Is the cerebellum a smith predictor?

The motor system may use internal predictive models of the motor apparatus to achieve better control than would be possible by negative feedback. Several theories have proposed that the cerebellum may form these predictive representations. In this article, we review these theories and try to unify them by reference to an engineering control model known as a Smith Predictor. We suggest that the cerebellum forms two types of internal model. One model is a forward predictive model of the motor apparatus (e.g., limb and muscle), providing a rapid prediction of the sensory consequences of each movement. The second model is of the time delays in the control loop (due to receptor and effector delays, axonal conductances, and cognitive processing delays). This model delays a copy of the rapid prediction so that it can be compared in temporal register with actual sensory feedback from the movement. The result of this comparison is used both to correct for errors in performance and as a training signal to learn the first model. We discuss evidence that the cerebellum could form both of these models and suggest that the cerebellum may hold at least two separate Smith Predictors. One, in the lateral cerebellum, would predict the movement outcome in visual, egocentric, or peripersonal coordinates. Another, in the intermediate cerebellum, would predict the consequences in motor coordinates. Generalization of the Smith Predictor theory is discussed in light of cerebellar involvement in nonmotor control systems, including autonomic functions and cognition.     

Is self-esteem the primary predictor of disordered eating?

This study examined whether self-esteem is the primary predictor of disordered eating. A survey measured levels of self-esteem and a variety of other health behaviors in 196 male and 263 female undergraduate students. We conducted stepwise regressions to determine which of several variables (self-esteem, high stress, poor coping skills, maladaptive perfectionism, gender) best predicted disordered eating. The results indicated that self-esteem was the secondary predictor for bulimia, drive for thinness, and body dissatisfaction. Future research should further investigate how self-esteem interacts with other predictor variables to better determine the relationship between self-esteem and disordered eating.     

Is the brain an effective Turing machine or a finite-state machine?

Summary A theorem presented by Hornik, Stinchcombe, and White (1989) suggested the possibility that connectionist networks could be effectively Turing machines. Levelt (1990) argued that the theorem of Hornik et al. only implies that networks are finite-state machines and are therefore not capable of generating the very unlimited productivity of symbol systems. Yet it can be argued that all real machines, including the brain, are finite-state machines. If so, no real machine actually possesses the very unlimited productivity of symbol systems. So any model of actual behaviour should capture the limitations on productivity inherent in the situation. Thus connectionist networks can be valuable models in psychology, precisely because they are finite-state machines.     

Is Satan a Lover of the Good?

There are, apparently, two inherited stories of intentional action. On the motivational story, intentional agents are pursuers of goals. On the evaluative story, intentional agents are pursuers of value. In a spirit of unification, we might try to supplement the motivational story with the evaluative one – or even collapse the former into the latter. The problem with such moves is that they cannot accomodate certain pathologies of agency. Thus, they convert apparently perverse agents – like Satan and self-haters – into closet lovers of the good. I argue that pathological agents like Satan and self-haters are not lovers of the good. They are just lovers of success in action. We can make sense of such agents as practical reasoners because the cares that constitute us as practical reasoners are plural.     

Is dual-task slowing instruction dependent?

When 2 tasks must be performed concurrently, each requiring a choice of response, dual-task slowing is typically found. However, E. H. Schumacher et al. (1997) reported that dual-task slowing can be eliminated when equal priority is assigned to each task. Experiment 1 largely confirmed this with the same tasks as Schumacher et al. (tasks using stimulus-response combinations of visual-manual and auditory-vocal pairings). Experiment 2 retained the equal-priority instructions but switched the task pairings (to visual-vocal and auditory-manual); substantial dual-task slowing occurred. Experiment 3 used the same two response sets but only a single stimulus; slowing was again obtained despite equal priority instructions. Equalizing task priority was not sufficient to eliminate interference; relatively unusual cases in which dual-task interference is eliminated seem to depend on task-specific features.     

