A PRELIMINARY PROCEDURE FOR PREDICTING THE POSITIVE AND NEGATIVE EFFECTS OF REINFORCEMENT-BASED PROCEDURES

In the current investigation, a modification was made to the preference assessment described by Pace, Ivancic, Edwards, Iwata, and Page (1985) to predict the effects of stimuli when used in a differential-reinforcement-of-other-behavior (DRO) schedule for 2 clients with severe self-injurious behavior (SIB) and profound mental retardation. Based on the results of the preference assessment, three types of stimuli were identified: (a) high-preference stimuli associated with high rates of SIB (HP/HS), (b) high-preference stimuli associated with relatively lower rates of SIB (HP/LS), and (c) low-preference stimuli associated with low rates of SIB (LP/LS). Consistent with the results of the preference assessment, the DRO schedule with HP/HS stimuli resulted in increased SIB, and the DRO schedule with LP/LS stimuli resulted in no changes in SIB. HP/LS stimuli were demonstrated reinforcers but did not result in a change in SIB when used in a DRO schedule. Thus, the stimulus preference assessment may be useful clinically in some situations for predicting both the beneficial and the negative side effects of stimuli in DRO procedures.     

Effects of cocaine on briefly signaled versus completely signaled delays to reinforcement.

Key pecking by 4 pigeons was maintained by a multiple schedule consisting of two variable-interval 60-s schedules wherein each food presentation followed a nonresetting 27-s delay that was either briefly signaled at its outset or completely signaled. Brief-signal duration was adjusted so that response rates maintained by the briefly and completely signaled delays of reinforcement were similar. In general, acute administration of small to intermediate doses (0.3 to 3.0 mg/kg) of cocaine produced either small increases in response rates in both components or no change, and larger doses (5.6 to 13.0 mg/kg) decreased response rates. Chronic (i.e., daily) cocaine administration (10.0 mg/kg) resulted in tolerance to the rate-decreasing effects in both components. Cocaine's effects were generally similar whether delays were completely or briefly signaled. Discontinuation of cocaine administration and subsequent removal of the delay signals also had similar effects in both components of the multiple schedule. Taken together, these results are consistent with the view that the two types of delay signals were equally effective in maintaining responding during the variable-interval schedules.     

Changeover behavior and preference in concurrent schedules

Pigeons were trained on a multiple schedule of reinforcement in which separate concurrent schedules occurred in each of two components. Key pecking was reinforced with milo. During one component, a variable-interval 40-s schedule was concurrent with a variable-interval 20-s schedule; during the other component, a variable-interval 40-s schedule was concurrent with a variable-interval 80-s schedule. During probe tests, the stimuli correlated with the two variable-interval 40-s schedules were presented simultaneously to assess preference, measured by the relative response rates to the two stimuli. In Experiment 1, the concurrently available variable-interval 20-s schedule operated normally; that is, reinforcer availability was not signaled. Following this baseline training, relative response rate during the probes favored the variable-interval 40-s alternative that had been paired with the lower valued schedule (i.e., with the variable-interval 80-s schedule). In Experiment 2, a signal for reinforcer availability was added to the high-value alternative (i.e., to the variable-interval 20-s schedule), thus reducing the rate of key pecking maintained by that schedule but leaving the reinforcement rate unchanged. Following that baseline training, relative response rates during probes favored the variable-interval 40-s alternative that had been paired with the higher valued schedule. The reversal in the pattern of preference implies that the pattern of changeover behavior established during training, and not reinforcement rate, determined the preference patterns obtained on the probe tests.     

Electrodermal lability in anxiety disorders

Twenty-eight anxiety patients, aged below 50 years, were diagnosed according to DSM-III-R criteria (panic disorder with and without agoraphobia, generalised anxiety disorder, and anxiety disorder not otherwise specified). The patients were characterised by high levels of state and trait anxiety and neuroticism, compared with the controls. However, there were no differences between patients and controls in electrodermal habituation rate, non-specific activity, or skin resistance level. When the patients were divided into electrodermally labile and stable subjects, significant differences were found between patients and controls in both electrodermal activity and Eysenck's personality dimensions. The labile patients were more introverted and attained higher psychoticism scores than either the stable patients or controls. Duration of anxiety symptoms removed the difference found in extroversion, but not in any other variable. The results are discussed in relation to the utility of electrodermal measurements in validation of diagnostic entities. It is concluded, that from the psychophysiological point of view, anxiety disorders may be examined within a dimensional framework.     

