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Logical memory subtest of the Wechsler Memory Scale: age and education norms and alternate-form reliability of two scoring systems.

The Logical Memory (LM) subtest of the Wechsler Memory Scale has been characterized by imprecise scoring instructions which can make data interpretation and study comparisons difficult. A total of 339 adults, from 18 to 83 years old, took either Form I or Form II of the LM. Verbal recall of the story passages was evaluated using gist and verbatim scoring systems. Interrater reliability was very high for both scoring approaches. The two forms were equivalent for gist recall. However, verbatim recall of Form I was more difficult than Form II because the former consists of more words to remember. Recall was related more to educational level than to age. For both gist and verbatim scoring, age and education norms were generated for immediate, delayed, and 24-h recall.

Adolescent↗

Contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals.

The purpose of the study was to assess contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals. Subjects read short passages which differed in their contextual relatedness to target sentences, and then recalled those target sentences. It was found that large differences distinguished the performance of the young from the elderly on the free recall task; that cueing aided the performance of the young and the elderly-normal more than the aged-impaired; and lastly, that no differences were found in recognition performance between young and aged normals whereas the performance of the aged-impaireds was significantly poorer than either the young or the aged-normal group. The results were interpreted in light of two hypothetical mechanisms; the first is labeled "normal" aging and the second, "pathological" aging.

Adolescent↗

Replacement of the Faces subtest by Visual Reproductions within Wechsler Memory Scale-Third Edition (WMS-III) visual memory indexes: implications for discrepancy analysis.

Within discrepancy analysis differences between scores are examined for abnormality. Although larger differences are generally associated with rising impairment probabilities, the relationship between discrepancy size and abnormality varies across score pairs in relation to the correlation between the contrasted scores in normal subjects. Examinee ability level also affects the size of discrepancies observed normally. Wechsler Memory Scale-Third Edition (WMS-III) visual index scores correlate only modestly with other Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and WMS-III index scores; consequently, differences between these scores and others have to be very large before they become unusual, especially for subjects of higher intelligence. The substitution of the Faces subtest by Visual Reproductions within visual memory indexes formed by the combination of WMS-III visual subtests (creating immediate recall, delayed recall, and combined immediate and delayed index scores) results in higher correlation coefficients, and a decline in the discrepancy size required to surpass base rate thresholds for probable impairment. This gain appears not to occur at the cost of a diminished sensitivity to diverse pathologies. New WMS-III discrepancy base rate data are supplied to complement those currently available to clinicians.

Face↗

Age-associated memory impairment of Logical Memory and Visual Reproduction.

The standardization sample from the WMS-III (weighted N = 1250) (The Psychological Corporation, 1997; Tulsky & Ledbetter, 2000), which varied in age from 16 to 89, was used to determine whether storage of verbal and spatial information was affected by normal aging. A previous study with the same sample using an analysis of variance approach showed that the age-associated deterioration for Logical Memory (LM) and Visual Reproduction (VR) delayed recall and recognition were comparable and largely explained by poor immediate recall. This led to the conclusion that age-associated memory impairment was due primarily to encoding deficits. However, that study did not control for the age-associated deterioration in immediate recall in order to ensure that the small age-associated effects for delayed recall and recognition were not confounded by the fact that the elderly had less to remember on the delayed recall and recognition trials. The current study used covariance analysis to statistically adjust the dependent measures, LM and VR delayed recall and recognition, based on immediate recall scores. These analyses showed that the age-associated changes in these measures were statistically significant, but the effect sizes were very small. Partial eta(2) for the main effect of age for LM was 0.06 with weak effect sizes for the interaction of recall type and age (0.02). The partial eta(2) for the main effect of age for VR was 0.09, and the interaction of recall type and age (0.04). This pattern of findings shows that after adjustment for immediate recall, LM and VR recall and recognition demonstrated comparable, slight declines with age suggesting that normal aging produced minimal changes in the ability to store new information when age-associated changes in initial encoding and retrieval were statistically controlled.

Adolescent↗

Aging and memory control beliefs: performance in relation to goal setting and memory self-evaluation.

We examined memory control beliefs in relation to memory performance and beliefs in the context of goal setting. Control beliefs showed significant effects on performance and self-efficacy. Higher goals were set by high-control younger adults than by older adults and low-control younger adults. Individuals with a high sense of control performed higher and maintained performance over trials regardless of whether they set explicit goals. Those with low control (primarily older adults) performed lower, but they achieved increased performance when motivated by goals. These results emphasized that performance limitations associated with low control can be overcome with goals, even in older adults. As with previous studies, however, younger adults showed a more positive response to goals than older adults.

