Biomedical subjects

Bernd Leplow

Publications and source records attributed to Bernd Leplow.

9 recordsLinked to original sources

PubMed2005

Attention and executive functions in remitted major depression patients.

BACKGROUND: Although deficits in attention and executive functions in patients with Major Depressive Disorder (MDD) are well confirmed [Veiel, H.O.F., 1997. A preliminary profile of neuropsychological deficits associated with major depression. Journal of Clinical and Experimental Neuropsychology 19, 587-603.]. The database regarding the relationship between impairments and the duration of disease or the number of episodes is inconsistent. Furthermore, the role of long-term cognitive impairments in MDD during remitted state is not well understood [Elliott, R., 2002. The neuropsychological profile in primary depression. Taylor and Francis, London, pp. 273-293.]. There is consequently a lack of studies accounting for different courses of illness in the euthymic state and considering the influence of possible attentional deficits on executive performance. METHODS: 40 euthymic patients with MDD diagnosis according to DSM-IV (20 patients with 1-2 episodes and 20 severe depressives with at least three episodes) as well as 20 healthy controls matched for education and age were administered three tests for attention (attentional shift, Stroop task, sustained attention) and three for executive functions (BADS, word fluency, memory span). The methods selected were theory based with regard to an involvement of frontal-subcortical networks in MDD, attention, and executive functions, respectively. RESULTS: Euthymic patients with MDD showed deficits in all tests related to attentional and executive functions compared to healthy controls. The patient groups did not differ with regard to attentional performance. Executive functions in severe depressives were more impaired than in mild depressives. LIMITATIONS: Differing performances of the patient groups in the subtests of the executive test battery (BADS) can only be interpreted to a limited extent. CONCLUSIONS: The results support the assumption that deficits in attention and executive functions in MDD show an increase in trait character and executive function during chronic course. Implications for differential diagnosis and cognitive psychotherapy are discussed.

Adult↗

PubMed2005

Only subtle cognitive deficits in non-bulbar amyotrophic lateral sclerosis patients.

Neuropsychological investigations of amyotrophic sclerosis (ALS) patients revealed considerable discrepancies regarding neurocognitive functions. Some, but not all studies have suggested executive dysfunctioning and memory impairment, and there is a wide range of applied neuropsychological tests and results. In this study, we investigated the neuropsychological performance of 15 non-bulbar ALS patients, 14 patients with neuromuscular symptoms, and 15 healthy controls. To avoid confounding effects of motor disability, performance was assessed using exclusively motor-free tests of frontal lobe functioning (specific memory functions, conditional-associative learning, attention, and executive functions). ALS patients exhibited poorer performance in two conditions (semantic and alternating condition, respectively) of the Verbal Fluency Test, suggesting a subtle executive deficit. No deficits were found in tests of memory, conditional-associative learning, or attention. Assessed mood status was not related to neuropsychological performance. Verbal memory (CVLT) and verbal fluency (lexical condition) were positively associated with duration of disease. Our results support the view that there are only subtle cognitive deficits in ALS patients and we assume a possible effect of practice on cognitive tasks following reduced daily motor activity.

Aged↗

PubMed2003

Recovery of spatial memory and persistence of spatial orientation deficits after traumatic brain injury during childhood.

The present study set out to examine the recovery of spatial learning and cognitive mapping skills after severe TBI in childhood. A prospective investigation was carried out with repeated measures. Children with TBI (n = 18) and healthy matched controls (n = 18) were investigated while the children with TBI stayed in a rehabilitation facility (t0) and 4 years later (t1). Children were assessed with the Kiel Locomotor Maze, where they had to remember defined locations in an experimental chamber with completely controlled intra- and extra-maze cues until the learning criterion was reached. During probe trials, cognitive mapping strategies were assessed. Results showed (i) that spatial learning is functionally restituted 4 years post-trauma and (ii) that cognitive mapping skills are still impaired 4 years post-trauma. It was concluded that cognitive performance of children who survived a severe TBI may he overestimated, having far reaching consequences for the children.

Analysis of Variance↗

PubMed2003

The role of locomotion in the acquisition and transfer of spatial knowledge in children.

The role of locomotion in the acquisition and transfer of spatial knowledge was investigated in 144 five-, seven- and eleven-year-old children. Two experiments were conducted in the Kiel locomotor maze. In the first experiment, one group of children explored the spatial layout by walking through the maze, while another learned the maze by surveying the layout. In the second experiment, children were exposed to one of two orientation tests in the maze, one of which could be solved using "landmark orientation", the other only using a "relational place orientation". Children sitting by the side of the experimental chamber surveying the maze needed fewer trials to learn the spatial layout than children exploring the environment in the locomotion condition, but in the orientation test demanding the "relational place orientation" children who had explored the maze in the locomotion condition outperformed the children in the non-locomotion condition. Results are discussed in the context of cognitive mapping models.

Child↗

PubMed2003

Navigational place learning in children and young adults as assessed with a standardized locomotor search task.

