Ventral scent marking in Meriones unguiculatus may contribute to thermoregulation

Three experiments were conducted with adult male Meriones unguiculatus in an attempt to demonstrate that ventral scent marking can act to transfer body heat to the object marked. Experiment 1 showed that surgical removal of the ventral gland pad reduced the amount of heat transferred by 50%, even though intact and glandless animals did not differ in the average frequency of scent marking. Experiment 2 demonstrated that the difference in heat transfer due to the presence or absence of the scent pad was not due to differential pressure applied to the substrate during marking. Experiment 3 showed that the pattern of ventral hair spread that occurs as an animal moves over an object is different between intact and glandless animals but that this difference does not account for the difference in heat transfer. It is suggested that heat transfer to the environment with ventral scent marking may increase thermoregulatory competence and also may function to volatilize sebum used in chemocommunication.     

Color discrimination on Mangaia

Bornstein’s hypothesis that there is a loss of color discrimination in tropical areas was not supported in earlier research in the Cook Islands. Using a more sensitive color vision test (the Farnsworth-Munsell 100-Hue Test), a loss of color discrimination in the red-purple and blue-green regions of the spectrum was found. The lack of sex differences in this color discrimination loss supports a physiological rather than a genetic explanation of the observed decrement.     

Doctoral training in behavior analysis: Training generalized problem-solving skills

This essay provides guidelines for designing a doctoral program in behavior analysis. First, we propose a general accomplishment for all behavior analytic doctoral students: that they be able to solve problems concerning individual behavior within a range of environments. Second, in order to achieve this goal, we propose that students be trained in conceptual and experimental analysis of behavior, the application of behavioral principles and the administration of behavioral programs. This training should include class work, but it should emphasize the immersion of students in a variety of environments in which they are required to use behavior analytic strategies. Third, we provide an example of a hypothetical graduate program that involves the proposed training. Finally, an evaluation plan is suggested for determining whether a training program is in fact producing students who are generalized problem-solvers. At each step, we justify our point of view from a perspective that combines principles from behavior analysis and educational systems design.     

Understanding and solving arithmetic word problems: A computer simulation

In this paper, I describe a computer program, WORDPRO, which simulates the psychological processes involved when third-grade children understand and solve simple arithmetic word problems. Both the implementation of the program and its performance on a set of sample problems are presented. WORDPRO is a useful research tool in that it demonstrates the sufficiency of the theory upon which it is based, assists in communicating that theory to other researchers, and provides a sources of empirical predictions for experimental tests of the theory.     

Contextual stimulus control of conditional vasomotor and electrodermal reactions to angry and friendly faces

An experiment with 42 human Ss used the transswitching procedure to examine tonic stimulus control of phasic and tonic conditioned vasomotor heart rate, and electrodermal reactions. The conditional stimulus (CSs) were photos of angry and friendly human faces, and the unconditional stimulus (US) was a human scream. In one tonic context (blue light), the CSs were paired with the US, in the other context (yellow light), the CSs were presented unpaired. Following acquisition, an extinction series was run with the US omitted during both tonic contexts. Phasic vasomotor and skin conductance reactions differed in the positive and negative tonic segments (stronger in positive). The skin conductance responses also differed during extinction, but the vasomotor responses did not. Tonic differences (following onset of the tonic stimuli) in unelicited skin conductance response frequency, finger pulse volume, and heart rate were also found, although these developed more slowly than the phasic differences. The finger pulse volume tonic difference was greater in extinction than the skin conductance response frequency. There was no effect of the angry-friendly facial expressions, either directly or in interaction with the transswitching effects. The results were interpreted to mean that the transswitching phenomenon is not limited to one another autonomic effector, but is more generalized across the ANS (sympathetic branch). The absence of influence of the facial expressions indicates the relative weakness of the “preparedness” hypothesis in comparison with more influential contextual factors.     

Achromatic color categories

Sternheim and Boynton’s (1966) continuous judgmental color-naming technique was used to assess the elemental nature of achromatic colors. Results from three subjects indicate that the names “black” and “white” are necessary and sufficient to describe achromatic test lights associated with the name “gray.” On the basis of the criteria that establishes a color as elemental, black and white were confirmed as elemental, whereas gray was not. These findings support the assumption of various opponent processing models that there are only two elemental achromatic sensations. In addition, the results support Hering’s (1920) view that black and white differ from the paired-chromatic opponent colors in that they are not mutually exclusive.