowing (FOK) is one task used to evaluate individual's capacity to monitor their memory. We examined this reflective function of metacognition in older adults. We explored the contribution of metacognition to episodic memory impairment, in relation to the idea that older adults show a reduction in memory awareness characteristic of episodic memory. A first experiment showed that age affects the accuracy of FOK when predictions are made on an episodic memory task but not on a semantic memory task, suggesting a particular role for episodic memory awareness in metacognitive evaluations. A second experiment showed that the age-difference in episodic FOK accuracy was removed if one took into account subjective reports of memory awareness, or recollection. We argue that the FOK deficit specific to episodic memory is based on a lack of memory awareness manifest as a recollection deficit.

Adult↗

PubMed2003

Reduced levels of specific autobiographical memories in schizophrenia.

Autobiographical memory is intrinsically related to the self and personal identity. This study investigated whether both personal episodic memory and semantic memory are impaired in schizophrenia, a disease characterized by an abnormal personal identity. Personal episodic memory and personal semantic memory were investigated in 24 patients with schizophrenia and 24 normal subjects using an autobiographical fluency task and an autobiographical memory inquiry. Autobiographical memory scores and the proportion of specific memories were lower in patients with schizophrenia than in normal subjects. The deficit of personal episodic and semantic memory, as assessed by the autobiographical memory inquiry and the autobiographical fluency task, respectively, was most apparent after the onset of clinical symptoms. Schizophrenia is associated with an impairment of both personal episodic and semantic memory and with a reduction of specific autobiographical memories. Those impairments are consistent with the existence of an abnormal personal identity in patients with schizophrenia.

Adult↗

PubMed2004

Interpretative memories of artworks.

It is well known that memories of self-relevant experiences are reconstructed over time. Artworks often require an elongated period of interpretative meaning-making. Such works were therefore used to study temporal aspects of memory construction. In a longitudinal study, individuals' memories of artworks were examined to explore the idea that only with the passage of time would autobiographical memory and emotion be associated with thematic integration of the artwork memory. We also expected that integrated artwork memories would be more differentiated (in terms of number of details) than memories that were not integrated. Memories of artworks were collected from visitors to an art gallery in person as they left the gallery, and 5 months later in a phone interview. Participants were also asked, at both interviews, whether the memory recollection was associated with an autobiographical memory and with an emotion. Associations among the elements of autobiographical memory, emotion, differentiation, and integrated artwork memories were significant only at the time of the longer-term recollection. The data suggest that, during an incubation period, these elements moved from a state of disconnection to interconnection.

Adolescent↗

PubMed2006

Source and item memory for odors and objects in children and young adults.

Recall and recognition memory for odors are poorer in children than in adolescents. In addition, children perform worse than young adults on source memory tasks using visual and auditory stimuli. However, source memory for odor stimuli has not been examined in children. This study investigated source and item memory for odors and objects in children (7-10 years old) and young adults (18-24 years old). During the study phase, 1 male and 1 female experimenter (sources) randomly presented either 16 odors or 16 objects to the participant. Presentation alternated between sources so that each source presented 8 stimuli. Once the 16 stimuli were presented, the sources exited and a third experimenter began the test phase. To assess item recognition memory, a stimulus from the study phase and a novel stimulus were presented to the participant who was asked to choose the stimulus presented during the study phase. Source memory was assessed with the 8 stimuli from the study phase not used in the item memory task. The experimenter presented a stimulus and asked whether the male or female experimenter had presented the stimulus during the study phase. Results indicate that difference scores between item and source memory for odors were significantly larger for children than for young adults, indicating poorer source memory for children than adults. Difference scores for objects did not distinguish between groups. It has been suggested that the frontal lobes play a critical role in source memory and odor memory--a brain region that continues to develop into adolescence. Poor performance among children on the source memory task for odors may be due in part to immaturity of the frontal lobes.

Adolescent↗

PubMed2003

The effect of L-NAME and L-arginine on impairment of memory formation and state-dependent learning induced by morphine in mice.