Achievement↗

Anti-cholinergic drugs and memory: the effects of benzhexol on memory in a group of geriatric patients.

A double blind trial on the effects of 2 mg of benzhexol on memory was performed on thirteen elderly subjects without cognitive impairment. The tests given 90 minutes after the drug or placebo involved learning a list of ten words, a paired-associate learning task, learning a short story and a test of digit span. Subjects were asked to recall the word list one minute after an interfering task, and 6 items from the story directly. Digit span involved immediate recall and the paired learning was measured by the number of trials necessary to learn. All tests were significantly impaired by the benzhexol except for digit span. This suggests that muscarinic blocking drugs should be avoided in the elderly, as they mimic the memory deficits found in senile dementia of Alzheimer type.

Aged↗

[Management of memory disorders in anxious patients consulting a memory clinic].

The proportion of patients consulting pluridisciplinary memory clinics who present anxiety disorders varies with recruitment and referral practices but often exceeded 10p.100. Most of these subjects have an anxiety trait or stress-related generalized anxiety, often triggered by diagnosis of Alzheimer's disease in a close friend or relation. The consultant should play special attention to analyzing the complaint in order to disclose difficulties in attention, true "loss of memory" events, and any recent traumatic events. The psychometric examination is generally normal or evidences discrete frontal dysfunction. Other diagnoses should be ruled out: associated depression, iatrogenic effect, alcoholism, anxiety as a sign of a somatic disease. Management may include drugs, usually on a short term regimen. Short-term psychotherapy or group therapy may be helpful.

Anxiety↗

A within-subjects, within-task demonstration of intact spatial reference memory and impaired spatial working memory in glutamate receptor-A-deficient mice.

Gene-targeted mice lacking the AMPA receptor subunit glutamate receptor-A (GluRA) (GluR1) and wild-type controls were compared on a radial-maze task in which the same three of six arms were always baited, but in which the rewards of milk were not replaced within a trial. This procedure allowed not only a within-subjects but also a within-trials assessment of both spatial working memory (WM) and reference memory (RM) in GluRA-/- mice, using identical spatial cues. In experiment 1, the GluRA-/- mice made more WM and RM errors during task acquisition. However, separate groups of GluRA-/- and wild-type mice (experiment 2) acquired a purely RM version of the task at a similar rate, using a paradigm with which it was not possible to make WM errors (doors prevented mice from re-entering an arm that they had already visited on that trial). In contrast, mice with hippocampal lesions were dramatically impaired. These results are consistent with the possibility that the WM impairment in the GluRA-/- mice during experiment 1 produced interference that disrupted RM acquisition. A WM component was therefore introduced after RM acquisition in experiment 2 (i.e., the mice were no longer prevented from re-entering a previously visited arm). The GluRA-/- mice now made considerably more WM errors than did wild-type mice, but simultaneously, RM was only mildly and transiently impaired. These experiments provide additional evidence of a selective spatial WM deficit coexisting with intact spatial RM acquisition in GluRA-/- mice, suggesting that different neuronal mechanisms within the hippocampus may support these different kinds of information processing.

Animals↗

Characteristics of immunological memory in mice. II. Resistance of nonrecirculating memory cells to antigen-mediated suppression of the secondary antibody response.

Mice were primed and subsequently challenged at various times with subcutaneous injections of sheep erythrocytes, and some characteristics of the secondary responses in the draining brachial and axillary lymph nodes were investigated. It was found that the secondary response within primed nodes was resistant to immunological preemption, a competition-like phenomenon which severely depresses primary responses. Since it was also shown that circulating memory cells could be inhibited by preempting injections of antigen, it was concluded that the resistance of primed nodes to preemption was due to the presence within them of a nonrecirculating subpopulation of memory cells. The size of this population was dependent both on the amount of priming antigen and the time after priming. The observation that the response given by these cells remained unaffected by doses of antigen which could depress a primary response does not favor the view that suppression of immune responses by preemption or antigenic competition is due to a factor which acts directly and indiscriminately on all immunologically competent cells.

Animals↗

Working memory and long-term memory for faces: Evidence from fMRI and global amnesia for involvement of the medial temporal lobes.

