A bite manipulandum for the development of operant behavior in predacious fishes

An inexpensive bite manipulandum is described for use in operant conditioning studies with predacious fishes such as the largemouth bass. Compression of a rubber nipple by a fish bite is transduced by a mounted phonograph speaker. The use of the fish’s natural foods as rein-forcers in conjunction with this device makes it possible to obtain schedule-of-reinforcement data not previously obtainable with this species. Sample interval and ratio data are provided.     

The relationship between memory for order and other cognitive tasks

Measures of memory for order were correlated with measures requiring mental manipulation, achievement, and aptitude using college and fifth grade students. Memory for order was not significantly related to measures of mental manipulation nor achievement measures for college students. For fifth graders memory for order was significantly related to mental manipulation, intelligence, and achievement measures. It is suggested that the nature and capacity of short-term memory changes with age.     

A computer-controlled vapor-dilution olfactometer

A computer-controlled olfactometer with several innovations leading to closer control over the stimulus parameters and minimization of nonolfactory cues is presented. A microcomputer is used to control the stimulus duration and interstimulus interval. Electronic mass flow con-trollers are employed to maintain close control over the flow in the pure air line and the stimulus-bearing line. Both humidity and temperature are closely regulated. Using a nasal catheter, this stimulus delivery system coupled with velopharyngeal closure and oral breathing permits accurate specification of the quantity of stimulus material actually entering a subject’s nares. The design is such that the computer programming, patch panel interface, and threaded tubing allow versatility in the type of olfactometric study that can be conducted. This system is amenable for threshold, electrophysiological, and sensory adaptation studies of olfaction.     

Brain mechanisms in fatal cardiac arrhythmia

Intravenous injection of histamine to rabbits was used as a prototype in an investigation of the mechanism of sudden death due to anaphylaxis and other causes. The “dive” reflex, bradycardia due to activation of the ophthalmic branch of the fifth cranial nerve, was induced in thirty-seven of the animals while they inhaled a very small amount of cigarette smoke. Associated with the resulting bradycadia were lowered blood pH and increased serum content of lactic acid and potassium and increased peripheral arterial constriction with elevation of diastolic blood pressure. Intravenous injection of 1 ml of histamine in the presence of the dive reflex induced potentially fatal ventricular arrhythmia, but no cardiac disturbance when administered while the dive reflex was inactive, thereby strongly suggesting that sudden death in anaphylaxis may involve an overzealous response to a normally protective neural reflex.     

The College Dropout: Qualities of His Environment

Results of research on college dropouts paint both a negative and a confusing picture of this group. The argument presented in this paper is that consideration of the college student's environment can help to resolve some of the apparent contradictions among the various characteristics of the college dropout. Several environmental dimensions hypothesized to be relevant to the learning process are discussed. Against the background provided by these dimensions, two approaches to the student's interaction with his environment are described. One of these approaches is based on knowledge about the learning process, the other on a developmental conceptualization of the college experience.     

Influence of infant and child facial cues of low body weight on adults' ratings of adoption preference,cuteness, and health

Infant and child facial cues have been shown to influence decisions and perceptions associated with parental care in adults. Low body weight reflects health problems in infants and children; therefore, facial cues associated with low body weight may influence adult cognitive processes associated with parental care and investment. Facial images of infants and children were digitally manipulated to simulate cues of low body weight and presented to adults using a hypothetical adoption paradigm. Participants' ratings of adoption preference, cuteness, and health were significantly lower for the digitally manipulated low body weight facial images than their unaltered counterparts. These findings support the hypothesis that facial cues of poor health negatively influence adults' responses to infants and children.     

Gone but Not Forgotten: Council Leaders, 1934–1952

The authors summarize the contributions of several leaders of the American Council of Guidance and Personnel Associations, explaining that the counseling profession owes its origin to a coalition of professional organization leaders who were committed to guidance and personnel services. In explaining these leaders' contributions, the authors provide readers with an opportunity to connect a part of the American Counseling Association's past with the present.     

Time and cognitive load in working memory

According to the time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004), the cognitive load a given task involves is a function of the proportion of time during which it captures attention, thus impeding other attention-demanding processes. Accordingly, the present study demonstrates that the disruptive effect on concurrent maintenance of memory retrievals and response selections increases with their duration. Moreover, the effect on recall performance of concurrent activities does not go beyond their duration insofar as the processes are attention demanding. Finally, these effects are not modality specific, as spatial processing was found to disrupt verbal maintenance. These results suggest a sequential and time-based function of working memory in which processing and storage rely on a single and general purpose attentional resource needed to run executive processes devoted to constructing, maintaining, and modifying ephemeral representations.