RATIONALE: Morphine and nitric oxide (NO) have important functional interactions in different neural processes, and both modulate learning and memory although their interaction in cognitive performance has not been elucidated. OBJECTIVE: To examine the effect of the NO synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) and NOS substrate L-arginine on morphine-induced impairment of memory formation and the state-dependent retrieval of a passive avoidance task learned under morphine influence. METHODS: All drugs were administered intraperitoneally, and a one-trial step-down paradigm was used for the assessment of memory in adult male NMRI mice. Morphine was administered 30 min before training to induce impairment of memory formation and 30 min before test to induce state-dependent retrieval of the memory acquired under pre-training morphine influence. L-NAME or L-arginine was administered either 5 min after training or 45 min before the test. RESULTS: Pre-training morphine induced impairment of memory formation that was reversible by pre-test morphine but not saline. Post-training administration of L-arginine (200 mg/kg) and L-NAME (3, 10 and 30 mg/kg), respectively, facilitated and impaired the memory consolidation, but their pre-test injections did not affect retention. However, post-training L-arginine at per se non-effective doses of 20 mg/kg and 60 mg/kg reversed the morphine-induced impairment of memory formation. Pre-test administration of L-NAME (3 mg/kg and 10 mg/kg) could restore the memory impairment induced by pre-training morphine, and this effect was blocked by concomitant pre-test L-arginine (60 mg/kg). Concomitant administration of low doses of L-NAME (1 mg/kg) and morphine (0.5 mg/kg) pre-test also revealed an additive effect in restoring the morphine state of memory. CONCLUSION: These results suggest that the impairment of memory formation and the facilitation of retrieval induced by morphine involves decreased synthesis/release of NO and can be counteracted by NOS substrate.

Animals↗

PubMed1999

Do memory complaints indicate the presence of cognitive impairment? Results of a field study.

BACKGROUND: In the context of suspected cognitive disorders, the validity of memory complaints is subject to considerable debate. This investigation documents the prevalence of memory complaints and assesses the validity of memory complaints for detecting cognitive impairment. METHODS: The sample comprises 349 randomly selected non-institutionalized individuals, aged 75 and over living in the city of Leipzig. Twenty individuals who suffer from moderate and severe dementia according to DSM-III-R were excluded. Memory complaints were measured by means of a single item question. The Mini-Mental State Examination (MMSE) and a wider range of cognitive tests which constitute the short neuropsychological battery of the SIDAM (Structured Interview for the Diagnosis of dementia of Alzheimer type, Multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-III-R) were used to test cognitive performance. RESULTS: One in three individuals aged 75 and over complained about memory deficits. The MMSE is not significantly related to memory complaints, whereas poorer performance on 2 out of 8 tests regarding specific areas of cognitive function (immediate recall, short-term memory) were found to be significantly associated with memory complaints. Despite these statistically significant associations, it is shown that memory complaints do not have diagnostic validity in detecting cognitive impairment on the individual level. CONCLUSION: Memory self-assessment should not be used as a substitute measure of cognitive performance. Initiation of further diagnostic and therapeutic steps should be based on cognitive performance testing. Relaying solely on memory complaints would miss individuals in need and allocate resources to worried but cognitively healthy persons.

Aged↗

PubMedDate not supplied

Working memory deficits in BXSB mice with neocortical ectopias.

Approximately 40-60% of BXSB/MpJ-Yaa mice exhibit neocortical ectopias, which are misplaced clusters of neurons in layer I of cortex. These ectopias are usually located in the prefrontal and/or motor region of cortex in BXSB mice, and are similar in appearance to those found in postmortem analyses of the brains of dyslexic humans. Several within-strain learning differences between mice with ectopias and those without have been reported. In particular, ectopic BXSB mice exhibited superior reference memory learning, but inferior working memory learning in several studies from our laboratory. This study used the Morris water maze delayed matching-to sample task and the water radial-arm maze to asses working memory in female BXSB mice with and without ectopias. In the delayed matching-to sample task, a hidden escape platform remained in a constant position for each four-trial session, but changed position between sessions. Trial 2 was the measure of working memory, i.e., how well did the mouse remember where the platform was located for that session. In the water version of the eight-arm radial maze, hidden escape platforms were located in four of the eight arms, and each platform was removed from the maze once found. This enabled us to assess working and reference memory simultaneously. Ectopic mice demonstrated working memory deficits during the first part of the delayed matching-to sample task compared to nonectopics. Similarly, ectopics made more working memory errors during the latter half of radial-arm maze testing, while not differing from nonectopics in reference memory performance. Additionally, there were significant correlations between measures of working memory in the radial-arm maze and working memory in a delayed matching-to-sample task. These findings are in agreement with other studies demonstrating working memory deficits in ectopic BXSB mice.

Animals↗

PubMed2002

The effect of retrograde and anterograde glucose administration on memory performance in healthy young adults.

