Zsuzsanna Kerekes

Sensitivity and specificity of Addenbrooke's Cognitive Examination, Mattis Dementia Rating Scale, Frontal Assessment Battery and Mini Mental State Examination for diagnosing dementia in Parkinson's disease

INTRODUCTION Among the non-motor features of Parkinsons disease (PD), cognitive impairment is one of the most troublesome problems. Highly sensitive and specific screening instruments for detecting dementia in PD (PDD) are required in the clinical practice. METHODS In our study we evaluated the sensitivity and specificity of different neuropsychological tests (Addenbrookes Cognitive Examination, ACE; Frontal Assessment Battery, FAB and Mattis Dementia Rating Scale, MDRS) in 73 Parkinsons disease patients without depression. By receiver operating characteristic curve analysis, these screening instruments were tested against the recently established clinical diagnostic criteria of PDD. RESULTS Best cut-off score for ACE to identify PDD was 80 points (sensitivity = 74.0%, specificity = 78.1%). For FAB the most optimal cut-off value was 12 points (sensitivity = 66.3%, specificity = 72.2%); whereas for MDRS it was 125 points (sensitivity = 89.8%, specificity = 98.3%). Among the examined test batteries, MDRS had the best clinicometric profile for detecting PDD. CONCLUSION Although the types of applied screening instruments might differ from movement disorder clinic to clinic within a country, determination of the most specific and sensitive test for the given population remains to be an important task. Our results demonstrated that the specificity and sensitivity of MDRS was better than those of ACE, FAB and MMSE in Hungary. However, further studies with larger sample size and more uniform criteria for participation are required to determine the most suitable screening instrument for cognitive impairment.

Reorganization of Motor System in Parkinson's Disease

Background/Aims: We investigated adaptive reorganization in Parkinson’s disease (PD) by fMRI using a passive movement task and compared the brain activation patterns of 10 patients with left- versus right-sided dominant symptoms. Five healthy controls were also investigated with the same settings. Methods: We grouped patients according to the predominant side of symptoms; thus, a right-sided dominant and a left-sided dominant group was formed. The paradigm consisted of a 4-finger passive movement task, which altered with resting states. For each subject, this examination was performed twice: on the left and on the right hand separately. Results: In healthy controls, motor-related areas contralateral to the moving fingers showed activation on fMRI. Concerning PD patients, motor-related areas of the ipsilateral hemisphere – including the primary motor cortex, supplementary motor area, and basal ganglia – seemed to be involved in the motor reorganization in PD. However, we could only demonstrate this reorganization in patients with right-sided dominant symptoms. Conclusions: We suggest that the human brain in PD tries to compensate for the failure of the basal ganglia motor loop by employing alternative (ipsilateral) motor pathways, indicating that a complex reorganization can also take place in disorders like PD which affect the whole motor-related network.

GENEROSITY, REPUTATION, AND COSTLY SIGNALING: A PRELIMINARY STUDY OF ALTRUISM TOWARD UNFAMILIAR PEOPLE

Generosity seems to be a cross-culturally ubiquitous feature of life. Helping others is considered as a costly act through which the altruists gain popularity and reputation in their refer- ence group and this elevated reputation will pay off for them in future social relationships. This costly signaling theory has been widely tested in pre-industrial societies. Our purpose was to ex- amine if the assumptions of CST are verifiable in modern, industrial societies. Using a complex experimental procedure with four subsequent phases we could examine reputation-gaining in real- istic conditions. We found that more people are willing to offer help to a charity organization when their group mates are aware of their altruistic intention than those whose offer was con- cealed from the rest of the group. In return, the offered charity service increased the altruists reputation in the group; in the light of sociometric surveys they gained more popularity than the others. Finally, it turned out that whereas men are more likely to offer potential help in the pres- ence of others, women provide more actual help.