Performance validity in outpatients with multiple sclerosis and cognitive complaints.

BACKGROUND: Suboptimal performance during neuropsychological assessment renders cognitive test results invalid. However, suboptimal performance has rarely been investigated in multiple sclerosis (MS). OBJECTIVES: To investigate potential underlying mechanisms of suboptimal performance in MS. METHODS: Performance validity testing, neuropsychological assessments, neuroimaging, and questionnaires were analyzed in 99 MS outpatients with cognitive complaints. Based on performance validity testing patients were classified as valid or invalid performers, and based on neuropsychological test results as cognitively impaired or preserved. Group comparisons and correlational analyses were performed on demographics, patient-reported, and disease-related outcomes. RESULTS: Twenty percent displayed invalid performance. Invalid and valid performers did not differ regarding demographic, patient-reported, and disease-related outcomes. Disease severity of invalid and valid performers with cognitive impairment was comparable, but worse than cognitively preserved valid performers. Lower performance validity scores related to lower cognitive functioning, lower education, being male, and higher disability levels (p < 0.05). CONCLUSION: Suboptimal performance frequently occurs in patients with MS and cognitive complaints. In both clinical practice and in cognitive research, suboptimal performance should be considered in the interpretation of cognitive outcomes. Identification of factors that differentiate between suboptimal and optimal performers with cognitive impairment needs further exploration.

Parkinson's patients' executive profile and goals they set for improvement: Why is cognitive rehabilitation not common practice?

Impairments in executive functions (EF) are the core cognitive impairment in patients with Parkinson's disease (PD). Surprisingly, cognitive rehabilitation is not routinely offered to patients with PD. However, in patients with acquired brain injury (ABI), cognitive rehabilitation, in particular strategic executive training, is common practice and has been shown to be effective. In this study, we determined whether PD patients have different needs and aims with regard to strategic executive training than ABI patients, and whether possible differences might be a reason for not offering this kind of cognitive rehabilitation programme to patients with PD. Patients' needs and aims were operationalised by individually set goals, which were classified into domains of EF and daily life. In addition, patients with PD and ABI were compared on their cognitive, in particular EF, profile. Overall, PD patients' goals and cognitive profile were similar to those of patients with ABI. Therefore, based on the findings of this study, there is no reason to assume that strategic executive training cannot be part of standard therapy in PD. However, when strategic executive training is applied in clinical practice, disease-specific characteristics need to be taken into account.

Post-stroke fatigue: a treatment protocol that is being evaluated.

PURPOSE: Post-stroke fatigue is a common and debilitating complaint, which has only recently received attention in clinical rehabilitation. Until now, no evidence-based treatments have been available for the condition. Therefore, a new treatment was designed to reduce post-stroke fatigue complaints: Cognitive and Graded Activity Training (COGRAT). RATIONALE: Following the premise that post-stroke fatigue is primarily caused by brain damage, the treatment aims to prevent fatigue and to manage existing fatigue symptoms. The purpose of the added graded activity programme is to reduce fatigue by changing cognitions and enhancing physical fitness. THEORY INTO PRACTICE: COGRAT consists of a cognitive treatment and graded activity programme in small groups over 12 weeks. In the cognitive treatment, patients receive education on post-stroke fatigue and register their activities and fatigue to gain insight into their daily agenda and fatigability. Patients are then taught several compensation strategies. Cognitive behavioural therapy is used to diminish anxiety, facilitate behavioural change and manage fatigue symptoms. The graded activity programme consists of walking on a treadmill, strength training and home work assignments. Maximum heart rate and strength are increased from 40% at the beginning of the training to a maximum of 70%. CONSIDERATIONS FOR FUTURE IMPROVEMENTS: COGRAT is currently being evaluated in outpatients with severe post-stroke fatigue in a multicentre randomized controlled trial. Preliminary data suggest both positive short- and long-term effects. Adaptations for other neurological patient groups suffering from fatigue are suggested.

Stroop interference and disorders of selective attention.