Memory for a list of 20 words can be enhanced by preceding learning by consumption of 25 g of glucose, compared with consumption of an equally sweet aspartame solution (Psychopharmacology 137 (1998) 259; Psychopharmacology 157 (2001) 46). However, using this anterograde administration procedure, it is impossible to separate whether glucose affects encoding, consolidation, or retrieval. The present placebo-controlled, double-blind study investigated the effect of anterograde and retrograde administration on memory performance in healthy young participants. In order to evaluate whether post-acquisition administration of glucose can improve memory performance and to compare possible differences in the size of the effect, participants were administered 25 g of glucose immediately before or immediately after presentation of a word list. Moreover, in order to investigate whether the effect of glucose administration on memory performance is time-dependent, a third group received 25 g of glucose 15 min before learning the word list. Word- list recall was tested 30 min and 24 h after word list presentation. Measures of spatial memory performance and working memory were also evaluated. The results of this study showed that both pre- and post-acquisition oral glucose administration (25 g) can improve memory performance. However, as the time interval between anterograde glucose administration and memory encoding increased, the glucose memory facilitation effect decreased. This study provides evidence that glucose enhances memory performance in healthy young people even when it is given after learning has taken place, and that this effect is observed at least up to 24 h after glucose administration. Moreover, it provides evidence that the effect of glucose on memory performance may be time-dependent, as the enhancement of retention was decreased when the administration-learning interval was increased.

Adult↗

PubMed2002

Prospective memory functioning in people with and without brain injury.

Prospective remembering has been relatively underinvestigated in neurological patients. This paper describes a group study in which the prospective memory performance of 36 people with brain injury and 28 control participants is compared. We used a new instrument, the Cambridge Behaviour Prospective Memory Test (CBPMT) to assess prospective memory. This comprises 4 time-based and 4 event-based tasks. Participants were allowed to take notes to help them remember the tasks. The relationships between CBPMT scores, scores on formal tests and subjective reports on memory, attention and executive functioning were analyzed. The key findings were that (1) note-taking significantly benefited prospective memory performance, (2) significant relationships were found between scores on the prospective memory test and scores on tests of memory and executive functions, and (3) participants had more difficulty with the time-based than with the event-based prospective memory tasks. The results suggest that compensatory strategies improve prospective memory functioning; memory for content as well as attention and executive functioning processes are involved in prospective memory; and that time-based tasks are more difficult than event-based tasks because they place higher demands on inhibitory control mechanisms. Discussion focuses on the implications of these results for neuropsychological assessment and rehabilitation.

Adaptation, Psychological↗

PubMed1990

Normal aging and prospective memory.

We develop a laboratory paradigm for studying prospective memory and examine whether or not this type of memory is especially difficult for the elderly. In two experiments, young and old subjects were given a prospective memory test (they were asked to perform an action when a target event occurred) and three tests of retrospective memory (short-term memory, free recall, and recognition). From the perspective that aging disrupts mainly self-initiated retrieval processes, large age-related decrements in prospective memory were anticipated. However, despite showing reliable age differences on retrospective memory tests, both experiments showed no age deficits in prospective memory. Moreover, regression analyses produced no reliable relation between the prospective and retrospective memory tasks. Also, the experiments showed that external aids and unfamiliar target events benefit prospective memory performance. These results suggest some basic differences between prospective and retrospective memory.

Adolescent↗

PubMed2004

Role for a cortical input to hippocampal area CA1 in the consolidation of a long-term memory.

A dialogue between the hippocampus and the neocortex is thought to underlie the formation, consolidation and retrieval of episodic memories, although the nature of this cortico-hippocampal communication is poorly understood. Using selective electrolytic lesions in rats, here we examined the role of the direct entorhinal projection (temporoammonic, TA) to the hippocampal area CA1 in short-term (24 hours) and long-term (four weeks) spatial memory in the Morris water maze. When short-term memory was examined, both sham- and TA-lesioned animals showed a significant preference for the target quadrant. When re-tested four weeks later, sham-lesioned animals exhibited long-term memory; in contrast, the TA-lesioned animals no longer showed target quadrant preference. Many long-lasting memories require a process called consolidation, which involves the exchange of information between the cortex and hippocampus. The disruption of long-term memory by the TA lesion could reflect a requirement for TA input during either the acquisition or consolidation of long-term memory. To distinguish between these possibilities, we trained animals, verified their spatial memory 24 hours later, and then subjected trained animals to TA lesions. TA-lesioned animals still exhibited a deficit in long-term memory, indicating a disruption of consolidation. Animals in which the TA lesion was delayed by three weeks, however, showed a significant preference for the target quadrant, indicating that the memory had already been adequately consolidated at the time of the delayed lesion. These results indicate that, after learning, ongoing cortical input conveyed by the TA path is required to consolidate long-term spatial memory.

Animals↗

PubMed2002

Memory outcome after selective amygdalohippocampectomy: a study in 140 patients with temporal lobe epilepsy.

