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A D Baddeley

Publications and source records attributed to A D Baddeley.

At least 55 records · Page 3Linked to original sources

How do old dogs learn new tricks: teaching a technological skill to brain injured people.

Little is known about the way people learn technological skills. This investigation was carried out to see how 100 brain injured, 50 controls and two amnesic patients performed on a task requiring them to learn a six-step programme for an electronic memory aid. Performance was correlated with other measures of memory to determine whether the technological skill was similar to a procedural learning task, a spatial memory task, a visual task, a verbal task or an amalgam of these. All controls but only 59 percent of the patients learned the task within three trials. The two amnesic patients also failed to learn the new skill. There was a high correlation between overall performance on a standardized test of everyday memory (the Rivermead Behavioural Memory Test) but little evidence that the technological skill was similar to a procedural learning task; nor was it specifically related to visual, verbal or spatial memory. It is concluded that a combination of skills is required to learn the technological task. Implications for the concept of procedural learning are discussed.

Adolescent↗

Why are amnesic judgements of recency and frequency made in a qualitatively different way from those of normal people?

The Huppert and Piercy (1978) test of recency and frequency judgements was given to a group of 12 non-Korsakoff amnesics of mixed aetiology and to four non-amnesic patients with selective frontal lobe lesions. The results confirmed that non-Korsakoff amnesics show a significant tendency to base their recency and frequency judgements on memory strength and that amnesics with medial temporal lobe damage show this tendency at least with recency judgements. The patients with frontal lobe lesions performed like normal subjects. Patients who were dysexecutive or impaired in cognitive resources were less likely to base recency judgements on trace strength. Such a recency bias was not however, correlated with measures of amnesic severity. The tendency to base frequency judgements on memory strength was not related to either degree of amnesia or reduction of cognitive resources.

Adult↗

The autobiographical memory interview: a new assessment of autobiographical and personal semantic memory in amnesic patients.

This paper describes a new technique for assessing "autobiographical" and "personal semantic" memory in amnesic patients and healthy controls. It provides evidence of the reliability and validity of the procedure, and reports an age-related temporal gradient in amnesic patients. The results are considered in terms of the severity, the rate of onset, and the duration of the amnesia; and a preliminary analysis is given of the findings in different diagnostic groups. The findings indicate that autobiographical and personal semantic memory show a consistent pattern of impairment, when a comparison is made which controls for the age of the memories and the subject's own past experience.

Adult↗

Telescoping is not time compression: a model of the dating of autobiographical events.

A model of telescoping is proposed that assumes no systematic errors in dating. Rather, the overestimation of recent occurrences of events is based on the combination of three factors: (1) Retention is greater for recent events; (2) errors in dating, though unbiased, increase linearly with the time since the dated event; and (3) intrusions often occur from events outside the period being asked about, but such intrusions do not come from events that have not yet occurred. In Experiment 1, we found that recall for colloquia fell markedly over a 2-year interval, the magnitude of errors in psychologists' dating of the colloquia increased at a rate of .4 days per day of delay, and the direction of the dating error was toward the middle of the interval. In Experiment 2, the model used the retention function and dating errors from the first study to predict the distribution of the actual dates of colloquia recalled as being within a 5-month period. In Experiment 3, the findings of the first study were replicated with colloquia given by, instead of for, the subjects.

Attention↗

Primary and working memory functioning in Alzheimer-type dementia.

This paper reviews recent neuropsychological studies of primary-memory functioning in early Alzheimer-type dementia (AD) with specific reference to recent research on working memory. The deficits in primary memory follow a fairly distinct pattern with a comparatively unimpaired recency effect in free recall, a moderate impairment in memory span, and a more substantial impairment in short-term retention following distraction. The nature of these deficits is considered in relation to the Working Memory Model (Baddeley & Hitch, 1974). It is suggested that the Articulatory Loop System is functioning normally but that there is an impairment in the control processes of working memory.

Alzheimer Disease↗

Subjective memory assessment and test performance in elderly adults.

The everyday memory of a group of elderly adults was assessed using techniques developed for use with younger head-injured people (Sunderland et al., 1983). The participants completed a memory questionnaire and a daily checklist; their spouses gave their assessment using a separate questionnaire. These subjective methods showed only moderate agreement, and the questionnaire had low test-retest reliability. It appears that these methods of subjective memory assessment have little validity when used with normal elderly adults. Two positive findings did emerge: As in previous studies, a story recall test was the strongest predictor of reported memory performance; and despite a universal belief among elderly adults that their memory had deteriorated with age, very few of them felt that they were at all handicapped by forgetfulness in everyday life.

Aged↗

Implications of neuropsychological evidence for theories of normal memory.

The relation between neuropsychology and the study of normal cognitive function is discussed in the context of recent research on human memory. It is suggested that neuropsychological evidence has clear implications for the fractionation of human memory into subsystems. The distinction between long-term and short-term memory, between semantic and episodic memory, and the further fractionation of short-term or working memory all offer examples of concepts that have been successfully applied within the neuropsychological domain, and where the neuropsychological evidence has led to a modification and development of the original concept. Attempts to offer a cognitive interpretation of the amnesic syndrome are discussed. While none of these is entirely satisfactory, such work has led to a potentially important distinction between autobiographical memory or recollection, which is defective in amnesic patients, and a more perceptual or procedural learning process, which appears to be intact in such patients. Recent research on normal subjects is beginning to reveal a similar distinction. It is concluded that the relation between neuropsychology and the study of normal cognitive function continues to be an extremely fruitful one.

Amnesia↗

When face recognition fails.

Two studies investigated recognition of pictures of faces, focusing on the effects of changes in appearance of the face from presentation to test and type of processing or encoding. Experiment 1 demonstrated that (a) previously seen faces changed in pose and facial expression were discriminated from "new" faces essentially as well as pictures identical at presentation and test; (b) major changes in the appearance of a face ("disguises") reduced recognition almost to the level of chance; and (c) subjects encoding faces in terms of personality characteristics showed better recognition performance than subjects whose processing was based on physical, facial features. Experiment 2 expanded on result (b), utilizing photographs with systematic variations in pose and in the presence/absence of glasses, wig, and beard. The design required subjects to learn names for target faces and then to identify those targets in a series of test photographs. The manipulation of pose and disguising features produced effects on probability of identification that were orderly and dramatic in magnitude. Simple changes in appearance can effectively interfere with recognition of faces.

Attention↗

Diver performance: the effect of cold.

Fifteen divers performed five tasks in water of temperatures 20 degrees C and 5 degrees C, using standard scuba equipment. A significant deterioration of performance occurred under the colder condition in: simple arithmetic 13%; logical reasoning 17%; word recall 37%; word recognition 11%; and manual dexterity 17%. Throughout each dive, rectal and five skin temperatures were monitored. Average fall in rectal temperature was 0.5 degrees C during 20 degrees C dives and 1.1 degrees C during 5 degrees C dives. Average body surface temperature fell by 5 degrees C and 12.5 degrees C respectively. Average heat losses calculated from the data were 95 kcal.m(-2).hr(-1) (20 degrees C dives) and 245 kcal.m(-2).hr(-1) (5 degrees C dives). The impairment in word recognition was significantly correlated with the fall in rectal temperature for the 5 degrees C dives. For other tests, the deterioration did not appear to be correlated with body-temperature changes, but rather, occurred rapidly upon cold water immersion. The significance of these findings is discussed in relation to current understanding of the mechanisms by which cold is thought to influence performance underwater.

Adaptation, Physiological↗