Mirror Neurons and the Evolution of Embodied Language

ABSTRACT— Mirror neurons are a class of neurons first discovered in the monkey premotor cortex that activate both when the monkey executes an action and when it observes the same action made by another individual. These neurons enable individuals to understand actions performed by others. Two subcategories of mirror neurons in monkeys activate when they listen to action sounds and when they observe communicative gestures made by others, respectively. The properties of mirror neurons could constitute a substrate from which more sophisticated forms of communication evolved; this would make sense, given the anatomical and functional homology between part of the monkey premotor cortex and Broca's area (the "speech" area of the brain) in humans. We hypothesize that several components of human language, including some aspects of phonology and syntax, could be embedded in the organizational properties of the motor system and that a deeper knowledge of this system could shed light on how language evolved.     

Extended Analysis of Empirical Citations with Skinner's Verbal Behavior: 1984-2004

The present paper comments on and extends the citation analysis of verbal operant publications based on Skinner''s Verbal Behavior (1957) by Dymond, O''Hora, Whelan, and O''Donovan (2006). Variations in population parameters were evaluated for only those studies that Dymond et al. categorized as empirical. Preliminary results indicate that the majority of empirical research in the area of verbal behavior has been conducted with the younger developmentally disabled population and has focused on verbal operants from the introductory chapters of Skinner''s book. It is clear that Verbal Behavior has influenced empirical research over the past 50 years. We believe, however, that there are many underdeveloped research areas originating from Verbal Behavior that have not yet been addressed. Suggestions for extended areas of research are provided.     

B. F. Skinner: The Writer and His Definition of Verbal Behavior

Skinner's definition of verbal behavior, with its brief and refined versions, has recently become a point of controversy among behavior analysts. Some of the arguments presented in this controversy might be based on a misreading of Skinner's (1957a) writings. An examination of Skinner's correspondence with editors of scientific journals shows his sophisticated mastery of English and his knowledge of contemporary approaches of linguistics, and might help to settle the meaning of the passages involved in the controversy. A more precise definition of verbal behavior, deduced from Skinner's distinction between verbal and nonverbal operants, is suggested, and a possible reason why Skinner did not define verbal behavior in the terms proposed by this alternative definition is discussed. The alternative definition is more compatible with a functional approach to behavior and highlights what is specific to verbal behavior by pointing to the conventions of the verbal community. Some possible consequences of adopting this alternative definition are described.     

Associative and categorical processes in children's memory: The role of automaticity in the development of organization in free recall

Free recall performance was assessed in children in Grades 3, 5, 7, and 9 (Experiment 1) and adults (Experiment 2) on a list of categorically related words constructed so that some items within a category were highly associated with one another and interitem associations were low among other items (e.g., dog, cat, cow, lion, tiger). Associative relations were used frequently in recall by subjects of all ages, with analyses of interitem latencies and correlations between recall and clustering indicating that organization in recall was based only on associative relations for the third and fifth graders but based on both associative and nonassociative categorical relations for older subjects. Examination of the placement of high associates in recall indicated that seventh- and ninth-grade children were more apt to use associative relations to begin category clusters than were younger children or adults. These children were hypothesized to use the relatively automatic activation of associative relations to instigate categorical organization and to represent a stage in development between nonstrategic younger children and strategic adults. The results were discussed in terms of the role that the automatic activation of semantic memory relations may play in the development of strategic memory organization.     

Self-focused attention and reactions to fear

Two studies were conducted to study the effect of self-focused attention on behavioral responses to fear. In Experiment 1, phobics and nonphobics were asked to approach and hold a snake either in the presence of a mirror or with no mirror. In Experiment 2, high and low private self-conscious subjects were asked to submit to a series of either mild or strong electric shock for humanitarian reasons. In each case, self-directed attention caused increased responsivity to the fearful affect and made subjects more likely to withdraw from the situation, regardless of the fact that a behavioral standard existed which called for an opposite response. The theoretical and behavioral implications of the findings were discussed.     

Anxiety and aggression of high and low assertive persons following conflict

This experiment examined changes in anxiety and differences in aggression for high and low assertive women when different degrees of conflict were encountered. As predicted, low assertive women were intially more uneasy or anxious than high assertive women when they were placed in a conflictual situation. When the level of actual conflict was low, the level of anxiety of low assertive women decreased. However, when the actual level of conflict was high the anxiety level of low assertive women remained unchanged. These results were taken as support for the fear of conflict hypothesis which predicted that the reduction in anxiety for low assertive persons is contingent upon whether or not the anticipated conflict is actually encountered. The results also indicated that high assertive women were not significantly more aggressive than low assertive women. This finding provided support for Galassi's position that assertiveness and aggression are distinct concepts.     

WHAT CAN PIAGET OFFER LONERGAN'S PHILOSOPHY OF BIOLOGY?

In Insight, Bernard Lonergan provides, albeit schematically, a unique philosophy of biology which he takes as having “profound differences” with the world view presented by Darwin. These turn on Lonergan's idea of “schemes of recurrence” and of organisms as “solutions to the problem of living in an environment.” His lapidary prose requires some deciphering. I present the broad lines of his philosophy of biology and argue that Jean Piaget's structuralism can shed light on Lonergan's intentions in virtue of his use of cybernetics and the isomorphism between biology and knowledge. In turn, Piaget draws on Waddington's restatement of epigenesis and I suggest that the result, “process structuralism,” is a viable alternative to the modern Darwinian synthesis.     

Category typicality effects in children's memory performance: Qualitative and quantitative differences in the processing of category information

Kindergarten, third, and sixth graders (6, 9, and 12 years of age, respectively) received a cue-at-input/cue-at-output recall task, using category typical and atypical items that were based on either (1) children's conceptions of item typicality, or (2) adults' conceptions of item typicality. At each grade level, recall was greater with the child-defined lists than with the adult-defined lists, and typical items were recalled to a greater extent than atypical items. Further analyses items were recalled to a greater extent than atypical items. Further analyses revealed that the recall of typical items varied as a function of children's typicality ratings of items, and that the “typicality effect” in the adult-norm condition was due primarily to the childrennot realizing that many of the atypical items were appropriate category exemplars. In contrast, typicality effects in the child-norm condition were attributed to qualitative differences in the judged “goodness of example” of the typical and atypical items. The results were discussed in terms of the appropriateness of typicality as a dimension of children's natural language concepts, the role of age differences in knowledge base in affecting performance on a cognitive task, and of the importance of using child-generated norms in studies of children's processing of category information.     

Effects of sucrose concentration and goal units on runway behavior in the rat

Experiment 1 investigated the between-S and within-S effects of sucrose concentration (32 and 6%) and number of goal units (equal volumes of sucrose presented in single or multiple goal cups). The goal-unit variable had no effect on behavior under any of several test conditions employed. Within-S effects of sucrose concentration were approximately equal to between-S effects; no contrast effects were found. When 64 and 6% sucrose solutions were used as reinforcers in Experiment 2, a simultaneous, but not a successive, negative contrast effect was found. Results were discussed in terms of possible functional differences between the successive and simultaneous contrast paradigms and between sucrose solutions and solid food as reinforcers.