On the Correlation between Synchronized Oscillatory Activities and Consciousness

Recent experiments have shown that the amplitudes of cortical gamma band oscillatory activities that occur during anesthesia are often greater than amplitudes of similar activities that occur without anesthesia. This result is apparently at odds with the hypothesis that synchronized oscillatory activities constitute the neural correlate of consciousness. We argue that while synchronization and oscillatory patterning are necessary conditions for consciousness, they are not sufficient. Based on the results of a binocular rivalry study of Fries et al. (1997), we propose that the degrees of oscillatory strength and synchronization of neuronal activities determine the degree of awareness those activities produce. On the other hand, the overal firing rates of neurons in cortical sensory areas are not correlated with the degree of awareness the activities of those neurons produce. The results of the experiment of Fries et al. (1997) appear to conflict with the results of another binocular rivalry experiment, in which monkeys were trained to pull a lever in order to report which stimulus object was being perceived (Leopold & Logothetis, 1996). In the latter experiment, it was demonstrated that the firing rates of neurons in striate cortex did not change during perceptual alterations, while 90% of neurons in inferior and superior temporal cortices changed their firing rate when the perceived image changed. This result led to the conclusion that activities in temporal cortex are correlated with visual awareness, but those in striate cortex are not. We argue that activities in temporal cortex contribute little, if anything, to perceptual awareness, and that their primary function is computational. Thus the correlation between the firing rates of neurons in these areas and the responses of the monkeys is due to the recognition of a particular stimulus object, which in turn is due to the computations made there.     

Influence of two types of information trials on the formation of a discrimination-reversal learning set in Japanese monkeys

Abstract: Three groups of male adult Japanese monkeys were trained in 30 discrimination-reversal learning-set (LS) problems using the Wisconsin General Test Apparatus. A control group ( N = 3) was trained in the standard procedure: acquisition of up to 12 consecutive correct responses, reversal to the same criterion, and then shift to a new problem. To the other two groups, three information trials signaling the stimulus value in reversal were given after they reached the criterion in acquisition. Subjects in the positive-stimulus information (PSI) group ( N = 4) were exposed only to the reversal positive stimulus, and a response to it was rewarded. Subjects in the negative-stimulus information (NSI) group ( N = 4) were exposed only to the reversal negative stimulus, and any response to it was not rewarded. Information trials reduced reversal errors and NSI trials were more effective than PSI trials in error reduction ( p < .05). Information trials also aided in acquisition: the NSI and PSI groups learned the acquisition phase of the problems with significantly fewer errors than control group ( p < .01) in the last stage of training. The implications of these results are discussed in relation to strategy learning and attention learning in LS formation.     

Perceptual unit formation in simple motion patterns

The present study investigated the proximal constraints that determine perceptual unit formation under minimal stimulus conditions. Projections of three moving dots, which could form two possible two-dot configurations, were presented to naive observers. In a forced-choice situation, their task was to report which two-dot configuration was perceived as a distinct perceptual unit. The results showed that common motions (arbitrary translations and rigid rotations in the frontoparallel plane) have stronger grouping power as compared to different relative motions (expansions/contractions, or simultaneous expansions/contractions and deformations in the frontoparallel plane). It was found that proximal changes of distances between elements in two-dot structures reduce grouping power. Changes of proximal directions, however, did not affect unit formation in two-dot structures at all. The effect of vector algebraic combinations on grouping power in three-dot strutures was also investigated. Evidently, visual vector analysis splits up motion combinations into their constituents, and in come cases this contributes to additive effects.     

MEASURING REFLECTIVE SUPERVISION WITHIN HOME VISITING: CHANGES IN SUPERVISORS’ SELF‐PERCEPTION OVER TIME

Despite widespread belief in the early childhood field of the benefits of reflective supervision, there has been limited empirical evidence to support the effectiveness of reflective supervision for home visitors and the children and families they serve. The present study examined the psychometric properties of four adapted self‐report measures assessing supervisors’ reflective supervision capacities; the study also investigated whether these measures captured change in reflective capacity over time as supervisors participated in professional development activities focused on reflective supervision. Results from 33 participants (home visiting supervisors and program managers) suggested that three of the four measures demonstrated acceptable internal consistency, and these three measures were correlated with each other. Two of these measures also captured significant change over time. Finally, there was some evidence that those with less education demonstrated more substantial improvement in their reflective supervision capacities than did those with an advanced degree. Findings provide initial evidence for reliable, efficient, and cost‐effective supervisor self‐report measures that could be used in research and program evaluation to assess change in supervisor reflective capacity over time.     

