Depressive deficits in memory: focusing attention improves subsequent recall.

Ss diagnosed as depressed, recovered from depression, or without a history of depression performed an unintentional learning task, followed by tests of free and forced recall. In the learning task, Ss decided whether a series of nouns sensibly completed corresponding sentence frames that varied in decision difficulty. For half of the Ss, the focus of attention was unconstrained by the demands of this task. The others, however, were required to repeat the targeted noun at the end of the trial as a means of focusing their attention on the task. Depressed Ss in the unfocused condition subsequently recalled fewer words than did both control groups, but this deficit disappeared in the focused condition. These results suggest that depression might not fundamentally impair the resources required for good performance on such tasks. The results' relevance to resource-allocation, initiative, and inhibition accounts of depressive deficits in memory is discussed.     

Autobiographical memory deficits in schizophrenia

This study investigated autobiographical memory processes in a group of individuals diagnosed with schizophrenia and matched controls. The schizophrenia group displayed an overgeneral style of autobiographical memory retrieval on two widely used measures, and displayed problems retrieving both autobiographical facts and events. They showed a specific impairment in the recall of autobiographical events and facts in early adulthood, around the time of onset of their illness. Retrieval deficits were independent of mood state and premorbid intellectual functioning. The magnitude of the deficits in autobiographical memory retrieval specificity were considerably greater than any general impairments in episodic and working memory.     

Schizophrenic tendencies and memory deficits in normals

The report tests the hypothesis that normals who exhibit schizophrenic tendencies are likely to show verbal-memory deficits of the types observed in schizophrenics. Thirty-four middle-aged men were tested using the MMPI 2–7–8 schizophrenic-tendency scales, the Sorting Consistency Task and the Physical Anhedonia Scale. The dependent variables were four memory tests selected on the basis of their known discriminating power and their relevance. The results showed the Schizophrenia (8) and Psychasthenia (7) scales of MMPI, and the Sorting Consistency Task effectively detected memory deficits in normals. When partialling out intelligence, as a measure of general current cognitive functioning, it appeared that one of the deficits reflecting encoding difficulty disappeared. This suggests that normal ‘high-risk’ subjects for schizophrenia show a ‘generalized deficit’, which affects memory in addition to a ‘differential deficit’ in retention. Though tentative, the results can be taken as an indication that ‘high-risk’ subjects indeed show memory deficits and that detecting these deficits requires relatively sensitive tools.     

Acute memory deficits in chemotherapy-treated adults

Data from research on amnesia and epilepsy are equivocal with regards to the dissociation, shown in animal models, between rapid and slow long-term memory consolidation. Cancer treatments have lasting disruptive effects on memory and on brain structures associated with memory, but their acute effects on synaptic consolidation are unknown. We investigated the hypothesis that cancer treatment selectively impairs slow synaptic consolidation. Cancer patients and their matched controls were administered a novel list-learning task modelled on the Rey Auditory Verbal Learning Test. Learning, forgetting, and retrieval were tested before, and one day after patients’ first chemotherapy treatment. Due to difficulties recruiting cancer patients at that sensitive time, we were only able to study 10 patients and their matched controls. Patients exhibited treatment-dependent accelerated forgetting over 24 hours compared to their own pre-treatment performance and to the performance of control participants, in agreement with our hypothesis. The number of intrusions increased after treatment, suggesting retrieval deficits. Future research with larger samples should adapt our methods to distinguish between consolidation and retrieval causes for treatment-dependent accelerated forgetting. The presence of significant accelerated forgetting in our small sample is indicative of a potentially large acute effect of chemotherapy treatment on forgetting, with potentially clinically relevant implications.     

Focused attention and depressive deficits in memory.

Hertel and Rude (1991) investigated the effects of depression on memory for words in a sentence completion task. They found that depressive deficits in memory can be eliminated by procedures that increase depressed Ss' focused attention to the task. Three areas are considered in this article: irrelevant thoughts, distraction, and inhibition.     

Recognition memory deficits in mild cognitive impairment

ABSTRACT There is no agreement on the pattern of recognition memory deficits characteristic of patients diagnosed with mild cognitive impairment (MCI). Whereas lower performance in recollection is the hallmark of MCI, there is a strong controversy about possible deficits in familiarity estimates when using recognition memory tasks. The aim of this research is to shed light on the pattern of responding in recollection and familiarity in MCI. Five groups of participants were tested. The main participant samples were those formed by two MCI groups differing in age and an Alzheimer's disease group (AD), which were compared with two control groups. Whereas one of the control groups served to assess the performance of the MCI and AD people, the other one, composed of young healthy participants, served the purpose of evaluating the adequacy of the experimental tasks used in the evaluation of the different components of recognition memory. We used an associative recognition task as a direct index of recollection and a choice task on a pair of stimuli, one of which was perceptually similar to those studied in the associative recognition phase, as an index of familiarity. Our results indicate that recollection decreases with age and neurological status, and familiarity remains stable in the elderly control sample but it is deficient in MCI. This research shows that a unique encoding situation generated deficits in recollective and familiarity mechanisms in mild cognitive impaired individuals, providing evidence for the existence of deficits in both retrieval processes in recognition memory in a MCI stage.     