Behavioral studies with amnesic patients and imaging studies with healthy adults have suggested that medial temporal lobe (MTL) structures known to be essential for long-term declarative memory (LTM) may also be involved in the maintenance of information in working memory (WM). To examine whether MTL structures are involved in WM maintenance for faces, and the nature of that involvement, WM and LTM for faces were examined in normal participants via functional magnetic resonance imaging (fMRI) and in amnesic patients behaviorally. In Experiment 1, participants were scanned while performing a WM task in which they determined if two novel faces, presented 7 s apart, were the same or different. Later, participants' LTM for the faces they saw during the WM task was measured in an unexpected recognition test. During WM maintenance, the hippocampus was activated bilaterally, and there was greater activation during maintenance for faces that were later remembered than faces later forgotten. A conjunction analysis revealed overlap in hippocampal activations across WM maintenance and LTM contrasts, which suggested that the same regions were recruited for WM maintenance and LTM encoding. In Experiment 2, amnesic and control participants were tested on similar WM and LTM tasks. Amnesic patients, as a group, had intact performance with a 1-s maintenance period, but were impaired after a 7-s WM maintenance period and on the LTM task. Thus, parallel neuroimaging and lesion designs suggest that the same hippocampal processes support WM maintenance, for intervals as short as 7 s, and LTM for faces.

Adolescent↗

Neural correlates of memory retrieval during recognition memory and cued recall.

Regional brain activity, measured by H215O PET, was investigated during recognition memory and word-stem cued recall of words in order to compare the neural correlates of two components of memory retrieval-effort and success-as a function of task. For each task there was a baseline and two retrieval conditions. In one retrieval condition (zero density), none of the test items corresponded to words encoded in a preceding study phase. Differences in activity between this condition and the baseline were employed to characterize the neural correlates of retrieval effort in each task. In the other retrieval condition (high density), 80% of the test items had been studied previously. Differences in brain activity between this condition and the zero-density condition were taken to represent the neural correlates of successful retrieval. The principal findings concern the right anterior prefrontal cortex, a region demonstrated previously to be active during episodic retrieval. Relative to baseline, this region showed no evidence of activation in the zero-density condition of the recognition task, but did show enhanced activity in the equivalent condition of the cued-recall task. In contrast, relative to the zero-density condition, the high-density condition was associated with increased right prefrontal activity during recognition, but reduced activity during cued recall. It is proposed that the right prefrontal cortex supports cognitive processes that operate on information retrieved in response to a test item and that these processes contribute to the evaluation of whether the information represents an appropriate prior episode.

Adult↗

Similarities and differences in the neural correlates of episodic memory retrieval and working memory.

Functional neuroimaging studies have shown that different cognitive functions activate overlapping brain regions. An activation overlap may occur because a region is involved in operations tapped by different cognitive functions or because the activated area comprises subregions differentially involved in each of the functions. To investigate these issues, we directly compared brain activity during episodic retrieval (ER) and working memory (WM) using event-related functional MRI (fMRI). ER was investigated with a word recognition test, and WM was investigated with a word delayed-response test. Two-phase trials distinguished between retrieval mode and cue-specific aspects of ER, as well as between encoding/maintenance and retrieval aspects of WM. The results revealed a common fronto-parieto-cerebellar network for ER and WM, as well as subregions differentially involved in each function. Specifically, there were two main findings. First, the results differentiated common and specific subregions within the prefrontal cortex: (i) left dorsolateral areas were recruited by both functions, possibly reflecting monitoring operations; (ii) bilateral anterior and ventrolateral areas were more activated during ER than during WM, possibly reflecting retrieval mode and cue-specific ER operations, respectively; and (iii) left posterior/ventral (Broca's area) and bilateral posterior/dorsal areas were more activated during WM than during ER, possibly reflecting phonological and generic WM operations, respectively. Second, hippocampal and parahippocampal regions were activated not only for ER but also for WM. This result suggests that indexing operations mediated by the medial temporal lobes apply to both long-term and short-term memory traces. Overall, our results show that direct cross-function comparisons are critical to understand the role of different brain regions in various cognitive functions.

Adult↗

Age-related effects of alcohol on memory and memory-related brain function in adolescents and adults.

As detailed in this brief review, there is now clear evidence that adolescence represents a unique stage of brain development. Changes in brain organization and function during adolescence are widespread, and include intense rewiring in the frontal lobes and other neorcortical regions, as well as changes in a litany of subcortical structures. Recent research suggests that, because of these changes in brain function, drugs like alcohol affect adolescents and adults differently. The available evidence, much of it from research with animal models, suggests that adolescents might be more sensitive than adults to the memory impairing effects of alcohol, as well as the impact of alcohol on the brain function that underlies memory formation. For instance, when treated with alcohol, adolescent rats perform worse than adults in spatial learning tasks that are known to require the functioning of the hippocampus. Alcohol disrupts hippocampal function, and does so more potently in adolescents than adults. In contrast, adolescents appear to be far less sensitive than adults to both the sedative and motor impairing effects of alcohol. While research on this topic is still in its infancy, the findings clearly suggest that adolescence represents a unique stage of sensitivity to the impact of alcohol on behavior and brain function.