Decompositions and biplots in three-way correspondence analysis

In this paper correspondence analysis for three-way contingency tables is presented using three-way generalisations of the singular value decomposition. It is shown that in combination with Lancaster's (1951) additive decomposition of interactions in three-way tables, a detailed analysis is possible of the deviations from independence. Finally, biplots are shown to produce powerful graphical representations of the results from three-way correspondence analyses. An example from child development is used to illustrate the theoretical developments.     

Contrary-to-duty obligations

We investigate under what conditions contrary-to-duty (CTD) structures lacking temporal and action elements can be given a coherent reading. We argue, contrary to some recent proposals, that CTD is not an instance of defeasible reasoning, and that methods of nonmonotonic logics are inadequate since they are unable to distinguish between defeasibility and violation of primary obligations. We propose a semantic framework based on the idea that primary and CTD obligations are obligations of different kinds: a CTD obligation pertains to, or pre-supposes, a certain context in which a primary obligation is already violated. This framework is presented initially as an extension of Standard Deontic Logic (SDL), a normal modal logic of type KD, and is illustrated by application to a series of examples. The concluding section is concerned with some resemblances between CTD and defeasible reasoning. We show first that the SDL-based framework contains a flaw and must be adjusted. A discussion of possible adjustments, including an alternative treatment in terms of a preference-based semantics, reveals difficulties that are reminiscent of problems in defeasible reasoning and intensional accounts of defeasible conditionals.     

General education,cultural diversity,and identity

The issue of this paper is cultural plurality as a problem for public, general education and for (personal) identity. In order to examine this question, one needs to be clear about the meaning of the concepts of general education, on the one hand, and cultural diversity on the other. In the first section, we will fix the meaning of these concepts. A conceptual distinction between cultural diversity and cultural pluralism will be introduced. In the second section, it will be argued that open pluralism can only be maintained if there is a basic common culture apart from the cultural diversity that pluralism affirms. Therefore, there is yet an indispensable role for general education in an open, pluralistic society. In the third section we will look at two metaphors that give an opposite significance to the relation between identity and diversity: the conversational metaphor and the food metaphor mishmash. The final section expands on the conversational metaphor by way of an exposition of Ricoeur's hermeneutics of the self. It supplies us with a promising concept of identity that is not in complete opposition to diversity.     

Is community necessary? Quasi-philosophical ruminations

In responding to and examining Mary Anne Raywid's (1989) adoption of community building as an aim for schools, I survey a number of types of communities, including recreational, intentional and language communities. In considering all these communities, I try to show both the power of communities in our personal lives and some idea of why we might be of two minds about promoting community as an ideal in the modern world and in schools in particular.     

Ecology, Community, and AIDS Prevention

I explore the role that may be played by an ecological view of AIDS prevention and AIDS-related social concerns. The study of AIDS risk behavior and interventions designed to prevent AIDS have challenged Health Psychology's typically individualistic perspective. Issues of empowerment, psychological sense of community, interpersonal ties, resources, and culture are central to an understanding of risky sexual behavior and helping people to guard themselves from the threat of AIDS. However, despite Community Psychology's historical expertise in these areas, the field has only recently become involved in AIDS prevention efforts. I outline how resource-based, ecological theories may prove more helpful in addressing the AIDS pandemic than the individual, cognitive theories that have typically been adopted. Sexual behavior and associated risk are tied not simply to people's personal behavior and thoughts but to the likelihood of disease exposure in their ethnic group, the power and choices associated with power in that group, and the alternative means available of meeting their overall sexual, romantic, economic, and social goals. As such, AIDS research and intervention must simultaneously address the individual, social, and cultural spheres if insights that can translate to meaningful change can be expected to occur.