Unit price as a useful metric in analyzing effects of reinforcer magnitude.

In this paper, we applied the behavioral-economic concept of unit price to the study of reinforcer magnitude in an attempt to provide a consistent account of the effects of reinforcer magnitude on behavior. Recent research in the experimental analysis of behavior and in behavioral pharmacology suggests that reinforcer magnitude interacts with the schedule of reinforcement to determine response rate and total consumption. The utility of the unit-price concept thus stems from its ability to quantify this interaction as a cost-benefit ratio (i.e., unit price = characteristics of the schedule of reinforcement divided by magnitude of reinforcement). Research employing the unit-price concept has shown that as unit price increases, a positively decelerating function exists for consumption (i.e., a function with an increasingly negative slope, when plotted on log coordinates) and a bitonic function exists for response rate. Based on these findings, the present analysis applied the unit-price concept to those studies of reinforcer magnitude and drug self-administration that examined the effects of reinforcer magnitude on response rate using simple schedules of reinforcement (e.g., fixed-ratio schedule). This resulted in three findings: (a) Reinforcer-magnitude manipulations and schedule manipulations interact in a manner that can be quantified in terms of unit price as benefit and cost factors, respectively; (b) different reinforcer-magnitude manipulations are functionally interchangeable as benefit factors in the unit-price ratio; and (c) these conclusions appear warranted despite the differences in reinforcers (food or drug), species (dogs, monkeys, or rats), and schedules (interval or ratio), and despite the fact that these studies were not designed for a unit-price analysis. In methodological terms, these results provide further evidence that employing the unit-price concept is a parsimonious method for examining the effects of reinforcer magnitude. In theoretical terms, these results suggest that a single process may underlie the effect of combined reinforcer-magnitude and schedule manipulations.     

Phenomenology in Russia: The contribution of Gustav Shpet

Gustav Shpet,Appearance and Sense: Phenomenology as the Fundamental Science and Its Problems, Trans. Thomas Nemeth (Dordrecht, Boston, London: Kluwer Academic Publishers, 1991). xxxi+189 pages. $94.00. (Page references to this work are given in parentheses in the text.)     

Coming to terms with stress: Effects of stress location in sentence processing

The purpose of this research was to determine the role of syllabic stress in language processing during the early on-line processing of speech and later in the representation of a sentence in memory. Experiment 1 used a syllable monitoring task while Experiment 3 used a probe task in which subjects heard a sentence and then were asked to determine whether a probe syllable had occurred in the sentence. In the monitoring task, stressed syllables were detected more rapidly in word-initial position, but unstressed syllables were detected more rapidly in word-final position. Stress facilitation in initial syllables was strongly related to high relative F0, but not to changes in perceived vowel quality as assessed in Experiment 2. This pattern is interpreted as evidence that lexical stress is used on-line to guide lexical access and/or lexical segmentation. The probe task of Experiment 3 showed stress facilitation in both positions, indicating that stress is independently retained in the postperceptual representation of a sentence.The research reported in this paper was supported by grant 80-0416 to Harvard University (Peter C. Gordon, Principal Investigator) from the Air Force Office of Scientific Research Life Sciences Directorate. We thank Chris Thurber for his extensive and competent assistance in testing subjects and making acoustic measurements, and Jay Rueckl for comments on an earlier version of this paper     

Relation of parental support and control to adolescents' externalizing symptomatology and substance use: A longitudinal examination of curvilinear effects

Past research has generated inconsistent findings regarding the relation of parental control and support to adolescent problem behaviors. Using two waves of data collected 1 year apart, the current study examined the influence of parental control and support on adolescents' externalizing symptoms, alcohol use, and illicit substance use. A sample of adolescents and their parents (@#@ N =454) was studied, within which approximately half of the adolescents were at high risk because of parental alcoholism. Multipleregression analyses of crosssectional data showed a negative quadratic relation between parental control and adolescent externalizing symptomatology, and between parental control and adolescent illicit substance use. Parental control had a negative linear relation to adolescent alcohol use. Parental support showed a negative quadratic relation to adolescent illicit substance use, and negative linear relations to adolescent alcohol use and externalizing symptoms. Although longitudinally adjusted contemporaneous results were consistent with crosssectional findings, parental support and control were prospectively related only to adolescent alcohol use. The quadratic relations suggest that adolescents who receive either extreme of parental support or control are at risk for problem behaviors.     

