Rehabilitation of the central executive component of working memory: A re-organisation approach applied to a single case

This paper describes and evaluates a programme of neuropsychological rehabilitation which aims to improve three sub-components of the working memory central executive: processing load, updating and dual-task monitoring, by the acquisition of three re-organisation strategies (double coding, serial processing and speed reduction). Our programme has two stages: cognitive rehabilitation (graduated exercises subdivided into three sub-programmes each corresponding to a sub-component) which enables the patient to acquire the three specific strategies; and an ecological rehabilitation, including analyses of scenarios and simulations of real-life situations, which aims to transfer the strategies learned to everyday life. The programme also includes information meetings. It was applied to a single case who had working memory deficits after a surgical operation for a cerebral tumour on his left internal temporal ganglioglioma. Multiple baseline tests were used to measure the effectiveness of the rehabilitation. The programme proved to be effective for all three working memory components; a generalisation of its effects to everyday life was observed, and the effects were undiminished three months later.     

Cognitive rehabilitation of the updating sub-component of working memory in schizophrenia: a case study

Working memory problems have been identified as a core cognitive deficit in schizophrenia. In this paper, we present the results of a cognitive rehabilitation programme (Duval & Coyette, 2005) administered to a schizophrenia patient, and specifically designed to improve the updating sub-component of working memory. The original feature of this programme was that it involved two types of updating exercises: cognitive and ecological. The purpose was to enable the patient to acquire cognitive strategies that alleviate the mental load of the central executive and to transfer them to daily life. The specificity and efficacy of the programme were assessed with multiple (cognitive, ecological and non-target) baseline measurements. In addition, several questionnaires were administered to assess the effect of the programme on subjective cognitive complaints affecting daily life, psychiatric symptoms and self-esteem. The results demonstrated the efficacy of the rehabilitation programme on the updating function and the generalisation of these beneficial effects to daily life. A significant decrease in both subjective cognitive complaints and psychiatric symptoms was also observed. However, the patient's self-esteem did not improve.     

Rehabilitation of everyday memory deficits in paediatric brain injury: Self-instruction and diary training

Memory problems that interfere with everyday living are frequently reported in children who have sustained acquired brain injury (ABI), but their nature and rehabilitation is under-researched. This study aimed to (1) determine neuropsychological correlates of everyday memory deficits in children with ABI, and (2) investigate the effectiveness of a newly developed programme for their rehabilitation. We assessed everyday memory, verbal memory, attention and behaviour in 15 children with ABI. The children attended the everyday memory rehabilitation programme: six weekly sessions that involved diary training, self-instruction training and case examples. At the onset we found that everyday memory problems were related to impaired attention and behavioural difficulties. On completion of the programme there was a significant increase in children's abilities to perform daily routines that demanded recall of information and events. In addition, children used diaries more frequently. Moreover, significant secondary gains were found in attention and mood (anxiety and depression). In conclusion, the results provided preliminary evidence that our six week programme could be effective in reducing everyday memory difficulties and improving psychological well-being in children with ABI.     

Memory rehabilitation and brain training for surgical temporal lobe epilepsy patients: a preliminary report

The short term impact of a memory rehabilitation programme on verbal memory test performance and subjective ratings of memory in everyday life was assessed in healthy controls and left temporal lobe epilepsy (LTLE) surgical patients. The intervention involved training in the use of external and internal memory support strategies. Half of the sample in addition undertook computerised brain training exercises as homework. LTLE patients were seen either before surgery or 3-6 months after their operation. Improvements in verbal memory were observed in both groups. An effect of brain training was recorded but this did not occur in a consistent direction. Subjective ratings of memory indicated improvements that were significant for the LTLE group but not the controls. Positive changes in the memory outcome measures were associated with improvements in mood. Pre-operative memory rehabilitation was not associated with better outcomes than post-operative intervention. Further research is needed to explore the persistence of the changes observed and to explore if pre-operative rehabilitation offsets post-operative memory decline.     

Rehabilitation of everyday memory deficits in paediatric brain injury: self-instruction and diary training

Memory problems that interfere with everyday living are frequently reported in children who have sustained acquired brain injury (ABI), but their nature and rehabilitation is under-researched. This study aimed to (1) determine neuropsychological correlates of everyday memory deficits in children with ABI, and (2) investigate the effectiveness of a newly developed programme for their rehabilitation. We assessed everyday memory, verbal memory, attention and behaviour in 15 children with ABI. The children attended the everyday memory rehabilitation programme: six weekly sessions that involved diary training, self-instruction training and case examples. At the onset we found that everyday memory problems were related to impaired attention and behavioural difficulties. On completion of the programme there was a significant increase in children's abilities to perform daily routines that demanded recall of information and events. In addition, children used diaries more frequently. Moreover, significant secondary gains were found in attention and mood (anxiety and depression). In conclusion, the results provided preliminary evidence that our six week programme could be effective in reducing everyday memory difficulties and improving psychological well-being in children with ABI.     

