No abstract

It is debated how language and praxis are co-represented in the left hemisphere (LH). As voxel-based lesion-symptom mapping in LH stroke patients with aphasia and/or apraxia may contribute to this debate, we here investigated the relationship between language and praxis deficits at the behavioral and lesion levels in 50 sub-acute stroke patients. We hypothesized that language and (meaningful) action are linked via semantic processing in Broca's region. Behaviorally, half of the patients suffered from co-morbid aphasia and apraxia. While 24% (n = 12) of all patients exhibited aphasia without apraxia, apraxia without aphasia was rare (n = 2, 4%). Left inferior frontal, insular, inferior parietal, and superior temporal lesions were specifically associated with deficits in naming, reading, writing, or auditory comprehension. In contrast, lesions affecting the left inferior frontal gyrus, premotor cortex, and the central region as well as the inferior parietal lobe were associated with apraxic deficits (i.e., pantomime, imitation of meaningful and meaningless gestures). Thus, contrary to the predictions of the embodied cognition theory, lesions to sensorimotor and premotor areas were associated with the severity of praxis but not language deficits. Lesions of Brodmann area (BA) 44 led to combined apraxic and aphasic deficits. Data suggest that BA 44 acts as an interface between language and (meaningful) action thereby supporting parcellation schemes (based on connectivity and receptor mapping) which revealed a BA 44 sub-area involved in semantic processing.

Introduction:Cognitive training (CT) has been reported to improve cognition in older adults. Its combination with protective factors such as physical activity (CPT) has rarely been studied, but it has been suggested that CPT might show stronger effects than pure CT. Materials and methods: Healthy older adults (aged 50-85 years) were trained with CPT (n=15) or CT (n=15). Interventions were conducted in 90-minute sessions twice weekly for 6.5 weeks. Cognitive functions were assessed before and immediately after the interventions, and at 1-year follow-up. Results: The main finding was an interaction effect on attention, with comparable gains from CPT and CT from pre-to post-test, but stronger effects of CPT to follow-up (P=0.02). Significant effects were found in subjects in terms of cognitive state (P=0.02), letter verbal fluency (P=0.00), and immediate (P=0.00) and delayed (P=0.01) verbal memory. Post hoc analyses indicated that these latter domains were affected differentially by CPT and CT. No significant between-subject effects were found. Conclusion: Our results suggest that CPT might lead to stronger long-term effects on attention. However, as the difference between CT and CPT was only evident at follow-up, these effects cannot be interpreted as a direct consequence of CPT; they may have been related to sustained physical activity after the training. Other domains were improved by both interventions, but no typical pattern could be identified. Possible underlying mechanisms are discussed, and directions for future research are suggested.

This study gives evidence that cognitive training may be effective to prevent cognitive decline and onset of MCI in PD patients.

The DemTect, a frequently used cognitive screening tool for the German-speaking population, has been proven to be age-, but not education-dependent. To date, scoring routines for persons under and over 60 years of age have been available. In order to describe the age-effect more specifically, the DemTect was administered to persons under 40 (n = 105; median 33 years [18 - 39]) and over 80 years of age [n = 68; median 83 years [80 - 93}). After transformation of the raw scores, which are based on the mean and standard deviation of the respective reference group, an adequate attribution of scores could be achieved and no differences between the groups can be observed in the total score or the subtest scores. The median of the transformed total score was 16 [5 – 18] for the younger and 15 [5 – 18] for the older age group. The new scoring routines supplement the scoring procedures of the DemTect for these age groups.

Cognitive training has been shown to be effective in improving cognitive functions in patients with Mild Cognitive Impairment (MCI). However, data on factors that may influence training gains including sociodemographic variables such as sex or age is rare. In this study, the impact of sex on cognitive training effects was examined in N = 32 age- and education-matched female (n = 16) and male (n = 16) amnestic MCI patients (total sample: age M = 74.97, SD = 5.21; education M = 13.50, SD = 3.11). Patients participated in a six-week multidomain cognitive training program including 12 sessions each 90 min twice weekly in mixed groups with both women and men. Various cognitive domains were assessed before and after the intervention. Despite comparable baseline performance in women and men, we found significant interaction effects Time × Sex in immediate (p = .04) and delayed verbal episodic memory (p= .045) as well as in working memory (p = .042) favoring the female MCI patients. In contrast, the overall analyses with the total sample did not reveal any significant within-subject effects Time. In conclusion, our results give preliminary evidence for stronger cognitive training improvements of female compared to male MCI patients. More generally, they emphasize the importance of sex-sensitive evaluations of cognitive training effects. Possible underlying mechanisms of the found sex differences are discussed and directions for future research are given.

While visuospatial deficits are well-characterized cognitive sequelae of right hemisphere (RH) stroke, apraxic deficits in RH stroke remain poorly understood. Likewise, very little is known about the association between apraxic and visuospatial deficits in RH stroke or about the putative common or differential pathophysiology underlying these deficits. Therefore, we examined the behavioural and lesion patterns of apraxic deficits (pantomime of object use and bucco-facial imitation) and visuospatial deficits (line bisection and letter cancellation tasks) in 50 sub-acute RH stroke patients. Using principal component analysis (PCA), we characterized the relationship between the two deficits. We hypothesized that any interaction of these neuropsychological measures may be influenced by the demands of ego-centric/space-based and/or allo-centric/object-based processing. Contralesional visuospatial deficits were common in our clinically representative patient sample, affecting more than half of RH stroke patients. Furthermore, about one-third of all patients demonstrated apraxic deficits. PCA revealed that pantomiming and the imitation of bucco-facial gestures loaded clearly on a first component (PCA1), while letter cancellation loaded heavily on a second component (PCA2). For line bisection, overall mean deviation loaded on PCA1, while the difference between the mean deviations in contra-versus ipsilesional space loaded on PCA2. These results suggest that PCA1 represents allo-centric/object-based processing and PCA2 ego-centric/space-based processing. This interpretation was corroborated by the statistical lesion analyses with the component scores. Data suggest that disturbed allocentric/object-based processing contributes to apraxic pantomime and imitation deficits in (sub-acute) RH stroke.Apraxia is a cognitive motor disorder impairing imitation and (pantomiming) the use of objects. Since apraxia is (1) most often observed after lesions to the left hemisphere (LH; Dovern, Fink, & Weiss, 2012) and (2) considered to be the classical cognitive disorder along with aphasia in LH stroke patients (Weiss et al., 2016), apraxia research traditionally focuses on apraxic deficits and their neural underpinnings after LH damage.

Stroke-induced neuropsychological sequelae are frequent and highly relevant for the patient's prognosis, so that their diagnostic assessment at an early point in time is highly advisable to allow for the initiation of appropriate treatment. Because stroke patients in the acute and sub-acute phase of a stroke often show a general slowing and restricted resilience, investigation may be limited and is often only manageable by means of instruments that can be used at bedside. Preferably such neuropsychological tests should also be normalised for the target group. An overview of the neuropsychological instruments available in German, which were developed for or applied to stroke patients in the early phases of stroke and rehabilitation, is provided here. One of the nine instruments presented is the newly developed Cologne Neuropsychological Screening for Stroke Patients (German: Kölner Neuropsychologisches Screening für Schlaganfall-Patienten), which is introduced here. The instruments differ in form of investigation, duration, material volume and standardisation. The choice of a particular instrument in a given clinical or scientific context explicitly depends on the diagnostic goal as well as the resilience of the patient.