WHAT MATTERS IN SURVIVAL?

Abstract: I examine Derek Parfit's claim that it doesn't matter whether he survives in the future, if someone survives who is psychologically connected to him by “Relation R.” Thus, were his body to perish and be replaced by an exact duplicate, both physically and psychologically identical to him, this would be just as good as “ordinary” survival. Parfit takes the corollary view that replacement of loved ones by exact duplicates is no loss. In contrast, Peter Unger argues that we place nontransferable value in the lives of individual persons. I argue that the question of the preferability of Relation R over identity is unanswerable at present, as such hypothetical situations are too far removed from our experience to allow any reliable responses. I contrast cases involving artifacts, where we can make informed judgments concerning whether a given object's value would be transferred to a duplicate.     

Hypermnesia in free recall and cued recall

In three experiments, categorized lists and both free recall and cued recall tests were used to examine hypermnesia. In Experiment 1, materials were drawn from obvious and nonobvious categories in an attempt to vary the amount of relational processing at encoding. The study materials in Experiment 2 consisted of a long word list that comprised several exemplars from each of a number of common categories. In Experiment 3, a single exemplar was drawn from each of 45 categories. In each experiment, similar magnitudes of hypermnesia were obtained on free and cued recall tests. Examination of the specific items recalled across tests indicated that similar processes underlie the hypermnesic effect for both test conditions. Implications of the results for extant accounts of the hypermnesic effect are discussed. It is concluded that the dynamics of retrieval processes change in a systematic fashion across repeated tests and the retention interval following study and that an adequate account of the nature of these changes in retrieval dynamics is essential to our understanding of hypermnesia and related phenomena.     

Anticipated outgroup evaluations and intergroup bias

A study is reported that tests the hypothesis that group members exhibit intergroup bias in response to the belief that outsiders will discriminate against them. To this end, two experimental conditions are included in which subjects anticipate either biased evaluations or fair evaluations respectively. In a control condition, subjects do not expect to be evaluated from an external source. Results indicated, as expected, that those who anticipated biased evaluations from an outgroup exhibited bias themselves, while those who anticipated fair evaluations exhibited outgroup favouritism. The fact that control subjects exhibited the same degree of bias as those who anticipated biased evaluations from the outgroup poses some difficulties for the hypothesized connection between anticipated discrimination and intergoup bias. Thus, it appears that intergroup bias is the rule and not the exception in an intergroup context. Nevertheless, it is clear that anticipated evaluations of outgroup members can effect intergroup bias.     

Sensitivity of persons with hearing impairment to visual emotional expression — compensation or deficit?

The research examined whether subjects with hearing impairment would differ from normal hearing subjects in their ability to decode emotions from video stimuli (48 video takes in which two actors portrayed six different emotions). Studies in tactile and visual perception lead one to expect deficits, while there is also some evidence for compensation. Twenty-six subjects with hearing impairment and 26 matched normal hearing subjects participated (average age = 25.5 years; nine female, 17 male subjects in each group). Results indicate that in general subjects with hearing impairment were slightly less successful in decoding emotions from the visual stimuli than the normal hearing subjects. A comparison between highly (loss > 60–90 dBA) and moderately (loss about 30–60 dBA) impaired subjects on the other hand indicated poorer emotion decoding only for the moderately impaired group. Post-hoc analyses indicated that these effects were specific to males. Results are discussed with respect to compensation versus deficit, and with respect to issues of training.