Is choice a reliable predictor of choice? A comment on Sagarin and Skowronski

In a recent working paper, Chen (2008) argues that a methodology central to the cognitive dissonance literature (the free-choice paradigm) has suffered from an inability to separately measure how much choices affect people’s preferences, and how much they simply reflect those preferences, by failing to fully control for the fact that subjects tend to choose goods they prefer. Although Sagarin and Skowronski concede this, they discount Chen’s argument, claiming that for revealed preferences to completely account for observed choice-effects the relationship between choice and preference would have to be unrealistically high. In this comment, we argue that their critique both misses the crux of Chen’s analysis, and is incorrect. Specifically, to properly test whether choices affect preferences, it is essential that researchers experimentally control for revealed preferences rather than speculate how much of a role they may play. Moreover, Sagarin and Skowronski’s critique rests on two fundamental errors—a misunderstanding of the function of the null-hypothesis and a misunderstanding of preference-measurement psychometrics. These errors leads Sagarin and Skowronski to suggest alternative experimental designs which while a good first step, do not address the problems identified in Chen (2008).     

Is the Reasonable Person a Person of Virtue?

Res Publica - The ‘reasonable person standard’ (RPS) is often called on in difficult legal cases as the last resource to be appealed to when other solutions run out. Its complexity...     

Mothers of high-risk infants: Is their initial use of early intervention a predictor of later coping?

In a program for high-risk and handicapped infants that began at hospital discharge, mothers' initial use of intervention visits was investigated as a predictor of maternal functioning 9 months later. Measures included ventilation and advice seeking in the first month and 9-month maternal mood, coping, HOME scores, and use of intervention. Early ventilation and advice seeking were related significantly to mothers' self-reported confusion, but not to staff ratings of maternal mood. No significant relationships were found between early use of intervention and later coping, HOME scores, or use of intervention. Results are discussed in terms of mothers' generally good adaptation and the need for caution in drawing conclusions from their behavior soon after the birth of a high-risk or handicapped child.     

Children and the Test of Memory Malingering: Is one trial enough?

There is a growing body of research suggesting that the first trial of the TOMM may provide an accurate screener of effort in children. During neuropsychological assessments, some circumstances result in only one completed trial of the TOMM. Research on adults reflects that passing scores on Trial 1 (based on Trial 2 cutoff) are highly predictive of passing scores on Trial 2 and the TOMM overall. Pediatric research found that 100% of children and adolescents who passed Trial 1 of the TOMM also passed Trial 2. Our research hypothesis is that children who pass Trial 1 will also pass Trial 2. Data from 75 clinically diagnosed children (ages 6–18 years) found that 64% performed above the published adult TOMM cutoff on Trial 1. All children who passed Trial 1 also passed Trial 2 suggesting support for the research hypothesis. Sensitivity was 1.0, specificity was 0.72, positive predictive value was .33, and negative predictive value was 1.0. These findings suggest that in this sample, the children who performed above the Trial 2 cutoff on Trial 1 also all passed Trial 2 (so there were no false negatives, thus a perfect sensitivity and negative predictive value). Of the 36% of children who did not pass the Trial 1 cutoff, 67% passed on Trial 2. Data clearly support that children passing Trial 1 have a high likelihood of passing Trial 2, thus drawing conclusions about performance validity after passing Trial 1. Conclusions after failing Trial 1 require further investigation.     

Is pain-related fear a predictor of somatosensory hypervigilance in chronic low back pain patients?