Modularity in rehabilitation of working memory: A single-case study

The objective of the present study was to assess the specificity of rehabilitation on different subdomains of working memory. A 38-year-old female with chronic (4?years) stroke suffered from an impairment of the three subdomains of working memory (modality-specific storage systems for verbal and visuo-spatial information and the central executive). She was given an experimental rehabilitation programme, using a multiple-baseline across behaviour design. After two baseline measures three months apart, the first training stage focused on the phonological loop, the second on the visuo-spatial sketchpad, and the third on central executive functions. Verbal aspects of working memory improved significantly after the first training stage, while visuo-spatial tests improved after the second training stage. Central executive functions improved mainly after the third training stage. Modularity effects were not as pronounced for less specific ecological outcome measures, such as the Working Memory Questionnaire, which improved throughout the trial, irrespective of the training condition. This case study suggests that there are both domain-specific and generalisation effects in rehabilitation of working memory, and that rehabilitation should be adapted and tailored to each individual patient's impairments.     

Memory rehabilitation for the working memory of patients with multiple sclerosis (MS)

Objective: The main cognitive impairments in multiple sclerosis (MS) affect the working memory, processing speed, and performances that are in close interaction with one another. Cognitive problems in MS are influenced to a lesser degree by disease recovery medications or treatments,but cognitive rehabilitation is considered one of the promising methods for cure. There is evidence regarding the effectiveness of cognitive rehabilitation for MS patients in various stages of the disease. Since the impairment in working memory is one of the main MS deficits, a particular training that affects this cognitive domain can be of a great value. This study aims to determine the effectiveness of memory rehabilitation on the working memory performance of MS patients.

Method: Sixty MS patients with cognitive impairment and similar in terms of demographic characteristics, duration of disease, neurological problems, and mental health were randomly assigned to three groups: namely, experimental, placebo, and control. Patients’ cognitive evaluation incorporated baseline assessments immediately post-intervention and 5 weeks post-intervention. The experimental group received a cognitive rehabilitation program in one-hour sessions on a weekly basis for 8 weeks. The placebo group received relaxation techniques on a weekly basis; the control group received no intervention.

Results: The results of this study showed that the cognitive rehabilitation program had a positive effect on the working memory performance of patients with MS in the experimental group. These results were achieved in immediate evaluation (post-test) and follow-up 5 weeks after intervention. There was no significant difference in working memory performance between the placebo group and the control group.

Conclusions: According to the study, there is evidence for the effectiveness of a memory rehabilitation program for the working memory of patients with MS. Cognitive rehabilitation can improve working memory disorders and have a positive effect on the working memory performance of these patients.     

The impact of work-related rehabilitation on the quality of life of patients with schizophrenia

In a cross-sectional study of 60 outpatients with schizophrenia (mean age 36.3 ± 11.1) the effect of a work-related rehabilitation programme on the patients' quality of life was investigated. A group of patients with the same diagnosis, but without rehabilitation, served as controls. Patients of the rehabilitation group had been attending the programme for a mean duration of 15.0 months. The programme focuses on occupational and everyday skills and also involves social aspects. The patients' quality of life was assessed using two self-administered questionnaires: the Munich List of Life Dimensions (MLDL, Heinisch et al. 1991) and the Everyday Life Questionnaire (Bullinger et al. 1993). Life satisfaction as well as functional quality of life were higher in the rehabilitation group in the majority of domains assessed. Difference between groups was highest for satisfaction with work, followed by leisure-time activities, independence and friendships/acquaintances. Results indicate that the rehabilitation programme acts like a “lever” which, applied to one point (work, day structuring), subsequently affects most domains of daily living. Accepted: 26 February 1998     

