Alexithymia and apathy in Parkinson's disease: neurocognitive correlates

Non-motor symptoms such as neuropsychiatric and cognitive dysfunction have been found to be common in Parkinson’s disease (PD) but the relation between such symptoms is poorly understood. We focused on alexithymia, an impairment of affective and cognitive emotional processing, as there is evidence for its interaction with cognition in other disorders. Twenty-two non-demented PD patients and 22 matched normal control adults (NC) were administered rating scales assessing neuropsychiatric status, including alexithymia, apathy, and depression, and a series of neuropsychological tests. As expected, PD patients showed more alexithymia than NC, and there was a significant association between alexithymia and disease stage. Alexithymia was associated with performance on non-verbally mediated measures of executive and visuospatial function, but not on verbally mediated tasks. By contrast, there was no correlation between cognition and ratings of either depression or apathy. Our findings demonstrate a distinct association of alexithymia with non-verbal cognition in PD, implicating right hemisphere processes, and differentiate between alexithymia and other neuropsychiatric symptoms in regard to PD cognition.Published versio

Multilevel Clustering Fault Model for IC Manufacture

A hierarchical approach to the construction of compound distributions for process-induced faults in IC manufacture is proposed. Within this framework, the negative binomial distribution is treated as level-1 models. The hierarchical approach to fault distribution offers an integrated picture of how fault density varies from region to region within a wafer, from wafer to wafer within a batch, and so on. A theory of compound-distribution hierarchies is developed by means of generating functions. A study of correlations, which naturally appears in microelectronics due to the batch character of IC manufacture, is proposed. Taking these correlations into account is of significant importance for developing procedures for statistical quality control in IC manufacture. With respect to applications, hierarchies of yield means and yield probability-density functions are considered.Comment: 10 pages, the International Conference "Micro- and Nanoelectronics- 2003" (ICMNE-2003),Zvenigorod, Moscow district, Russia, October 6-10, 200

The role of the teacher in object-level and meta-level learning

The National Curriculum statement, or NCS for short, proposes significant shifts in the way that teachers carry out their work. Strategies, such as investigation and collaborative work were promoted as a reform model for effective teaching and learning. Thus, the intention of this research project is to determine how mathematics teachers are implementing the new reform in South Africa. Based on Sfard’s theory of commognitive development, a theoretical framework has been established and the focus specified in the following research questions: 1. How does a teacher mediate instruction during object-level & meta-level learning? 2. What enables and constrains her/his facilitative mediation in the case of Congruency in Grade 9? 3. What can we learn about the practical efficacy of Sfard’s discourse theory? In order to explore the actual teaching process the research project presents a case study constituted from two teaching practices on one topic, Congruency, at a College in Johannesburg. The purpose of observing and interviewing two teachers on the same lessons is to get a greater variety of conversation on object-level and meta-level learning. At the same time analysing their teaching process in-depth creates an opportunity to have different possibilities of mediating collaborative learning. The study addresses the three research questions through two related activities – non-participant observation and semi-structural interviews with teachers (in order to provide an opportunity for teachers to express their opinion). Two main findings can be summarized: Firstly, the way the teacher manages instruction originates from her/his teaching style. The data analysis clearly confirms that mediation of the two teachers on the topic Congruency does not differ according object-level and meta-level learning, but according to the teachers. The second finding is related with Sfard’s theoretical perspective: on the one hand the Department recommends investigative activities, whilst, on the other hand, Sfards’ theory states that reinvention by the learner is highly unlikely. Therefore the practical efficacy of Sfard’s theory is that in meta-level learning investigative activities are not appropriate and the role of the teacher should be dominant, not necessarily as facilitator. This research study is an empirical proof of the validity of Sfard’s theory and unspecified requirements of the Department of Education. KEYWORDS: object-level learning, meta-level learning, Congruency, Commognitive theory