Fourteen patients with right-hemisphere CVA and 8 patients with a left-hemisphere CVA were examined for selective attention deficits using a variant of the Stroop color-word task: the picture-word interference task. Experiments 1 and 2 first compared the performance of the two patient groups and a control group in three tasks of increasing difficulty: picture-word detection, word reading, and picture naming. The results showed that (a) the two patient groups were significantly slower than the control group, but did not differ from each other, and (b) the difference in mean RT between the two patient groups and the control group did not increase with task difficulty. In Experiment 3, the subjects were required to name pictures while ignoring accompanying distractors: nonletter symbols, unrelated words or semantically related words. In this task, the right hemisphere patients showed a much larger semantic interference effect than both the left hemisphere patients and the control group. It is argued that this finding most probably reflects problems in visual selective attention with the right hemisphere patients.

Visual Scanning Training for Neglect after Stroke with and without a Computerized Lane Tracking Dual Task.

Neglect patients typically fail to explore the contralesional half-space. During visual scanning training, these patients learn to consciously pay attention to contralesional target stimuli. It has been suggested that combining scanning training with methods addressing non-spatial attention might enhance training results. In the present study, a dual task training component was added to a visual scanning training (i.e., Training di Scanning Visuospaziale - TSVS; Pizzamiglio et al., 1990). Twenty-nine subacute right hemisphere stroke patients were semi-randomly assigned to an experimental (N = 14) or a control group (N = 15). Patients received 30 training sessions during 6 weeks. TSVS consisted of four standardized tasks (digit detection, reading/copying, copying drawings, and figure description). Moreover, a driving simulator task was integrated in the training procedure. Control patients practiced a single lane tracking task for 2 days a week during 6 weeks. The experimental group was administered the same training schedule, but in weeks 4-6 of the training, the TSVS digit detection task was combined with lane tracking on the same projection screen, so as to create a dual task (computerized visual reaction time task designed for training). Various neglect tests and driving simulator tasks were administered before and after training. No significant group and interaction effects were found that might reflect additional positive effects of dual task training. Significant improvements after training were observed in both groups taken together on most assessment tasks. Ameliorations were generally not correlated to post-onset time, but spontaneous recovery, test-retest variability, and learning effects could not be ruled out completely, since these were not controlled for. Future research might focus on increasing the amount of dual task training, the implementation of progressive difficulty levels in driving simulator tasks, and further exploration of relationships between dual task training and daily functioning.

Rehabilitation of executive disorders after brain injury: are interventions effective?

In this paper, the effectiveness of interventions for executive disorders was reviewed. The objective was to evaluate the internal and external validity of intervention studies. A total of 46 papers, describing 54 studies, conducted in the last two decades meeting several preset inclusion criteria, was included in this review. The studies were categorized into three treatment approaches in order to enhance comparability. The overall results show that many interventions yield positive outcomes and seem to be effective in reducing executive problems in brain-injured subjects. However, several studies have only an explorative intent and are based on less sophisticated experimental designs. The verification of their results is generally more tenuous. The internal validity, or the set-up of experimental conditions necessary to draw valid conclusions about treatment effectiveness, including the choice of well-matched control groups, or the randomization of patients over treatment and control conditions, is not always strong. The same conclusion can be drawn for the external validity of a number of the intervention studies; often evidence of generalization to real-life situations, long-term follow-up, and transfer to non-trained situations, were (partially) lacking in the studies under review. The authors are aware that the design of proper randomized controlled trials for the investigation of the treatment effectiveness of executive disorders is cumbersome and time consuming. Nonetheless, the provisional results of several well-designed studies described in this review make the effort worthwhile.

Categorization of arithmetic word problems by normals, frontal and posterior-injured patients.

