The access of relevant information for solving problems

Two issues were investigated concerning the retrieval of recently acquired relevant information for solving riddle problems. First, although earlier research indicated that problem solvers often fail to retrieve relevant information unless they are explicitly informed of its relevance, Bowden (1985) suggested that uninformed subjects would benefit greatly from additional problem-solving time. In two experiments, we found that uninformed subjects solved more problems than did subjects who did not receive the information, but a simple model attributed this difference to these uninformed subjects "catching on" to the information's relevance after solving some problems. Second, the retrieval characteristics were examined by varying the proportion of problems for which clues were given. Informed subjects given clues for only half of the problems benefited (though perhaps not fully) from being informed, without incurring any cost from being misdirected on the unclued problems. The discussion focuses on some ways in which accessing relevant information may affect problem solving.     

The relation between gap discrimination and auditory stream segregation

Gap discrimination and stream segregation were examined using sequences of 2, 4, 8, or 16 tones. The frequency differences between tones ranged from 1/24 to 2 1/2 octaves. Judgments of stream segregation show large intersubject variability, whereas gap thresholds are comparatively stable. Gap thresholds and streaming judgments are both affected by the frequency separation between tones. However, only streaming judgments are affected by presentation rate. Gap-threshold functions show no discontinuities or plateaus with increasing frequency differences and faster presentation rates. These results suggest that stream segregation is not a primary factor limiting gap-discrimination performance in tonal sequences.     

Changes in Moods and Activation Levels During the Menstrual Cycle in Experimentally Naive Subjects

Two experiments providing additional validity data on the Profile of Mood States and the Thayer Activation-Deactivation Adjective Check List were per-formed. In the third and main experiment, seven normally menstruating women filled out both questionnaires at the same time every day for 90 days. They were not aware that they were participating in a study of menstruation. Analysis of the time series records of individual women revealed relatively few significant fluctuations in moods and activation levels. Analysis of the group data showed that Fatigue, Confusion, Deactivation/Sleep, and Depression/Dejection were significantly lower in the premenstrual phase than in the periovulatory phase of the cycle, while General Activation was higher. Anger/Hostility and Confusion were both lower in the menstrual phase than in the periovulatory phase. On a retrospective menstrual distress questionnaire, these same subjects say that they experience increases in anxiety, irritability, depression, and tension in the premenstrual phase of the cycle. The differences between individual and group data and the apparent discrepancy between daily self-reports and retrospective questionnaires are discussed.     

Developmental steps in the comparison and integration of information by grade-school children

The developmental sequence in 5- to 11-year-old children's attempts to combine two discrete stimuli was investigated by microanalysis of answers in an equivalence task. Eleven response types were identified and shown to form both a developmental and a hierarchical sequence of comparison and integration operations. An age-related progression in response abstractness was also found and a significant interrelation with response type was demonstrated. The evidence supported a construct of verbally mediated executive control over the interactions of short- and long-term memory.     

The rabbit as a subject in behavioral research

Domestic rabbits were exposed to a wide variety of variables employed in behavioral research. It was found that: (1) Although food could be used as a reinforcer, the long periods of severe deprivation required to reduce body weight made its use impractical. (2) Water was an efficient reinforcer in that it maintained high rates of behavior after 22 hr of deprivation. (3) Except that rates of responding were higher, fixed-ratio and variable-interval schedules of reinforcement produced patterns of behavior similar to those demonstrated by rats and pigeons. (4) Although the duration of the post-reinforcement pause was a function of the duration of the interval under fixed-interval schedules, scalloping, as defined as a gradually increasing rate of responding between reinforcement, was not evident. (5) When provided with the means to both turn on and turn off intracranial stimulation, the duration of the stimulation and the frequency with which it was turned on and off was a function of the intensity of the stimulation. (6) Electric shock could suppress behavior and maintain escape responding, but would maintain avoidance responding only in a few subjects.     

The comprehension of rate-incremented aural coding

Stimulus and psychological measures of a battery of 36 rate-manipulated versions of an extended message indicate that optimization of the efficiency of aural coding beyond that previously reported can be accomplished by the simultaneous application of a combination of natural and artificial distortions of the durational characteristics of speech. Peak efficiency of listening was successfully pushed to 400 wpm (words per minutes) primarily by means of a selective reduction of speech pause time. Regression estimates predicting the influence of pause time, total duration, and talker rate upon judgments of speech rate and comprehension are presented and implications for listening strategies and speech apperception drawn.This research was supported by grant HD02417 from the National Institute of Child Health and Human Development.     

Changes of pupil size and rehearsal strategies in a short-term memory task

Twelve subjects learned lists consisting of 3 groups of 4 items each drawn from vocabularies of digits, colour names or boys' names. There were two conditions of recall, total or partial, and two retention intervals, 3 and 7 sec. A view of the function of rehearsal suggests that rehearsal for total recall should be more intense than for partial recall, but only with a brief retention interval. Measurements of pupillary diameter confirm this prediction. Conditions under which pupillary measurements can serve to test theories of psychological processes are discussed.