Pain-related fear has been found to be associated with increased disability and increased pain perception in patients with chronic low back pain. A possible mechanism by which pain-related fear could lead to increased pain perception is heightened attention to somatosensory sensations. In the present study, chronic pain patients reporting either a high or low level of pain related fear and control participants performed an auditory reaction time task, while occasionally non-painful electrical stimuli--accompanied by threatening instructions--were given to the arm or back. In the primary task condition, participants had to perform the auditory task while ignoring the electrical stimuli. Next, the task was presented under dual task conditions in which participants had to respond both to tones as well as to detection of electrical stimuli. It was hypothesized that for the primary task, high fearful patients would show greater disruption of performance on the auditory task than low fearful patients and controls when stimuli were presented to the back. For the dual task, slower reaction times for the auditory task, in combination with faster detection of electrical stimuli was expected. The hypotheses were not confirmed but patients scoring high on pain-related fear did show an overall increase in reaction time for all conditions of the primary task, with or without simultaneous stimulation. Regression analyses demonstrated that high pain-related fear was associated with increased reaction time to tones both in patients and healthy controls, and that within patients pain-related fear was a better predictor of reaction time to tones than present pain intensity. The findings may be interpreted as showing that patients with elevated levels of pain-related fear habitually attend to somatic sensations, giving less priority to other attention-demanding tasks.     

Is the Counselor a Woman?

The 16 PF was administered to 75 male and 43 female high school counselors to determine whether they manifested the femininity (loving receptivity) and the masculinity (potency) that have been said to be important to the counseling role. The men differed significantly from male norms in the feminine direction on warmth, tender-mindedness, and trust. They deviated significantly in the direction of potency on brightness, ego strength, adequacy, and tranquility, but away from potency on caution and group-dependency. The women differed significantly from female norms in the feminine direction only on trust, but in the masculine direction on assertiveness, venturesomeness, and practicality. They deviated significantly in the direction of personal strength on brightness, ego strength, superego strength, adequacy, experimentation, and tranquility.     

Is the allure of self-esteem a mirage after all?

Comments on the original article "Do people's self-views matter? Self-concept and self-esteem in everyday life," by W. B. Swann, Jr., C. Chang-Schneider, and K. L. McClarty. Swann et al argued that people's self-views, and their global self-esteem in particular, yield a suite of behavioral effects that are beneficial to the individual and to society at large. The Swann et al article is the latest link in a debate on the causal utility of self-esteem. Specifically, the article is a reply to a report published by the American Psychological Society Task Force on Self-Esteem (Baumeister, Campbell, Krueger, & Vohs, 2003). As members of that task force, the current authors wish to express their broad agreement with Swann et al. At the same time, in the comment presented here, they clarify pockets of disagreement.     

Is Humility a Virtue in the Context of Sport?

I define humility as a virtue that includes both proper self‐assessment and a self‐lowering other‐centeredness. I then argue that humility, so understood, is a virtue in the context of sport, for several reasons. Humility is a component of sportspersonship, deters egoism in sport, fuels athletic aspiration and risk‐taking, fosters athletic forms of self‐knowledge, decreases the likelihood of an athlete seeking to strongly humiliate her opponents or be weakly humiliated by them, and can motivate an athlete to achieve greater levels of excellence in her sport. In the context of team sports, humility can contribute to an athlete being a better teammate, foster unity amidst diversity within a team, and contribute to the overall moral and athletic excellence of a team. I also argue that an individual who is truly the world's greatest athlete can know and communicate this truth, while remaining humble.     

Is the perceived present a predictive model of the objective present?

ABSTRACT

Processing latencies for coherent, high level percepts in vision are at least 100?ms and possibly as much as 500?ms. Processing latencies are less in other modalities, but still significant. This seems to imply that perception lags behind reality by an amount equal to the processing latency. It has been proposed that the brain can compensate for perceptual processing latencies by using the most recent available information to extrapolate forward, thereby constructing a model of what the world beyond the senses is like now. The present paper reviews several lines of evidence relating to this hypothesis, including the flash-lag effect, motion-induced position shifts, representational momentum, static visual illusions, and motion extrapolation at the retina. There are alternative explanations for most of the results but there are some findings for which no competing explanation has yet been proposed. Collectively, the evidence for extrapolation to the present is suggestive but not yet conclusive. An alternative account of compensation for processing latencies, based on the hypothesis of rapid emergence of percepts, is proposed.     

Is the learn unit a fundamental measure of pedagogy?

We propose a measure of teaching, the learn unit, that explicitly describes the interaction between teachers and their students. The theoretical, educational research, and applied behavior analysis literatures all converge on the learn unit as a fundamental measure of teaching. The theoretical literature proposes the construct of the interlocking operant and embraces verbal behavior, social interaction, and translations of psychological constructs into complex theoretical respondent-operant interactions and behavior-behavior relations. Research findings in education and applied behavior analysis on engaged academic time, opportunity to respond, active student responding, teacher-student responding, student-teacher responding, tutor-tutee responding, tutee-tutor responding, and verbal episodes between individuals all support a measure of interlocking responses. More recently, research analyzing the components of both the students' and teachers' behavior suggests that the learn unit is the strongest predictor of effective teaching. Finally, we propose applications of the learn unit to other issues in pedagogy not yet researched and the relation of learn units to the verbal behavior of students.     

Is the number of trials a primary determinant of conditioned responding?

Acquisition of conditioned responding is thought to be determined by the number of pairings of a conditioned stimulus (CS) and an unconditioned stimulus (US). However, it is possible that acquisition is primarily determined not by the number of trials but rather by quantities that often correlate with the number of trials, such as cumulative intertrial interval (ITI) and the number of sessions. Four experiments examined whether the number of trials has an effect on acquisition of conditioned responding, once cumulative ITI and number of sessions are equated. Results of the experiments with rats and mice favor the hypothesis that over an eightfold range, variation in number of CS-US pairings has little effect. It is suggested that learning curves might more accurately be plotted across cumulative ITI or number of sessions, and not across number of trials. Results pose a challenge to trial-centered accounts of conditioning, as demonstrated by simulations of the Rescorla-Wagner model, a simplified version of Wagner's standard operating procedure model (SOP), and Stout & Miller's sometimes competing retrieval model (SOCR). A time-centered account, rate estimation theory (RET), predicts the main finding but has trouble with other aspects of the learning process more easily accommodated by trial-centered models.     

Is the Ambivalence a Sign of the Multiple-Self Nature of the Human Being? Interdisciplinary Remarks

Ambivalence is a constituent feature of human beings. The aim of this article is to systematise the fundamental sources of ambivalence (neuropsychic, socio-cultural and situational) and highlight that ambivalence can be considered as an external sign or manifestation of a complex and multiple internal human nature; that is, a human being constituted by multiple selves. In this paper the self is viewed as a principle of organization and integration for action, that is, as a complex neurological process and not as a static entity. The purpose is to show how by assuming ambivalence and the multiple-self, social and anthropological theories can offer a more realistic view of human beings.     

Self-rated adjustment and sex-typing on the Bem Sex-Role Inventory: Is masculinity the primary predictor of adjustment?

Questions concerning the relationship between self-rated adjustment and the Bem Sex-Role Inventory (BSRI) were examined in two studies. In Study I, whether sex-typing was defined by Bem's original t-test criterion or the newer median-split criterion, superior adjustment was associated with androgynous vs. traditional typing only among women, not men. Also in conflict with the androgyny position, adjustment differences among sex-types were accounted for by differences in masculinity, not in femininity or androgyny per se. The greater contribution of masculinity vs. femininity to self-rated adjustment may be exaggerated because BSRI femininity includes items which do not load on a unidimensional femininity factor. In Study II, inspection of these unrelated items suggested that they reduce the desirability of BSRI femininity, thereby reducing its relationship to adjustment. Comparisons between standard BSRI scoring and an alternative based on unidimensional subscales revealed that the alternative femininity subscale was judged to be more desirable, and it reduced the degree of difference between masculinity and femininity in their relationships to adjustment. Superior adjustment, however, was again associated with androgynous vs. traditional sex-typing only among women, and adjustment differences among sex-types were again accounted for by differences in masculinity.The authors acknowledge the assistance of the following persons who helped in the administration, scoring, or preparation of questionnaire materials: Jill Jamison, Eric Isberg, Kay Peter, Steve Zalinger, Walter Davis, James Ball, Mark Jensen, and Heidi Sanft. Correspondence should addressed to Dr. Louise Silvern, Psychology Department, University of Colorado, Boulder, Colorado 80309.