Intellectual functioning and memory deficits in schizophrenia

BACKGROUND: There is converging evidence about the existence of different subgroups of patients with schizophrenia in relation to intellectual ability (intelligence quotient [IQ]). Studying cognitive deficits in such patients in relation to IQ, and more specifically to memory, could help determine the patterns of preserved and impaired functioning in cognitive abilities in association with patterns of preserved and compromised intellect. This information could serve to delimit the possibilities of treatment and rehabilitation in those patients. METHODS: A total of 44 patients with schizophrenia completed a cognitive battery that included executive functioning, attention, speed of information processing, working memory, explicit memory, implicit memory, and everyday memory. Their IQ was also measured to identify 2 subgroups with an IQ of 85 as the cutoff point. Then, differences between the groups in the neurocognitive measures were studied. RESULTS: Performance in executive functioning, attention, working memory, and everyday memory, but not that in speed of information processing, explicit memory, and implicit memory, was associated with intellectual functioning. Patients performed at the same level in perceptual implicit memory but at a lower level in conceptual implicit memory as did healthy control subjects. DISCUSSION: Cognitive deficits in schizophrenia are associated with intellectual functioning. Implicit memory should not be considered as a unique entity. It is suggested that conceptual implicit memory deficit may be a core feature of schizophrenia.     

Prospective memory rehabilitation based on visual imagery techniques

Despite the frequency of prospective memory (PM) problems in the traumatic brain injury (TBI) population, there are only a few rehabilitation programmes that have been specifically designed to address this issue, other than those using?external compensatory strategies. In the present study, a PM rehabilitation programme based on visual imagery techniques expected to strengthen the cue-action association was developed. Ten moderate to severe chronic TBI patients learned to create a mental image representing the association between a prospective cue and an intended action within progressively more complex and naturalistic PM tasks. We hypothesised that compared to TBI patients (n?=?20) who received a short session of education (control condition), TBI patients in the rehabilitation group would exhibit a greater improvement on the event-based than on the time-based condition of a PM ecological task. Results revealed however that this programme was similarly beneficial for both conditions. TBI patients in the rehabilitation group and their relatives also reported less everyday PM failures following the programme, which suggests generalisation. The PM improvement appears to be specific since results on cognitive control tasks remained similar. Therefore, visual imagery techniques appear to improve PM functioning by strengthening the memory trace of the intentions and inducing an automatic recall of the intentions.     

Imagery mnemonics for the rehabilitation of memory: A randomised group controlled trial

Apart from a few, encouraging, single-case studies, evidence of imagery-based mnemonics for the rehabilitation of memory in brain-damaged individuals is sparse. The literature suggests that if imagery is of any use, then it should be applied to mildly memory impaired patients, the learning process should be tailored and a direct transfer training to individual memory problems should be implemented into the training. We compared the outcome of such a programme (nine memory impaired patients) with other approaches to the rehabilitation of memory used in participating centres (12 memory impaired patients). After 4 weeks of baseline and a repeated test battery patients received 30 single sessions of therapy in 10 weeks. Results suggest that imagery training significantly improves delayed recall of everyday relevant verbal materials (stories, appointments). Frequency of memory problems observed by relatives is reduced and each of these effects is stable at 3-month follow-up. This study suggests that a simple imagery technique can improve relevant aspects of everyday verbal memory performance.     

Cognitive rehabilitation in the elderly: effects on memory.

This study reports the effects of a 12-week multimodular cognitive rehabilitation training program on memory performance in two groups of older adults. In the Memory Training module, participants were instructed on the nature of memory and how to improve memory performance; internal and external strategies were described and practiced over the training sessions. Memory performance was assessed by four tests: Alpha Span, Brown-Peterson, Hopkins Verbal Learning Test - Revised (HVLT-R), and Logical Stories. One group received training on entry into the study (Early Training Group, ETG), the other after a 3-month delay (Late Training Group, LTG). The results showed no training-related improvement in working memory (Alpha Span), primary memory (Brown-Peterson, HVLT-R), or recognition memory (HVLT-R). While the most direct analyses of a training effect (analyses of covariance) rarely demonstrated significant effects, exploratory analyses provided some evidence for a training benefit in several measures of secondary memory (Logical Stories; HVLT-R) and strategic processing (Brown-Peterson; Logical Stories; HVLT-R). Positive results were largely restricted to the ETG, possibly because the LTG lost motivation as a consequence of their delayed training. The results need to be treated with caution, but are promising for the rehabilitation of memory functioning in older adults.     