Overshadowing of subsequent events and recovery thereafter

Four experiments using a conditioned lick suppression preparation with rats were conducted to examine whether overshadowing of subsequent events could be obtained in Pavlovian backward conditioning (i.e. unconditioned stimulus [US] before conditioned stimulus [CS]), and to determine whether such overshadowing could be reversed without further training with the overshadowed CS, as has been reported in overshadowing of antecedent events. In Experiment 1, a backward-conditioned CS overshadowed a second backward-conditioned CS. Two posttraining manipulations, extinction of the overshadowing CS (Experiment 2) and shifting of the temporal relationship of the overshadowing CS to the US (Experiment 3), increased responding to the overshadowed CS. These results constitute the first unambiguous demonstration of stimulus competition between subsequent events using first-order conditioning, and they show that, like overshadowing with forward conditioning, such overshadowing is due, at least in part if not completely, to a failure to express information that had been acquired.     

Pentoxifylline reverses age-related deficits in spatial memory

Pentoxifylline, a phosphodiesterase inhibitor, produces a marked reversal of an age-dependent spatial memory deficit in Fischer 344 strain male rats. Performance of 26-month-old animals treated chronically with pentoxifylline approached that of 3-month-old controls. The effect was not dependent upon concurrent administration of the acetylcholine precursor choline chloride. It is concluded that the pentoxifylline-induced reversal of the age-dependent memory decline is not dependent on any presumed facilitation of acetylation and utilization of exogenously supplied transmitter substrate.     

Recognition memory deficits in mild cognitive impairment

ABSTRACT

There is no agreement on the pattern of recognition memory deficits characteristic of patients diagnosed with mild cognitive impairment (MCI). Whereas lower performance in recollection is the hallmark of MCI, there is a strong controversy about possible deficits in familiarity estimates when using recognition memory tasks. The aim of this research is to shed light on the pattern of responding in recollection and familiarity in MCI. Five groups of participants were tested. The main participant samples were those formed by two MCI groups differing in age and an Alzheimer's disease group (AD), which were compared with two control groups. Whereas one of the control groups served to assess the performance of the MCI and AD people, the other one, composed of young healthy participants, served the purpose of evaluating the adequacy of the experimental tasks used in the evaluation of the different components of recognition memory. We used an associative recognition task as a direct index of recollection and a choice task on a pair of stimuli, one of which was perceptually similar to those studied in the associative recognition phase, as an index of familiarity. Our results indicate that recollection decreases with age and neurological status, and familiarity remains stable in the elderly control sample but it is deficient in MCI. This research shows that a unique encoding situation generated deficits in recollective and familiarity mechanisms in mild cognitive impaired individuals, providing evidence for the existence of deficits in both retrieval processes in recognition memory in a MCI stage.     

Strategic sequence planning and prospective memory impairments in frontally lesioned head trauma patients performing activities of daily living

The aim of this research was to study strategic sequence planning and prospective memory in activities of daily living (ADL) in 10 patients with frontal lobe lesions after a mild to moderate closed head injury (CHI). The lesions were documented radiologically. The CHI patients were compared to 12 normal controls with a neuropsychological test battery and a realistic simulation of complex multitask ADL (planning and preparing a meal). Though the CHI patients were significantly slow on one test and subject to interference on an attention test, they manifested no basic executive or memory deficit on the paper-pencil tests. However, the CHI patients manifested marked anomalies in the organization of behavior in the meal preparation task. While small sequences of actions were easily produced, large action sets could not be correctly executed. An outstanding difficulty in strategic planning and prospective memory, particularly time-based more than event-based, appears to be an important underpinning of the impairment of ADL observed in the CHI patients with frontal lobe lesions.     

