Duration and rate of reinforcement as determinants of concurrent responding

The duration and frequency of food presentation were varied in concurrent variable-interval variable-interval schedules of reinforcement. In the first experiment, in which pigeons were exposed to a succession of eight different schedules, neither relative duration nor relative frequency of reinforcement had as great an effect on response distribution as they have when they are manipulated separately. These results supported those previously reported by Todorov (1973) and Schneider (1973). In a second experiment, each of seven pigeons was exposed to only one concurrent schedule in which the frequency and/or duration of reinforcement differed on the two keys. Under these conditions, each pigeon's relative rate of response closely matched the relative total access to food that each schedule provided. This result suggests that previous failures to obtain matching may be due to factors such as an insufficient length of exposure to each schedule or to the pigeons' repeated exposure to different concurrent schedules.     

The dimensionality of the flanker compatibility effect: A psychophysiological analysis

The psychophysiological approach was used to evaluate the effects of feature similarity and intrinsic response mapping on the flanker compatibility effect. Symbol (e.g., < > < and < / <) and letter arrays (e.g., HCH and SCS) were used. Results showed that delays in stimulus evaluation and both peripheral and central response competition contributed to the compatibility effect, with the contribution of these processes depending on feature similarity and the intrinsic response mapping of the stimuli. For letter stimuli, the difference in the size of the compatibility effect for similar and dissimilar arrays could be accounted for in terms of stimulus evaluation. For symbol arrays, differences in size of the compatibility effect could be accounted for by response competition. Thus, symbol and letter arrays do not appear to be processed differently; what is different is the degree to which stimulus and response-related processes are affected by incompatibility.     

Relationship between cognitive style and emotional behavior.

In this research we examined the relationships among cognitive styles using the categorization of Bion and styles of modulation of emotional behavior (hostile content) explored with the Gottschalk, et al. method applied to the speech of 20 female and 10 male undergraduate students whose ages ranged from 20 to 35 years. Their verbalization was produced in a standard stimulus situation of 3 minutes duration. Analysis indicated a relationship between hostile attitude and cognitive styles. In particular, those who were relatively less hostile presented higher frequencies of processes classified by Bion as D2, which are characterized by an attitude of expectancy and waiting, with a tendency to defend internal psychological themas.