Learning from exemplars: emulation,character formation and the complexities of ordinary life

In the field of character education role-modelling is advocated as an important pedagogical strategy. It is supposed that students learn from ‘significant others’ who exemplify important virtues and values. However, in these strategies it is not clear what and how students precisely can and should learn from exemplars and how the following of exemplars relates to the educational aim of ‘becoming a self.’ In this article, it is argued that modelling is only a relevant pedagogical strategy if moral exemplars are somehow related to life in its full extent, including its moral complexities and ambiguities. Understanding moral exemplarity demands not only the reappropriation of an Aristotelian conception of emulation but also an understanding of the typical modern relocation of moral exemplarity in the fullness of life, importantly originating from what Charles Taylor calls the Protestant ‘affirmation of ordinary life.’ In addition, a distinction is introduced between ‘role exemplarity’ and ‘existential exemplarity.’ Based on this distinction it is argued that emulation should not be limited to learning from role models, but should also include something that runs deeper, to the depth of our own subjectivity or self.     

Past tense formation and comprehension of passive sentences in Parkinson's disease: evidence from Greek

The present study investigates the production of regular and irregular verbs in the past tense and the comprehension of passive sentences by Greek-speaking PD patients, and compares their behavior to that of normal speakers. Although the two groups manifest large scale differences at all the above constructions, the behavior of PDs is not different at regular vs. irregular past tense formation neither did we obtain strong evidence that they do not comprehend passives, most importantly, they certainly do not perform at chance. On the basis of the above, we conclude that there are no indications for a clearly linguistic deficit of the PD group, hence, their difference with the control group should be attributed to other factors, such as the computational demands of the tasks.     

The development of interpretations for novel noun-noun conceptual combinations during the early school years

This research investigates issues surrounding early school children's use of the similarity between head and modifier terms in deriving interpretations for novel noun-noun conceptual combinations. In these experiments, 6- and 9-year-olds and adults were asked to formulate interpretations of similar and dissimilar conceptual combinations. Both children and adults were sensitive to the similarity aspect of conceptual combinations, although the children had some difficulty with the property interpretations that high-similarity combinations require. Next, we examined 40 popular children's books for the presence of noun-noun conceptual combinations. Adult participants provided interpretations for these combinations and rated the similarity of the head and modifier nouns. Results indicated that there were few high-similarity combinations and few combinations requiring property interpretations, suggesting that children have limited exposure to highly similar combinations and property interpretations. Further analysis of children's interpretations indicates that they may have difficulty in selecting and integrating properties of the modifier onto the head, a process required by property interpretations.     

Developing knowledge of objects' motion properties in infancy

Three experiments with a novel variation of the inductive generalization procedure examined 18- and 22-month-olds' knowledge of objects' motion properties. Infants observed simple air and land movements modeled with an appropriate category member (e.g. dog) or an ambiguous block and were allowed to imitate with one or more of four exemplars. The experiments show that 18-month-olds' knowledge of land motions is grounded in causally relevant object parts, whereas 22-month-olds relate such motions more broadly to appropriate category members. Infants' basis for generalizing air motions suggested that at 22 months they have little knowledge about objects from that domain. The results are discussed in relation to the early development of the animate-inanimate distinction and the nature of the inductive generalization task.     

Book Reviews

Dalton, Dennis, Mahatma Gandhi: Nonviolent Power in Action
Goodman, David G. and Miyazawa, Masanori, Jews in the Japanese Mind: The History and Uses of a Cultural Stereotype
Rejai, Mostafa and Phillips, Kay, World Military Leaders: A Collective and Comparative Analysis     

Asymmetrical responding to male versus female other-race categories in 9- to 12-month-old infants

Faces can be categorized along various dimensions including gender or race, an ability developing in infancy. Infant categorization studies have focused on facial attributes in isolation, but the interaction between these attributes remains poorly understood. Experiment 1 examined gender categorization of other-race faces in 9- and 12-month-old White infants. Nine- and 12-month-olds were familiarized with Asian male or female faces, and tested with a novel exemplar from the familiarized category paired with a novel exemplar from a novel category. Both age groups showed novel category preferences for novel Asian female faces after familiarization with Asian male faces, but showed no novel category preference for novel Asian male faces after familiarization with Asian female faces. This categorization asymmetry was not due to a spontaneous preference hindering novel category reaction (Experiment 2), and both age groups displayed difficulty discriminating among male, but not female, other-race faces (Experiment 3). These results indicate that category formation for male other-race faces is mediated by categorical perception. Overall, the findings suggest that even by 12 months of age, infants are not fully able to form gender category representations of other-race faces, responding categorically to male, but not female, other-race faces.