125 years of perceptual-motor skill research

This article celebrates the contribution that the American Journal of Psychology (AJP) has made to the area of perceptual-motor skill over its 125-year history. We highlight the articles published in AJP and trace the technical and theoretical developments that stem from this groundbreaking work. Included in our overview are AJP articles on the excitability of the motor system, motor learning, adaptation to visual rearrangement, the ecological approach to perception and action, and the measurement of human handedness. We conclude by identifying a number of areas associated with perceptual-motor skill where AJP continues to make an important contribution.     

Your heart makes my heart move: Cues of social connectedness cause shared emotions and physiological states among strangers

Two experiments tested the hypothesis that cues of social connectedness could lead even new interaction partners to experience shared emotional and physiological states. In Experiment 1, a confederate prepared for a stress-inducing task. Participants who had been led to feel socially connected to the confederate reported feeling greater stress than participants who had not. In Experiment 2, a confederate ran vigorously in place. Socially-connected participants had greater cardiovascular reactivity (heart rate and blood pressure) than controls. Each study held constant exposure to the confederate. The results suggest that the sharing of psychological and physiological states does not occur only between long-standing relationship partners, but can also result from even subtle experiences of social connectedness. These findings illustrate the dynamic and fluid ways in which important aspects of self can change in response to cues of social relatedness.     

Evidence and Knowledge

According to Williamson, your evidence consists of all and only what you know (E = K). According to his critics, it doesn’t. While E = K calls for revision, the revisions it calls for are minor. E = K gets this much right. Only true propositions can constitute evidence and anything you know non-inferentially is part of your evidence. In this paper, I defend these two theses about evidence and its possession from Williamson’s critics who think we should break more radically from E = K.     

Social eye gaze modulates processing of speech and co-speech gesture

In human face-to-face communication, language comprehension is a multi-modal, situated activity. However, little is known about how we combine information from different modalities during comprehension, and how perceived communicative intentions, often signaled through visual signals, influence this process. We explored this question by simulating a multi-party communication context in which a speaker alternated her gaze between two recipients. Participants viewed speech-only or speech + gesture object-related messages when being addressed (direct gaze) or unaddressed (gaze averted to other participant). They were then asked to choose which of two object images matched the speaker’s preceding message. Unaddressed recipients responded significantly more slowly than addressees for speech-only utterances. However, perceiving the same speech accompanied by gestures sped unaddressed recipients up to a level identical to that of addressees. That is, when unaddressed recipients’ speech processing suffers, gestures can enhance the comprehension of a speaker’s message. We discuss our findings with respect to two hypotheses attempting to account for how social eye gaze may modulate multi-modal language comprehension.     

Family Therapy with Couples and Individuals with Parkinson’s Disease

Family therapists are increasingly called upon to work with individuals and families with medical issues, but often do not have sufficient background on the issue to be most helpful. The purpose of this paper is to help family therapists understand Parkinson’s Disease (PD) and its impact on the individual and his or her family. PD is the second most prevalent neurodegenerative disorder in the United States, following Alzheimer’s disease (Hirtz et al., Neurology 68:326–337, 2007). According to the Parkinson’s Disease Foundation, approximately 60,000 individuals are diagnosed with PD every year, and approximately one million Americans are currently living with PD. In this paper, we provide an overview of PD based on research and the second author’s many years of providing services for individuals with PD, as well as offer specific recommendations for providing family therapy using narrative, solution-focused and emotionally focused therapy based on the first author’s work as a family therapist with individuals, groups, and couples dealing with PD.     

Non‐Bayesian Noun Generalization in 3‐ to 5‐Year‐Old Children: Probing the Role of Prior Knowledge in the Suspicious Coincidence Effect

It is unclear how children learn labels for multiple overlapping categories such as “Labrador,” “dog,” and “animal.” Xu and Tenenbaum (2007a) suggested that learners infer correct meanings with the help of Bayesian inference. They instantiated these claims in a Bayesian model, which they tested with preschoolers and adults. Here, we report data testing a developmental prediction of the Bayesian model—that more knowledge should lead to narrower category inferences when presented with multiple subordinate exemplars. Two experiments did not support this prediction. Children with more category knowledge showed broader generalization when presented with multiple subordinate exemplars, compared to less knowledgeable children and adults. This implies a U‐shaped developmental trend. The Bayesian model was not able to account for these data, even with inputs that reflected the similarity judgments of children. We discuss implications for the Bayesian model, including a combined Bayesian/morphological knowledge account that could explain the demonstrated U‐shaped trend.     

Heterogeneity in verbal memory: a marker of preclinical Alzheimer's disease?

Demonstrations of memory changes in those at risk for Alzheimer's disease by the presence of the APOE e4 allele have been inconsistent to date. The present study went beyond traditional analyses of central tendency (i.e., group differences on mean test scores) and also conducted distribution analyses to search for subtle cognitive differences in subgroups of normal-functioning elderly persons with the APOE e4 genotype. The results of the study revealed that (a) the e4 and non-e4 groups failed to differ in terms of their mean scores on tests of memory and verbal skills; and (b) relative to the non-e4 group, the e4 subjects had significantly greater heterogeneity of variance on the memory measures but not on fundamental verbal skills. Logistic regression analyses indicated that the discrepancy in scores on the memory measures was a significant predictor of genotype group membership (82% correct classification rate). Implications of these findings for the detection of a preclinical phase of AD are discussed.     

Aging and the perception of 3-D shape from dynamic patterns of binocular disparity

In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative.