Parsing silhouettes: The short-cut rule

Many researchers have proposed that, for the purpose of recognition, human vision parses shapes into component parts. Precisely how is not yet known. The minima rule for silhouettes (Hoffman & Richards, 1984) defines boundary points at which to parse but does not tell how to use these points to cut silhouettes and, therefore, does not tell what the parts are. In this paper, we propose the short-cut rule, which states that, other things being equal, human vision prefers to use the shortest possible cuts to parse silhouettes. We motivate this rule, and the well-known Petter’s rule for modal completion, by the principle of transversality. We present five psychophysical experiments that test the short-cut rule, show that it successfully predicts part cuts that connect boundary points given by the minima rule, and show that it can also create new boundary points.     

The Prediction of Negative Events Associated with Anxiety and Dietary Restraint: A Test of the Content Specificity Hypothesis

The prediction of future negative events was studied in a sample of undergraduate students varying on measures of anxiety and dietary restraint. Cognitive theories of psychopathology hypothesize that the emotional concerns of an individual determine which types of information are most often cognitively processed with a biased interpretation. This prediction has generally been called the content specificity hypothesis. Based upon this aspect of cognitive theory, we hypothesized that a high level of trait anxiety would be associated with higher ratings of the probability of future physically threatening events. In addition, it was hypothesized that a high level of dietary restraint would be associated with lower ratings of the probability of future occurrences of overeating. The results of the study supported these hypotheses. These prediction biases were found to be more pronounced in women, as compared to men. The findings were interpreted as supportive of the content specificity hypothesis.     

Testing the Idea of Distinct Storage Mechanisms in Memory

This paper sets out quantitative foundations for testing the idea that memory is served by two distinct storage mechanisms, a short-term and a separate long-term store, using data from the single-trial free-recall experiment by Murdock and Okada (1970). In single-trial free recall one can observe which word is recalled next and how long that recall takes, but that is all. So justification for two separate stores must turn either on the probabilities of recall, or on the latencies, for particular serial positions in the stimulus list. (a) Nearly one-third of all recalls after the first are successors (Word n+1 immediately following recall of Word n). So recall is dominated, not by absolute serial position (as a short-term store would require), but by position relative to the preceding recall. (b) To a first approximation, all first recalls have the same latency distribution except for Word 1. A common latency distribution is compatible with a single store. An explanation is offered why Word 1 should take longer, in which Word 1 is the second retrieval from a common store. The idea of two separate stores appears to lack experimental support.     

Effects of Directed Thinking on Intentions to Engage in Beneficial Activities: Actions Versus Reasons1

An important application of psychological principles involves increasing intentions to engage in activities that, although admittedly beneficial, are often not initially appealing (e.g., studying, quitting smoking, dieting). The present study tests the utility of directed thinking as a tool for eliciting intentions to engage in such activities. Undergraduate students were directed to think either about the reasons why people should find studying enjoyable or about the actions that people might take to make studying enjoyable. Regardless of whether they thought as individuals or in cooperating dyads, students who thought about actions later reported greater intentions to spend time studying than did students who thought about reasons. The results have both theoretical and practical significance.     

The Effects of Feedback Equivocality on Escalation of Commitment: An Empirical Investigation of Decision Dilemma Theory1

The effects of feedback equivocality on escalation of commitment were examined in a laboratory study. Subjects had multiple opportunities to allocate money to market a software product. During the initial phase, subjects received feedback that was of either low or high equivocality. Half of the subjects in each equivocality level were given a standard by which to judge the feedback. In the second phase, all subjects received negative feedback. Consistent with Bowen's (1987) decision dilemma theory, subjects who received low equivocality feedback did not escalate allocations, and subjects who received high equivocal feedback escalated allocations. The presence of a standard or goal attenuated escalation. These results are consonant with a dynamic, temporally based account of escalation and are discussed in a synthesis of the literatures in behavior analysis, economics, forecasting, and psychology.     

Couple‐based Intervention for Depression: An Effectiveness Study in the National Health Service in England

This study represents an effectiveness study and service evaluation of a cognitive behavioral, couple‐based treatment for depression (BCT‐D) provided in London services that are part of the “Improving Access to Psychological Therapies” (IAPT) program in England. Twenty‐three therapists in community clinics were trained in BCT‐D during a 5‐day workshop, followed by monthly group supervision for 1 year. The BCT‐D treatment outcome findings are based on 63 couples in which at least one partner was depressed and elected to receive BCT‐D. Eighty‐five percent of couples also demonstrated relationship distress, and 49% of the nonclient partners also met caseness for depression or anxiety. Findings demonstrated a recovery rate of 57% with BCT‐D, compared to 41% for all IAPT treatments for depression in London. Nonclient partners who met caseness demonstrated a 48% recovery rate with BCT‐D, although they were not the focus of treatment. BCT‐D was equally effective for clients regardless of the clinical status of the nonclient partner, suggesting its effectiveness in assisting both members of the couple simultaneously. Likewise, treatment was equally effective whether or not both partners reported relationship distress. The findings are promising regarding the successful application of BCT‐D in routine clinical settings.     

Is it sometimes better to receive than to give? Preferences for receiver roles over proposer roles in consumer behavior ultimatums

In the context of purchasing ultimatums, consumers may dislike the freedom of choice that comes with proposing offers due to their awareness that the other party may have better information than they do and the fact that the attractiveness of outside alternatives is uncertain. Indeed, across three studies, we find that people prefer to receive rather than propose offers. In Study 1, proposers reached fewer agreements and experienced less favorable attitudes (e.g., satisfaction, fairness, recommendation intentions), particularly when their offers were rejected. In Study 2, proposers experienced more uncertainty and cognitive depletion as compared to receivers, again particularly if the proposed offer was rejected. In Study 3, role preferences were explained by the existence of higher regret in the proposer role, particularly if the proposed offer was rejected. We conclude with a consideration of the theoretical and practical implications of our research for scholars, customers, and service providers.     

Relationship between reaction time variability and motor skill development in ADHD

Slower and more variable reaction times to computerized tasks have been documented in children diagnosed with attention deficit/hyperactivity disorder (ADHD). Recent research supports a role for attentional lapses in generating abnormally variable and slow responses. However, given the association between ADHD and impairments in motor control, we hypothesized that slower or more variable reaction times might also correlate with motor development. The aim of this case-control study was to explore the relationship between motor function, reaction speed and variability, and ADHD. After comprehensive educational and clinical assessments, motor skill development was evaluated in 35 children ages 9 to 14 (19 with ADHD) using the Physical and Neurological Examination for Subtle Signs (PANESS) test battery. Finger-sequencing speed and variability were quantified with goniometers. Reaction times were measured with 20 trials each of computerized simple and choice (binary) tasks. Compared to healthy controls, children with ADHD had slower and more variable reaction times, and these findings correlated with impaired motor development (PANESS) and slow and variable finger sequencing (goniometers). Further studies of motor development in ADHD may identify factors influencing speed and variability of reaction times.