Predictors of change in life skills in schizophrenia after cognitive remediation

Few studies have investigated predictors of response to cognitive remediation interventions in patients with schizophrenia. Predictor studies to date have selected treatment outcome measures that were either part of the remediation intervention itself or closely linked to the intervention with few studies investigating factors that predict generalization to measures of everyday life-skills as an index of treatment-related improvement. In the current study we investigated the relationship between four measures of neurocognitive function, crystallized verbal ability, auditory sustained attention and working memory, verbal learning and memory, and problem-solving, two measures of symptoms, total positive and negative symptoms, and the process variables of treatment intensity and duration, to change on a performance-based measure of everyday life-skills after a year of computer-assisted cognitive remediation offered as part of intensive outpatient rehabilitation treatment. Thirty-six patients with schizophrenia or schizoaffective disorder were studied. Results of a linear regression model revealed that auditory attention and working memory predicted a significant amount of the variance in change in performance-based measures of everyday life skills after cognitive remediation, even when variance for all other neurocognitive variables in the model was controlled. Stepwise regression revealed that auditory attention and working memory predicted change in everyday life-skills across the trial even when baseline life-skill scores, symptoms and treatment process variables were controlled. These findings emphasize the importance of sustained auditory attention and working memory for benefiting from extended programs of cognitive remediation.     

Memory rehabilitation - recent developments and future directions

Memory impairment is a frequent effect of different forms of brain injuries and may be even more handicapping than severe physical problems. The purpose of this article is to critically review empirical studies on the effectiveness of different procedures of memory rehabilitation. Traditionally memory rehabilitation has focused on direct training of memory functioning. The problem of these programs is that training effects hardly generalize to patients' everyday life memory problems. As a consequence of this transfer problem, strategies have been developed (method of vanishing cues, errorless learning) which are restricted to the aim of teaching patients domain specific knowledge. Another aspect of memory rehabilitation concentrates on coping with memory impairment. This may be done by alleviating demands on the patient and by including external resources into the process of recovery. On the other hand, teaching the patient to actively cope with memory related difficulties, has recently become an essential objective of memory rehabilitation. In order to pursue this aim, traditional mnemonic techniques are embedded into training of problem solving abilities and metamemory knowledge. Future perspectives and questions open to research are outlined for each of the different procedures.     

Changing everyday memory behaviour in amnestic mild cognitive impairment: a randomised controlled trial

One of the defining differences between mild cognitive impairment (MCI) and dementia is the degree of independence in everyday activities. Effecting memory-related behavioural change in MCI could help maintain daily function and prolong the time before onset of dependency. However, it is well known that changing previously well-established behaviours is difficult to achieve. We conducted a randomised controlled trial to evaluate the effectiveness of a multidisciplinary group-based intervention programme in changing everyday memory behaviour in individuals with amnestic MCI. The intervention provided evidenced-based memory training and lifestyle education to optimise memory behaviour. Fifty-four participants were randomly assigned to treatment or waitlist-control conditions. Consistent with our primary goal, treatment participants showed an increase in memory-strategy knowledge and use from pre-test to immediate post-test, and these gains were maintained at three-month post-test relative to waitlist controls. There were no group differences in memory beliefs or on laboratory tests of objective memory performance. The increase in memory-strategy knowledge and use was associated with the degree of participation in the programme. Individuals with MCI, therefore, can acquire and maintain knowledge about memory strategies and, importantly, can change their everyday memory behaviour by putting this knowledge into practice. This incorporation of practical memory strategies into daily routines could potentially provide the means for maintaining functional independence by individuals with MCI, an issue to be addressed in future research.     

Symptoms versus neurocognition as predictors of change in life skills in schizophrenia after outpatient rehabilitation

A growing body of literature has shown that neurocognitive deficits in schizophrenia account for 20-60% of the variance in measures of outcome, and in many studies are more closely related to outcome than symptoms [Green, M.F., Kern, R.S., Braff, D.L., Mintz, J., 2000. Neurocognitive deficits and functional outcome in schizophrenia: are we measuring the "right stuff"? Schizophr. Bull. 26(1), 119-136; Green, M.F., Kern, R.S., Heaton, R.K., 2004. Longitudinal studies of cognition and functional outcome in schizophrenia: implications for MATRICS. Schizophr. Res. 72(1), 41-51]. Most of these studies have been cross-sectional, few longitudinal studies have investigated the degree to which neurocognition and symptoms predict ability to benefit from outpatient rehabilitation, and no longitudinal studies use measures of everyday life skills that are performance-based. In the current study we investigated the relationship between five measures of neurocognitive function, crystallized verbal ability, visual sustained vigilance, verbal learning, problem-solving, and processing speed, and two measures of symptoms, total positive and negative symptoms, and change on a performance-based measure of everyday life skills after a year of outpatient rehabilitation. Rehabilitation consisted of both psychosocial and cognitive interventions. Forty-six patients with schizophrenia or schizoaffective disorder were studied. Results of a linear regression model revealed that verbal learning predicted a significant amount of the variance in change in performance-based measures of everyday life skills after outpatient rehabilitation, even when variance for all other variables in the model was accounted for. Measures of crystallized verbal ability, sustained visual vigilance, problem-solving, processing speed and symptoms were not linked to functional status change. These findings emphasize the importance of verbal learning for benefiting from psychosocial and cognitive rehabilitation interventions, and suggest the development of alternative rehabilitation strategies for those who do not benefit.     