PURPOSE: The technique of selective amygdalohippocampectomy (SAH) was originally developed in epilepsy surgery to spare unaffected brain tissue from surgery, thus minimizing the cognitive consequences of temporal lobe surgery. The results of previous studies, however, are equivocal in this regard. This study evaluated memory after SAH in a large sample of patients with mesial temporal lobe epilepsy. METHODS: The 140 patients received material-specific memory tests before and 3 months after unilateral SAH. RESULTS: Significant declines in all aspects of verbal learning and memory were found particularly for the left resected group. With reliability-of-change indices, a high number of patients showed postoperative verbal memory declines, < or = 51% in left SAH and < or = 32% in right SAH. For left SAH, a higher preoperative verbal memory performance, a lower preoperative nonverbal memory score, an older age at surgery, and a later onset of epilepsy predicted a stronger decline in verbal memory. After right SAH, the risk for a verbal memory decline was slightly increased when patients had surgical complications or a presurgical evaluation with bilateral intrahippocampal depth electrodes. Results concerning nonverbal memory were less clear. CONCLUSIONS: The results clearly indicate, that particularly left SAH can lead to a significant decline in memory functions. Predictors of postoperative verbal memory were similar to those reported for temporal lobectomy. Postoperative deteriorations were broader and stronger in our study than in previous studies. We discuss methodologic differences (sample size, retest interval, extent of resection) and other factors as possible reasons.

Adult↗

PubMedDate not supplied

Memory enhancement program for community-based older adults: development and evaluation.

The purpose of the study was to develop a multifactorial memory enhancement program for community-dwelling older adults aimed at encouraging positive beliefs and behaviors about memory function and abilities in later life. The study evaluated the effectiveness of cognitive restructuring techniques (56 subjects) as compared to traditional memory training techniques (61 subjects) for purposes of enhancing memory performance. Posttest assessments were conducted after 10 weeks of memory training. Follow-up assessments were conducted 9 weeks later to assess maintenance of memory performance and memory beliefs. Three 2 x 3 (Treatment x Time) repeated measures multivariate analyses of variance were conducted to evaluate the effects of two types of intervention on memory performance, memory perception, and affective symptomatology over time. Results suggest that cognitive restructuring techniques may help community-dwelling older adults gain control over their beliefs about memory and thereby enhance their memory performance.

Aged↗

PubMed1993

The importance of cue familiarity and cue distinctiveness in prospective memory.

Both retrospective cued-memory tasks and event-based prospective memory tasks require that cue and target information be associated, and that aspects of that association be reinstated for successful remembering. These functional similarities between retrospective memory and prospective memory were the bases for the hypothesis that the familiarity and the distinctiveness of the target event (cue) would influence prospective memory performance. Experiment 1, focusing on target familiarity, found a nominal advantage in prospective memory with unfamiliar target events. Experiment 2 showed a significant benefit for unfamiliar target events, as well as for target events that were distinctive relative to the local context. Additionally, prospective memory performance did not reliably correlate with explicit retrospective memory tasks (recall and recognition), but did correlate with an indirect retrospective memory task (word fragment completion). This pattern suggests and helps specify the general view that prospective memory processes may be similar to those involved in both direct and indirect tests of retrospective memory.

Analysis of Variance↗

PubMed1998

The neural substrates of memory systems impairment in Alzheimer's disease. A PET study of resting brain glucose utilization.

