Effects of alternative reinforcement on human behavior: the source does matter

Competing theories regarding the effects of delivering periodic response-independent reinforcement (more accurately, response-independent points exchanged for money) on a baseline rate of behavior were evaluated in human subjects. Contiguity theory holds that these events decrease target responding because incompatible behavior is adventitiously strengthened when the point deliveries follow target behavior closely in time. Matching theory holds that response-independent points, like any other alternative reinforcer, should reduce target responding. On this view, temporal contiguity between target responding and response-independent point delivery is unimportant. In our experiment, four different responses (moving a joystick in four different directions) were reinforced with points exchangeable for money according to four independent variable-interval schedules. Different schedules of point delivery were then superimposed on these baselines. When all superimposed point deliveries occurred immediately after one of the four responses (the target response), time allocated to target responding increased. When the superimposed point deliveries could be delivered at any time, time allocated to target responding declined and other behavior increased. When superimposed points could never immediately follow target responses, time allocated to target responding decreased further and other behavior or pausing predominated. The findings underscore the contribution of temporal contiguity in the effects of response-independent deliveries of food, money, points, etc.     

Fixed-time schedule effects as a function of baseline reinforcement rate

Using an arbitrary response, we evaluated fixed-time (FT) schedules that were either similar or dissimilar to a baseline (response-dependent) reinforcement schedule and extinction. Results suggested that both FT schedules and extinction resulted in decreased responding. However, FT schedules were more effective in reducing response rates if the FT reinforcer rate was dissimilar to baseline reinforcer rates. Possible reasons for this difference were evaluated with data analysis methods designed to identify adventitious response-reinforcer relations.     

Beyond the Obvious: Chronic Vividness of Imagery and the Use of Information in Decision Making

The authors investigate two competing hypotheses about how chronic vividness of imagery interacts with the vividness and salience of information in decision making. Results from four studies, covering a variety of decision domains, indicate that chronic imagery vividness rarely amplifies the effects of vivid and salient information. Imagery vividness may, in fact, attenuate the effects of vivid and salient information. This is because, relative to nonvivid imagers, vivid imagers rely less on information that appears obvious and rely more on information that seems less obvious. This tendency is so robust that vividness of imagery may amplify the effects of vivid information only when this information is the only information available in the decision field. The findings seem to reflect vivid imagers' tendency to totally immerse themselves in a decision problem and scrutinize the available information creatively.     

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.     

Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

The Humanizing Brain: An Introduction

The rediscovery of the sacred needs to take into account the neural underpinnings of faith and meaning and also draw on the insights of the emerging discipline of complexity studies, which explore a tendency toward adaptive self-organization that seemingly is inherent in the universe. Both neuroscience and complexity studies contribute to our understanding of the brain's activity as it transforms raw stimuli into recognizable patterns, and thus "humanizes" all our perceptions and understandings. The brain is our physical anchor in the natural environment— and its human capacities orbit us into the emerging world of culture (including religion), which provides a template for the brain's function of making sense of an ambiguous reality. The humanizing brain holds together scientific causality and religious meaning, working both bottom-up (linking the physical and the experiential) and top-down (beginning with the whole of things, or God). These processes we know as "mind" (experienced as intentionality, subjective consciousness, empathy, imagination, memory, adaptability). We maintain that such processes are not only subjective but built into "the way things really are." Thus, they carry the most privileged information about the nature of reality to which we human beings have access. For not only are we humans observers and logicians, but we are embedded in the larger reality; and as we strive to make sense of it all, we become both Homo sapiens and Homo religiosus .     

Embodied Knowledge and Making Sense of Prenatal Diagnosis

Open-ended, qualitative interviews with women to whom amniocentesis was offered were analyzed to understand how women made sense of these tests. We found that women, whether tested or not, negotiated with biomedical information. They transformed it through identifiable processes, then wove it with their own instincts and beliefs and with their personal experiences, thereby creating embodied knowledge on which their decisions were based. Women who were and were not tested may have differed from each other when categorized on the basis of a final, binary choice, but they were more alike than unalike in reaching this point. The apparent importance of embodied knowledge suggests the critical role of the listening activities of the genetic counselor and of awareness of the validity and importance of women's complementary ways of knowing and doing in understanding the uses and meanings of prenatal genetic testing.     

Quantitative Anatomy: Power Beyond the Images

Positron emission tomography (PET) is a frontiermedical technology that, in contrast to the othercomputer-assisted technologies providing anatomicalpictures, produces functional images. I argue that PETalso opens up an avenue for shifting from images (asa tool for representation of biomedical data) back toanalysis of measurements (as a tool for quantificationof physiology). Admittedly, quantification of functionrequires structural constraints. I coined the emerginginterpretational framework quantitative anatomyin an attempt to conceptualize the PET merger betweenmeasuring and imaging, the two competing meansmedicine uses to examine the human body. Anatomyjustifies interpretations that fit the existingknowledge of a larger clinical audience, whilestatistical data possess an unexplored potential tointroduce mathematical rigor in the evaluation offunction, but are still a black box for the majorityof clinicians. This epistemological change is beingcarried out by PET users in action as well as indiscourse.     

The influence of adults' actions on children's inferences about word meanings

This article first establishes the effect of adults' actions on children's inferences about the shape and material of solid objects, based on data from Japanese 2-, 4-, and 6-year-olds. Japanese 2-year-olds are already sensitive to adults' actions in making inferences, and children become more adept at this as they become older. The invariance of the phenomenon of the effect of actions is then discussed in terms of three of its aspects: across age groups, across languages (the universality of the effect), and across tasks in lexical development. It is suggested that while specific linguistic characteristics (e.g., the means of individuation of entities), and complexity of object shape probably influence the effect of actions, action effects may have a potentially invariant/universal aspect.     

Dissociation and the self in the magical pre-Oedipal field

This paper explores the clinical relevance of Jung's idea of the Self in pre-Oedipal and pre-individuation psychology. Incorporating data from neurobiology and recent theories of memory and narrative reconstruction, a post-modern conception of the Self is proposed akin to what Jung called a 'dream of totality'. Such a conception of the Self is distinguished from a reified structure or a deified imago, and is considered to be that aspect of psychological functioning consonant with emerging meanings, and the birth of new psychological ground. Links are made back to Flournoy, William James, and depth psychology's early interest in teleology, the occult, and the creative capacities of the psyche. Updating this mystery tradition, clinical material illustrates how narratives of the Self are present in such pre-Oedipal dynamics as dissociation and projective identification. These dynamics are understood not only as primitive defences but as reconstitutive symbolic metaphors and mythopoetic expressions of an emergent rather than a superordinate Self.