Adolescent↗

Place memory and scene memory: effects of fornix transection in the monkey.

Five experiments examined the effects of fornix transection upon some spatial and visual learning tasks in monkeys (Macaca fascicularis). For each trial of each task, the monkey was brought to a test tray and allowed to choose between 2 objects on the tray. In different tasks, different cues were provided by the experimenter to guide the monkey's choices. In total 5 different tasks were run (Experiments 1 to 5) and the results showed that the effects of fornix transection varied markedly between tasks: the animals with fornix transection were severely impaired in experiments 1, 3 and 5 but learned normally in experiments 2 and 4. It is concluded that the results cannot be explained by the simple hypothesis of a deficit in place learning, since some forms of place learning are unimpaired by fornix transection. A better general hypothesis is that the memory disrupted by fornix transection is like a snapshot memory, which stores the spatial arrangement of items in a witnessed scene.

Animals↗

The memory-facilitating effects of the competitive NMDA-receptor antagonist CGP 37849 are steroid-sensitive, whereas its memory-impairing effects are not.

The retention performance of mice in a passive-avoidance task was facilitated by low doses (0.3 mg/kg) of the competitive NMDA-receptor blocker CGP 37849, but impaired by high doses (30 mg/kg). The facilitatory effect was selectively suppressed by elevation of the plasma levels of aldosterone or corticosterone, or by blockade of steroid biosynthesis or the mineralocorticoid receptors. The impairment of memory, on the other hand, was not steroid sensitive. Accordingly, the data are in line with the hypothesis that drug induced memory facilitation is dependent on steroid sensitive processes.

2-Amino-5-phosphonovalerate↗

Aging and memory: corrections for age, sex and education for three widely used memory tests.

The associate learning subtest from the Wechsler Memory Scale; Benton's Visual Retention test and a Controlled Word Association Task (FAS) were administered to a random sample of normal, healthy individuals whose age ranged from 20 to 79 years, recruited within the Italian peninsula. The neuropsychological examination took place on a mobile unit and the tests were given by the same team of neuropsychologists to reduce variability among examiners. The Research Project was known as Progetto Memoria. Corrections to the scores of these tests were calculated for age, sex, and education. These corrected values will allow clinicians to screen for memory impairment with greater precision among normally aging individuals, thus improving differential diagnosis between physiologic and pathologic deterioration of cognitive functions.

Adult↗

Primary visual cortex and memory. Retinal position specificity and lack of size constancy at early stages of learning a visual memory task in the macaque.

Two monkeys were trained in a novel version of a delayed match-to-sample (DMS) task. They were required to fixate on a small spot at the center of the monitor and distinguish whether two gratings presented one after the other with delays up to 1.5 s in a specific visual field location were similar or not. It was found that such learning fails to transfer readily to other retinal locations. In fact, the learning was sensitive even to very small retinal displacements of the visual stimuli. Such acute retinal position specificity implies that at least a component of the learning in this particular memory task occurs at an early visual area such as the striate cortex, which has a fine-grain topographical representation. Furthermore, at early stages of learning the DMS task, when the monkeys had not generalized the learning to stimuli of different sizes, they failed to show size constancy. That is, when the display was placed at a different distance but with the same absolute size, the performance dropped. The performance was almost fully restored when, at the new display location, stimuli were changed to fit the original retinal size. This indicates that a crucial component of the learning does occur at a site even prior to size constancy. These results show that, under certain situations, an early visual area such as the primary visual cortex may be involved even in complex behaviours such as a memory task as more than just a feature-detecting area or a relay station.

Animals↗

Recall performance of children failing memory portions of a speech-language-memory screening battery.

Recall performance of first- and third-grade children who failed memory portions of a speech-language-memory screen was examined using digit and consonant-vowel (CV) stimulus sets. Children passing the screening battery had more accurate recall performance than children failing the screening battery. Systematic variations in performance as a function of stimulus set (i.e., digit vs CV) were noted in the groups: significantly lower recall was noted for CV items than for digit items in all groups passing or failing the screening battery. Data indicate children failing the screening battery differed quantitatively, rather than qualitatively, from children passing the screening battery. These data further suggest the difficulties experienced by children failing the screening battery may be related to deficits in the initial coding of auditory information.

Child↗