The aim of this study was to determine the neuronal basis for memory impairment in Alzheimer's disease by taking advantage of the clinical and metabolic heterogeneity of this pathology. To this end, 19 patients satisfying the NINCDSADRDA criteria for probably Alzheimer's disease of mild-to-moderate severity underwent a detailed examination of the five memory systems according to Tulving's model, together with a PET measurement of resting regional cerebral glucose utilization (CMRGlc). Compared with controls, the patients as a group showed the expected memory and metabolic profiles of impairment. Correlations (corrected for the effects of ageing) were calculated between memory scores and CMRGlc (normalized by the vermis CMRGlc) using two methods: (i) the classic regions-of-interest method, based on a priori hypotheses and individual coregistered structural MRI; and (ii) the statistical parametric mapping method which allows a systematic voxel-by-voxel analysis, in a more descriptive and exploratory way. Significant correlations were above chance levels and largely consistent between the two methods. They were almost exclusively positive (i.e. in the neurobiologically expected direction) and their distribution showed striking differences according to each memory system. Thus, verbal episodic memory impairment was related to changes in a large neuronal network including not only the limbic structures (mesial temporal cortex, thalamus and cingulate gyrus, with left side predominance) but also the parietotemporal and frontal association cortices of the right hemisphere, possibly on a compensatory basis. Regardless of modality, short-term memory tests were mainly correlated with bilateral activity in posterior association cortex, and also with activity in left prefrontal cortex for the visuospatial span, possibly indicating essentially uniform strategies for the performance of the different tasks. As predicted, semantic memory scores correlated with activity in temporoparietal and frontal association cortices of the left hemisphere, and also with activity in left cingulate cortex. Thus, for episodic, short-term and semantic memory, many findings fit classical neuropsychology, while most of the less expected ones were consistent with recent results from functional neuro-imaging in healthy subjects, notably with the hemispheric encoding/ retrieval asymmetry (HERA) model; only few findings suggested possible reorganization processes and/or recourse to unexpected cognitive strategy. Finally, only negative correlations were found for perceptual priming and procedural memory; although they could arise by chance, some of these unexpected findings give rise to interesting hypotheses about the cognitive relationships between the most and least affected memory systems. This study documents the validity and usefulness of our approach in unravelling the neural substrates of cognitive impairment in brain pathology without focal tissue loss such as that seen in neurodegenerative diseases.

Aged↗

PubMed1994

Midlatency auditory evoked potentials and explicit and implicit memory in patients undergoing cardiac surgery.

BACKGROUND: A high incidence of intraoperative awareness during cardiac surgery has been reported. Midlatency auditory evoked potentials (MLAEP) have been used recently as an indicator of awareness. In the current study, memory for information presented during anesthesia was investigated using MLAEP as one experimental indicator in 45 patients scheduled for elective cardiac surgery. METHODS: In all patients general anesthesia was maintained using high-dosage fentanyl (1.2 mg.h-1). In addition, the patients of group 1 (n = 10) received flunitrazepam (1.2 mg.h-1), the patients of group 2 (n = 10) isoflurane (0.6-1.2 vol%), and the patients of group 3 (n = 10) propofol (4-8 mg.kg-1.h-1). Group 4 (n = 15) served as a control, and those patients were assigned randomly to one of the anesthetic regimes. After sternotomy and before cardiopulmonary bypass, an audiotape, which included an implicit memory task, was presented to the patients of groups 1-3. Auditory evoked potentials were recorded while the patients were awake and during general anesthesia immediately before and after the audiotape presentation. Latencies of the brain stem peak V and the early cortical potentials Na and Pa were measured. RESULTS: Three to 5 days postoperatively no patient had a clear explicit memory of intraoperative events. However, there were statistically significant differences in the incidence of implicit recall among the groups. Five patients in the flunitrazepam-fentanyl group, 1 patient in the isoflurane-fentanyl group, 1 patient in the propofol-fentanyl group, and no patient in the control group showed an implicit memory of the intraoperative tape message. In the awake state, MLAEP showed high peak-to-peak amplitudes and a periodic waveform. In the patients with implicit memory postoperatively, MLAEP continued to show this pattern during general anesthesia. The early cortical potentials Na and Pa did not increase in latency or decrease in amplitude before or after the audiotape presentation. In contrast, in the patients without implicit memory, MLAEP waveform was severely attenuated or abolished. Na and Pa showed marked increases in latencies and decreases in amplitudes or were completely suppressed. In 9 patients, including all patients (7 of 9) with implicit memory, Pa latency increased less than 12 ms, and 21 of 23 patients without implicit memory showed a Pa latency increase of greater than 12 ms during anesthesia and the audiotape presentation. Therefore, the Pa latency increase of greater or less than 12 ms may provide sensitivity of 100% and specificity of 77% in distinguishing patients with implicit memory from patients without implicit memory postoperatively. CONCLUSIONS: When the early cortical potentials of MLAEP are preserved during general anesthesia, auditory information may be processed and remembered postoperatively by an implicit memory task.

Aged↗

PubMed1997

Functional anatomy of long-term memory.

Memory in the brain is organized into multiple memory systems that perform different memory functions and have different neurologic substrates. Declarative memory involves conscious memory for facts and events. The medial temporal lobe and structures in the diencephalon are essential in the establishment of new declarative memories, and these memory traces are finally stored in domain-specific regions of the cerebral cortex. The frontal lobe and basal ganglia are important in some forms of declarative memory that require reasoning about the contents of memory. Nondeclarative forms of memory (including skill learning, repetition priming, and classical conditioning) do not involve conscious recollection and are measured through changes in the way in which tasks are performed. These forms of memory rely upon the cerebral cortex, basal ganglia, and cerebellum.

Amygdala↗