J.H.L. van den Bercken

Assessing Rational and Intuitive Thinking Styles

Theories of dual cognition assume two distinguishable information processing styles: rational and intuitive. We discuss how the concepts of rationality and intuition are used in these theories, and the relations of these two thinking styles to personality character- istics. With the Rational-Experiential Inventory (REI; Pacini & Epstein, 1999), a questionnaire that assesses personal preferences for thinking either rationally or intuitively, we found clear evidence for the independence of the two thinking styles in a large Dutch sample (N = 774). We also found Conscientiousness to be a significant predictor of a preference for rational thinking and an inverse predictor of intuitive thinking. We also administered the REI and a Big Five inventory to a Spanish sample (N = 141), and present these results next to those of the Dutch sample. We further established the validity of the REIs distinction between rationality and intuition by administering another measure, the Preference for Intuition or Deliberation (PID; Betsch, 2004, 2008), to a subset of the Dutch sample (n = 405). We briefly describe two small studies in which a preference for rationality or intuition, measured by the REI, was found to be related to task behavior. In the general discussion we consider all results together, and compare them to Pacini and Epsteins results. We conclude that a dual-process distinction between rationality and intuition is valid cross-culturally and that a proclivity toward either is reliably measured by the REI, not only in the USA but in Europe as well.

Bimanual simultaneous motor performance and impaired ability to shift attention in Parkinson's disease.

The ability to share time and to shift attention between bimanual simultaneous motor tasks were studied in 18 patients with Parkinsons disease (PD) and 19 age- and intelligence-matched controls. The task consisted of drawing triangles with the dominant hand and squeezing a rubber bulb with the nondominant hand. Motor performance was measured using the variables: amplitude of squeezing, frequency of squeezing and velocity of drawing triangles. After eliminating variance due to baseline differences in single-handed performance, the bimanual simultaneous performance of PD and controls turned out to be similar to the frequency of squeezing and the velocity of drawing triangles. The amplitude of squeezing, however, differed between the two groups: it was significantly reduced in PD. Arguably the disturbance in the bimanual performance of PD patients was not due to a disorder of time sharing, but to a decreased ability to shift attention from the visually cued task to the non visually cued task. The results agree with current evidence that PD patients are more impaired when they have to rely upon internal control for the regulation of shifting attention than when external cues are available.

Haloperidol and cognitive shifting

In this study haloperidol appeared to affect the performance on a selected category of cognitive tasks considered to represent shifting aptitude. A pretest--post-test design was used with two groups of subjects: 17 patients suffering from idiopathic spasmodic torticollis, and 17 controls who were matched for age and intelligence. The results are discussed in relation to previous findings on haloperidol and cognition, shifting disorder in Parkinsons disease and changes in behavioural organization found in animals with an experimentally induced dopaminergic hypoactivity.

Basal Ganglia and Switching Motor Programs

Recently we have introduced a new frame of reference in the search for “rules of order” in the cerebral organization of behavior (Cools and van den Bercken, 1977; Cools, 1981). The cornerstone of this frame is Powers’ definition of behavior: behavior is the control of the input of the organism. By this definition, behavior is conceived of as a process by which the organization inside the organism controls its input; the brain is thereby seen as a hierarchy of negative feedback systems controlling this input (Powers, 1973). It is this concept that allows us to describe how information sent downstream in the hierarchy is successively transformed at each level by adding more and more details about the behavior to be executed.

Information-statistical analysis of social interaction and communication: An analysis-of-variance approach

Abstract Using informational statistics, an analysis-of-variance model is developed for separating the exclusive effects of two simultaneously present factors on the variability of the ongoing behaviour of a reference subject. In particular the following factors are considered: the preceding behaviour of the reference subject itself and the preceding behaviour of its partner. Effects due to the latter are usually regarded as representing communication. The model is compared with other information-statistical models for social interaction proposed in ethological research. Three properties are discussed: structural complexity, the rationale for identifying relevant effects and the efficiency in measuring them. With respect to measuring communication it is shown that several existing models confounded inter-individual and intra-individual effects in behaviour sequences. It is pointed out that different analytical frameworks (e.g. Markovian stochastic processes or analysis-of-variance) can use the same information-statistical formalism but give rise to different interpretations. Finally, the relation between the complexity of inter- and intra-individual effects in interaction sequences and the structure of information-statistical models is discussed. In Appendix I computational procedures are specified; in Appendix II a Monte Carlo procedure for testing observed variability measures is presented.

Information-statistical analysis of factors determining ongoing behaviour and social interaction in Java monkeys (Macaca fascicularis)

Abstract Behavioural data from triads of Java monkeys ( Macaca fascicularis ) are used to compare several information-statistical models for the analysis of social interaction and communication. An analysis-of-variance (ANOVA) model relating the variability of the ongoing behaviour of a reference subject to both its own preceding behaviour and that of its partners fits the data best. The same data are also used to investigate certain formal aspects of communication by means of the ANOVA model; in particular, the role of observable orientation in behaviour as reflecting intention to communicate. Finally, behavioural data from observing a group of six Java monkeys are presented to show that the ANOVA model can provide parameters for describing group structure and dominance relations.