Cognitive Training for Memory Deficits in Stroke Patients

This study was set up to evaluate the efficacy of a memory training programme in a group of stroke patients. Berg, Koning-Haanstra, and Deelman (1991) developed a training procedure which successfully improved the memory performance of a group of closed head injury patients. The training programme consists of six simple memory strategies, which are applied to daily memory problems that are selected with the patient. Two groups of stroke patients with demonstrable memory deficits were randomly assigned to the training programme or a non-specific training programme involving repetitive practice on memory tasks. After a four week training period retesting showed a significant improvement of the trained memory skills, but there was no improvement on control memory tasks. Subjective ratings of everyday memory functioning did not differ between the two groups.     

A feasibility study of working memory training for individuals with paediatric-onset multiple sclerosis

Objective: To investigate the feasibility and experiences of paediatric-onset multiple sclerosis (MS) patients completing a working memory training programme.

Methods: Nine paediatric-onset MS patients (mean age 19.3?±?4.1 years) identified as having attention and/or working memory difficulties underwent a five-week (five days/week) internet-based working memory training programme (Cogmed?); weekly coaching was provided. Measures of adherence and tolerance were used to establish the feasibility of implementing computerised cognitive training. Qualitative experiences reported by the patients were analysed and factors that may modulate the effects of training were explored.

Results: Six of the nine enrolled patients completed the programme within the recommended time, and all individuals, with the exception of one, were considered to tolerate the training well. Eight of the nine participants acknowledged that training was helpful in one or more ways. All but one participant reported improvements in working memory, although evidence for improvement on objective neuropsychological testing was limited. Lower normalised brain volume emerged as a potentially important variable in predicting extent of improvement on the training programme.

Conclusion: Selected paediatric-onset MS patients can tolerate and complete an intensive cognitive rehabilitation programme. Future investigation of moderators of training effects and the stability of the findings over time is needed.     

Neuropsychological predictors of everyday functioning in adults with intellectual disabilities

Background Very little is known about the neuropsychological correlates of adaptive functioning in people with intellectual disabilities (ID). This study examined whether specific cognitive deficits and demographic variables predicted everyday functioning in adults with ID. Method People with ID (n = 101; ages 19–41 years; mean education = 11 years; 34% women; 54% competitively employed; 41% with mild ID) completed a comprehensive neuropsychological battery grouped into four cognitive domains: processing speed, verbal memory and comprehension, visual perception/constructive function, and executive function. In addition, parents completed an 89‐item rating scale developed to assess a wide range of independent living skills. Results Confirmatory factor analysis results confirmed a correlated four‐factor model of cognitive function and a unidimensional model of everyday functioning. Furthermore, structural equation modelling results supported the predictive relationship of verbal memory/comprehension and employment status (standardized regression coefficients 0.45, 0.22, P ≤ 0.01 for each) to measures of everyday functioning. The two variables together explained 35% of the variance in everyday functioning. Conclusions Both general cognitive dysfunction and specific verbal memory and comprehension deficit impair daily functions in people with ID. These findings have implications for predictive models of adaptive functioning, and for cognitive rehabilitation and deficit compensation strategies for this group.     

Computer-assisted memory retraining of patients with multiple sclerosis

This study aimed to assess the efficacy and specificity of direct computer-assisted memory retraining (CR) in MS patients, in comparison to non-specific retraining, while controlling for severity of impairment, psychiatric symptoms and retest effects. Sixty patients with definite MS and a stable clinical condition were selected. All were assessed neuropsychologically and divided into three matched groups. One group received an 8-week specific CR programme (SCRP) and another received a non-specific 8-week CR programme (NCRP) to retrain attention; a third (control) group received no treatment. After the programmes were completed, all patients were reexamined with the same test battery. Patients were impaired on all 11 memory and attention tests at baseline. Those who received SCRP improved on 7 memory outcome measures, compared to only 1 in the NCRP group and none in the control group. Attention training had no significant effect on relevant outcome measures. Some non-retrained patients showed deterioration of cognitive performance at retest. These results indicate that direct memory training in MS patients is effective in the short-term and is specific. In selected cases, benefits extended to everyday life activities.