Global supervenience and belief

Global supervenience of beliefs about physical states of affairs on such states has strongly counter-intuitive consequences about what beliefs we can nomologically hold. This is an argument against a global supervenience of all mental properties on physical ones, and, since that is implied by strong supervenience, also against that as the preferred materialist thesis.     

Neonatal finger and arm movements as determined by a social and an object context

What kind of hand and finger movements are newborn infants preoccupied with, and how are these movements organized and controlled? These questions were studied in two experiments under three conditions: a social condition, in which the mother (in expt 1) or the experimenter (in expt 2) sat face to face with the infant; an object condition, in which a ball moving slowly and irregularly was presented to the infant; and a baseline condition (in expt 1) without ball or mother present. The size of the ball and the distance to it was chosen so that it approximately corresponded to the visual angle of the head of the model. Twenty-six neonates participated in the study ranging from 2 to 6 days of age at the time of observation. All infants were in an alert, optimal awake state during the experiments. The infants' finger movements were scored from video recordings. The result revealed a large variety of relatively independent finger movements. It was found that finger movements differed both in quantity and quality between the three conditions. There were many more finger movements in the social condition than in the object and baseline conditions. In addition, there were relatively more transitional finger movements and flexions of the hand in the social condition, and relatively more thumb-index finger activity and extensions of the hand in the object condition. Finally, the arms were more often forward extended in the object condition than in the social condition. The results support the notion that neonates show different modes of functioning towards people and objects.     

Changes of Cingulothalamic Topographic Excitation Patterns and Avoidance Response Incubation over Time Following Initial Discriminative Conditioning in Rabbits

Neurons in particular layers of cingulate cortex and in limbic thalamic nuclei exhibit peak firing rates in response to a positive conditional stimulus (CS+) in particular stages of discriminative learning. A given area is maximally activated by the CS+ in the initial, an intermediate, or a late stage of behavioral acquisition, and activation in all of the areas diminishes as training continues after the peak of activation occurs. Thus, the topographic distribution of activation in these areas depends on the stage of behavioral acquisition. The present study determined whether the acquisition-related changes of the topographic distributions of peak firing rates in CS-elicited activity are driven exclusively by the repetition of conditioning trials (i.e., practice) or may occur as well with the passage of time, similar to putative processes of memory consolidation. Multiunit activity was recorded in cingulate cortex and in the anterior dorsal (AD), anterior ventral (AV), and medial dorsal (MD) thalamic nuclei as rabbits learned to step in response to a warning tone (CS+) to prevent a scheduled foot-shock, and to ignore a different tone (CS-) not predictive of foot-shock. The rabbits received two training sessions, S1 and S2. S2 followed S1 immediately in one group of rabbits and after 48 h in a different group. Significant neuronal discharge increments occurred from S1 to S2 in the 48-h group but not in the 0-h group, for the areas (posterior cingulate cortex, AV thalamic nucleus) that previously showed only late-stage activation. Significant discharge increments occurred from S1 to S2 in the 0-h group but not in the 48-h group in areas (anterior cingulate cortex, the AD, and MD thalamic nuclei) that previously exhibited early stage activation. These results indicate that the trial-driven topographic distribution changes also occur with the passage of time after limited initial training. It is suggested that the trial-driven and time-related changes may have a common functional relevance concerning memory consolidation.     

Hand Skill Asymmetry in Professional Musicians

Hand skill asymmetry on two handedness tasks was examined in consistent right-handed musicians and nonmusicians as well as mixed-handed and consistent left-handed nonmusicians. Musicians, although demonstrating right-hand superiority, revealed a lesser degree of hand skill asymmetry than consistent right-handed nonmusicians. Increased left-hand skill in musicians accounted for their reduced asymmetry. Musicians predominantly playing keyboard instruments demonstrated superior tapping performance than musicians playing predominantly string instruments, although they did not differ with respect to hand skill asymmetry. Since the diminished tapping asymmetry in musicians was related to early commencement but not duration of musical training, results are interpreted as an adaptation process due to performance requirements interacting with cerebral maturation during childhood.     

Infants' sensitivity to differential luminance as information about depth

To what degree are young infants able to perceive differential shadowing and to what degree are they able to utilize this stimulus parameter as information about depth? Two habituation experiments were performed. In Experiment 1, a group of 5-month-old infants were habituated to a low frequency, vertical, and approximately sinusoidal luminance grating superimposed on a flat colored surface. This display induced stable 3-D perception in adult subjects. After habituation, the infants viewed two test displays at alternating trials. One was made up of real half cylinders matching the light distribution of the habituation display and the other was made up of a square wave grating of the same spatial frequency as in the habituation one. Adults perceived the latter display as flat. Results showed that both test displays were treated as new ones by the infants habituated to the sinusoidal grating. Experiment 2 was identical to Experiment 1, except that the subjects were 3 1/2-month-old. These infants treated the half cylinders as familiar and the square wave grating as new. The results indicate that infants at both age levels (3 1/2 and 5 months of age) were sensitive to the difference between sharp and gradual change in luminance which is a prerequisite for perceiving form from luminance. However, neither age group seemed to utilize gradual change in luminance as information about space.     

Independence and interdependence of group judgments: Xenophobia and minority influence

A first experiment examined the effects of two methods of dividing resources between Swiss nationals and foreign residents in a study involving 118 subjects. Subjects gave judgments involving either interdependent allocation (resources allocated to the outgroup cannot be allocated to the ingroup) or independent allocation. The results indicated that the socio-cognitive functioning preferred by subjects varies as a function of their view of outsiders. Interdependence of judgments was more characteristic of the most xenophobic subjects, whereas the least xenophobic were more likely to reason in terms of independence. On the other hand, intermediate subjects (those who were clearly neither for nor against outsiders) were sensitive to these modalities of judgment: interdependence engendered an ingroup favoritism, while independence counteracted this bias. A second experiment further analysed the influence of a more or less imperative minority argument on the attitudes of 109 more xenophobic subjects. Independent as compared to interdependent judgment facilitated a latent influence by the source, especially when the source employed a more imperative rhetoric to urge a more favourable attitude to foreigners.     

Behavioural conversion in a compliance paradigm: A replication and a refinement

While a compliance strategy induced almost all subjects to agree to forego first a lunch and then a dinner and the following breakfast, simply observing an accomplice break his commitment to forego lunch was enough to produce a significant reduction in subjects' commitment to forego two meals, even though the effect was not immediate. This pattern of influence, similar to a ‘behavioural conversion’, appeared if the accomplice had first agreed to the initial request and only later refused to continue, but not if he refused to make the commitment at the outset.