Initial codes for order in memory

The roles of positional and associative information in preserving the order of short sequences of items were investigated either by presenting an item in the same serial position on successive trials (position transfer), or by presenting the same pair of items in adjacent but shifted positions on successive trials (association transfer). While Experiment I found that positive transfer of position information occurred after just one repetition of an item in the same serial position, Experiment II found no evidence for association transfer after a single trial. If an item is presented in the same position, or if a pair of items are presented in adjacent positions on several successive trials, position transfer effects built up more rapidly than association transfer effects (Experiments III and IV). However, the rate at which association transfer effects are established depends on the type of item used, with lists of concrete words showing rapid establishment of associations (Experiment V) but lists of digits showing only slow development of associations (Experiment IV). It was concluded that serial order may be preserved both by positional and associative codes, but the establishment of an associative code is linked to the extraction of information about the items themselves.     

Adult age differences in short-term memory and subsequent long-term memory for actions.

Short-term memory for actions was investigated for young adult and elderly adult subjects with the Brown-Peterson procedure at retention intervals of 0 and 15 s. The short-term memory trials were followed by the long-term recall of the prior to-be-remembered actions. The 15-s retention interval was filled either with no activity or with 1 of 3 different interfering activities. Verbal interference had little effect on short-term memory at either age level. Actions performed in the interval either by the subjects or by the experimenter produced significantly lower recall scores at each age level, with the decrement being more pronounced for the elderly than for the young subjects. The long-term memory results indicated that successful short-term recall enhanced later long-term recall, regardless of age level.     

Depressive deficits in memory: processing initiative and resource allocation

Hertel and Hardin investigated the effects of depressed mood states on recognition memory in three experiments. They report that mood effects on memory depend on the subjects' awareness of the task. Four issues are considered in this article: natural and induced moods, processing initiative, initiative versus resource allocation, and strategies.     

Declarative memory deficits and schizophrenia: problems and prospects

Cognitive deficits are among the most important factors leading to poor functional outcomes in schizophrenia, with deficits in declarative memory among the largest and most robust of these. Thus far, attempts to enhance cognition in schizophrenia have shown only modest success, which underlies increasing efforts to develop effective treatment strategies. This review is divided into three main parts. The first section delineates the nature and extent of the deficits in both patients with schizophrenia and in their adult, non-psychotic relatives. The second part focuses on structural and functional abnormalities in the hippocampus, both in people with schizophrenia and in animal studies that model relevant features of the illness. The third section views problems in declarative memory and hippocampal function from the perspective of elevated rates of common medical disorders in schizophrenia, with a focus on insulin insensitivity/diabetes. The likelihood that poor glucose regulation/availability contribute to declarative memory deficits and hippocampal abnormalities is considered, along with the possibility that schizophrenia and poor glucose regulation share common etiologic elements, and with clinical implications of this perspective for enhancing declarative memory.     

Uncontrollability versus perceived failure as determinants of subsequent performance deficits

An experiment is reported that attempted to dissociate the effects of uncontrollability from those of failure in the standard learned helplessness induction procedure involving instrumental tasks. The task was administered to both university and high school students. The primary finding was a grade by controllability interaction, whereby uncontrollability had a larger effect for university students who became much more helpless. Further analysis revealed that while controllability or uncontrollability was the main determinant of university student performance, the performance of the high school students depended primarily upon success or failure. Perhaps we have previously generalized too widely from a restricted subject population.     

Influence of recollection and plausibility on age-related deficits in associative memory

Age-related declines in associative memory are proposed to result from deficits in older adults' ability to recollect the past. The present experiment investigated the ability of older adults to compensate for deficits in recollecting the past by using plausibility. Participants studied a list of word pairs that shared category or rhyme relations. To measure the processes used during the recognition memory test, participants provided self-reported explanations for their memory judgements. Older adults relied primarily on plausibility, and the younger adults relied on both plausibility and recollection. Older adults experienced both positive and negative consequences as a result of using a knowledge-based strategy to compensate for their decreased ability to recollect the past. Specifically, they were just as capable as younger adults at recognising previously studied items and correctly rejecting distractors that were inconsistent with the rule provided at study. However, they falsely recognised distractors that were consistent with that rule more often than younger adults.     

Influence of recollection and plausibility on age-related deficits in associative memory

Age-related declines in associative memory are proposed to result from deficits in older adults’ ability to recollect the past. The present experiment investigated the ability of older adults to compensate for deficits in recollecting the past by using plausibility. Participants studied a list of word pairs that shared category or rhyme relations. To measure the processes used during the recognition memory test, participants provided self-reported explanations for their memory judgements. Older adults relied primarily on plausibility, and the younger adults relied on both plausibility and recollection. Older adults experienced both positive and negative consequences as a result of using a knowledge-based strategy to compensate for their decreased ability to recollect the past. Specifically, they were just as capable as younger adults at recognising previously studied items and correctly rejecting distractors that were inconsistent with the rule provided at study. However, they falsely recognised distractors that were consistent with that rule more often than younger adults.