Spatial behaviour was investigated using a spatial learning task based on the Radial Arm Maze, the Morris Water Maze, and open-field search-task procedures. Ninety-six healthy children from six age groups (3, 4, 5, 7, 10 and 12 years) with no history of CNS disorders were studied with respect to the emergence of position-, cue- and place responses. Participants were to detect x out of n hidden locations, frames of reference could be varied systematically, and three spatial memory errors and speed of navigation were recorded automatically. Task difficulties were equivalent for each age group. Results showed that navigational place learning was fully developed by the age of 10, whereas participants relied on cue orientation up to age 7. Even in the youngest group, the task could be achieved without relying on egocentric orientation, provided that proximal cues were presented. Most of the errors were of the reference memory type, whereas working memory errors were extremely rare. Speed of navigation markedly improved between age 5 and 7. An additional experiment showed that navigational place-learning behaviour was clearly dependent on distal cues. A third study showed that in young adults, learning of the spatial layout improved, but performance on the place task did not improve any further. No sex differences were observed.

Adolescent↗

PubMed2003

Quantification of human spatial behavior in an open field-locomotor maze.

To obtain and analyze the strategies of human spatial behavior, the Kiel Locomotor Maze, a maze-like analogue, was used. The Kiel Locomotor Maze automatically records different types of spatial memory errors, distances and rotation angles, decision time, and reaction times for each move. 18 patients with cerebral tumors within the frontal, temporal, or parietal lobes and 16 patients with Parkinson's disease were investigated with respect to "sense of direction." These parameters provide information beyond error scores. It was expected that patients with focal cortical lesions would be characterised by loss of directional sense whereas basal ganglia-related brain disease is characterised by preserved directional sense but poor memory for cue-defined target locations. Based on the neuropsychological theory of head-direction sense, especially the 1991 model of McNaughton, the functionality of storage and update of the head-direction sense may be reflected with the help of these parameters. "Direction sense" parameters provide information about success or failure of the acquisition of a spatial task much earlier than error scores.

Adult↗

PubMed2002

Spatial behaviour is driven by proximal cues even in mildly impaired Parkinson's disease.

This investigation addresses the question whether patients with mild to moderate Parkinson's disease (PD) show spatial deficits in real-life settings. Therefore, a "search through"-locomotor task incorporating basic features of both the radial arm maze and the Morris water maze paradigms was used. The participants had to find and remember five out of twenty hidden locations within a completely controlled environment. Different spatial memory errors and inter-response intervals were recorded automatically. Fourteen patients with idiopathic PD and fourteen healthy controls matched for age, sex, handedness, and education were investigated. Patients and controls were widely comparable with respect to intelligence, verbal memory, and executive functions. Results show that performance deteriorated in about half of the patients if the starting position was moved by 90 degrees and the proximal cues were deleted simultaneously. This deficit was systematically related to specific measures of attention. Moreover, patients were less able to update their locomotor strategies towards a more effective strategy. Results are discussed with respect to the patient's inability to generate rules which can be flexibly used in changing environments, especially if proximal cues are removed. It is concluded that deficits in spatial behaviour can be elicited even in near-to-real-life situations if appropriate testing procedures are used.

Adult↗

PubMed2002

Dissociated conditional-associative learning in anorexia nervosa.

This study assessed the acquisition of conditional-associations using neutral and individually threatening nouns in 16 females with anorexia nervosa (AN), 16 females with bulimia nervosa (BN) and 16 normal controls (NC). Groups did not differ in terms of age, sex, handedness, depression, intelligence, verbal memory and verbal fluency measures. Furthermore, patients and controls were widely comparable on any test assessing neuropsychological functioning. In the conditional-associative learning (CAL) task, anorexic patients displayed an impaired performance with neutral material but not with individually threatening material. Such a deficit was not evident in bulimics or in normal controls. Only anorexics showed a dissociation in the CAL of material with different emotional valence. These findings support the assumptions from functional neuroimaging investigations in AN and justify the assignment of this disorder to the obsessive-compulsive spectrum disorders.

Adolescent↗

PubMed2002

Specificity of conditional associative-learning deficits in obsessive-compulsive disorder (OCD) and non-OCD anxiety disorders.

The acquisition of conditional associations using neutral and disease-related nouns was studied in 15 inpatients with obsessive-compulsive disorder (OCD), 15 inpatients with non-OCD anxiety disorders and 15 chronic pain inpatients. Patients were comparable with respect to age, sex, depression, intelligence, executive functions, verbal and spatial memory, visuoconstructive functions, and handedness. The investigation took place in the diagnostic phase prior to the patient's beginning a standardized behavioral treatment program. It was hypothesized that anxiety patients acquired disease-related material faster than pain patients but that only OCD patients show inferior performance with respect to neutral stimuli. Results show that the three patient groups were widely comparable concerning neuropsychological background measures and showed equivalent results with respect to disease-related stimuli. But OCD patients yielded an inferior degree of performance when neutral stimuli were used whereas non-OCD anxiety disorder and pain patients displayed an equivalent degree of performance both for neutral and disease-related material, respectively. Results are discussed within the framework of obsessive-compulsive spectrum disorders.

Adult↗