An important stage in the solution of mathematical word problems is the formation of a global internal representation of the problem. There is ample evidence that the recognition of problem schemata or problem types plays a major role in this representation stage. In the present study, a sorting task is used in order to examine the knowledge of arithmetical word-problem schemata in a group of normals, a group of patients with frontal lesions, and a group of patients with left posterior brain lesions. Quantitative and qualitative analyses show that normals classify the word problems according to principles that are essential for problem solving. These analyses also reveal that the general sorting dimensions of the frontal and the left posterior brain-damaged groups, as measured by a multidimensional scaling procedure, are similar. Cluster analysis shows that both groups base their sorting behavior mainly on superficial text characteristics, such as the objects found in the various word problems. The implications of these differences in sorting behavior for arithmetical word-problem solving are discussed.

The internal representation of arithmetical word problem sentences: frontal and posterior-injured patients compared.

Patients with frontal and left posterior brain lesions have severe difficulties in arithmetical word problem solving. In the present study the origin of these difficulties is investigated from an information-processing perspective. Following this perspective the first stage in word problem solving consists of a translation of individual sentences to an internal representation. This translation process is examined in 30 frontal patients, 10 left posterior-injured patients, and 10 healthy controls with a recognition and a sentence-picture matching task. In addition, the relationship between sentence representation and arithmetical word problem solving is studied. The results suggest that error rates in the translation of different types of arithmetical word problem propositions differ substantially in our three groups. A relationship between translation skills and arithmetical word problem solving ability is also found.

Positive behavioural disturbances in the rehabilitation phase after severe traumatic brain injury: an historic cohort study.

PRIMARY OBJECTIVE: To investigate the association of post-traumatic amnesia (PTA) with positive behavioural disturbances (PBD) in an historic cohort of patients with severe traumatic brain injury (TBI) and to evaluate the use and effects of neuroleptic drugs in this cohort. RESEARCH DESIGN: Historic cohort study. METHODS: The medical files of 60 patients with severe TBI, selected for inpatient rehabilitation during a period of 5.5 years, were independently examined for the presence of PTA and PBD at admission in the rehabilitation centre as well as for the concomitant use of neuroleptic drugs. All TBI patients with PBD at admission were subjected to special nursing measures consisting of a structured and safe environment, a minimum number of caregivers and provision of simple and consistent feedback. As a basic policy, the use of neuroleptic medication was minimized or stopped. RESULTS: Of the 28 patients suffering from PTA at admission, 16 demonstrated PBD (positive predictive value 0.57 (95% CI 0.45-0.70)). In contrast, all the 32 patients without PTA but one did not show PBD (negative predictive value 0.97 (95% CI 0.93-1.00)). Seven of the 17 patients with PBD (41%) had been prescribed neuroleptic medication, of whom five patients (81%) experienced undesired side effects. Because of the special nursing measures, these drugs could be stopped or substituted by non-neuroleptic behaviour-modifying drugs in all patients within 3 weeks, without aggravation of their PBD. CONCLUSIONS: These results suggest that impaired attention and memory may play a critical role in the development of PBD in patients with severe TBI. From this perspective, maximum effort must be made to improve TBI patients' level of attention, memory and orientation instead of using mechanical or chemical restraints.

Development of neuropsychiatric symptoms in poststroke patients: a cross-sectional study.

OBJECTIVE: The study aimed to characterize neuropsychiatric symptomatology and its evolution in a large group of poststroke patients during their first year. METHOD: The Neuropsychiatric Inventory (NPI) was administered to a sample of 124 poststroke patients, divided into three independent groups on the basis of time from stroke (2, 6 and 12 months). The controls were 61 healthy subjects. RESULTS: A wide range of neuropsychiatric symptoms was found significant in the poststroke population: mostly depression (61%), irritability (33%), eating disturbances (33%), agitation (28%), apathy (27%) and anxiety (23%). Modifications in terms of greater depression, anxiety, irritability and eating disturbances evolved in the year following stroke. Other symptoms were significantly present depending on time from stroke. Clear relations with other clinical and demographic variables were also found. CONCLUSION: Neuropsychiatric symptoms constitute an important part of comorbidity in stroke patients; thus, suitable assessment tools may improve clinical understanding of these patients.