Manipulating perception versus action in recalibration tasks

We conducted six experiments to examine how manipulating perception versus action affects perception–action recalibration in real and imagined blindfolded walking tasks. Participants first performed a distance estimation task (pretest) and then walked through an immersive virtual environment on a treadmill for 10 min. Participants then repeated the distance estimation task (posttest), the results of which were compared with their pretest performance. In Experiments 1a, 2a, and 3a, participants walked at a normal speed during recalibration, but the rate of visual motion was either twice as fast or half as fast as the participants' walking speed. In Experiments 1b, 2b, and 3b, the rate of visual motion was kept constant, but participants walked at either a faster or a slower speed. During pre- and posttest, we used either a blindfolded walking distance estimation task or an imagined walking distance estimation task. Additionally, participants performed the pretest and posttest distance estimation tasks in either the real environment or the virtual environment. With blindfolded walking as the distance estimation task for pre- and posttest, we found a recalibration effect when either the rate of visual motion or the walking speed was manipulated during the recalibration phase. With imagined walking as the distance estimation task, we found a recalibration effect when the rate of visual motion was manipulated, but not when the walking speed was manipulated in both the real environment and the virtual environment. Discussion focuses on how spatial-updating processes operate on perception and action and on representation and action.     

Prism adaptation in alternately exposed hands

We assessed intermanual transfer of the proprioceptive realignment aftereffects of prism adaptation in right-handers by examining alternate target pointing with the two hands for 40 successive trials, 20 with each hand. Adaptation for the right hand was not different as a function of exposure sequence order or postexposure test order, in contrast with adaptation for the left hand. Adaptation was greater for the left hand when the right hand started the alternate pointing than when the sequence of target-pointing movements started with the left hand. Also, the largest left-hand adaptation appeared when that hand was tested first after exposure. Terminal error during exposure varied in cycles for the two hands, converging on zero when the right hand led, but no difference appeared between the two hands when the left hand led. These results suggest that transfer of proprioceptive realignment occurs from the right to the left hand during both exposure and postexposure testing. Such transfer reflects the process of maintaining spatial alignment between the two hands. Normally, the left hand appears to be calibrated with the right-hand spatial map, and when the two hands are misaligned, the left-hand spatial map is realigned with the right-hand spatial map.     

Inhibitory processes and the control of memory retrieval

People are often confronted with reminders of things they would prefer not to think about. When this happens, they often attempt to put the unwanted memories out of awareness. Recent research shows that the capacity to suppress distracting traces is mediated by executive-control processes that are analogous to those involved in overriding prepotent motor responses, and it is these processes that cause persisting memory failures for the suppressed items. There is evidence that memory retrieval and motor tasks that are likely to demand executive control recruit overlapping neural mechanisms, suggesting that a common process mediates control in these domains. Together, these findings indicate that memory failures often arise from the mechanisms that lie at the heart of our capacity to influence the focus of thought.     

Presurgical MMPI-2 Cluster Profiles Predict 1-Year Low-Back Surgery Outcomes

The primary purpose of this study was to examine whether empirically derived cluster profiles based on scores from the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) predicted outcomes of surgery at 1 year for patients with low-back pain. On the basis of hierarchical cluster analysis of presurgery MMPI-2 scores for 60 patients, three interpretable and significant subgroups were formed. These consisted of a pathological/neurotic type, a double V-code type, and a normal type. The patents in the normal type were significantly more likely to report beneficial outcomes of surgery in terms of disability and pain than those in the other 2 types. These findings extend previous research and suggest (1) low-back surgery candidates are heterogeneous in their psychological profiles, and (2) MMPI-2 profiles are predictive of low-back surgery outcome. Future research should focus on identifying physiological substrates for these distinct profiles and investigating the effectiveness of presurgical psychological interventions based on profile type.     

Why Can't Psychology Get a Stamp?

In the latter half of the 1980s as the centennial of the American Psychological Association approached, the APA organized an effort to persuade the United States Postal Service to issue a stamp recognizing the contributions of psychology to the quality of life in America. That effort failed. The history of psychology and psychologists represented on stamps worldwide is described, as is a recent attempt to create a United States stamp focused on mental health. The failure of psychology to achieve recognition on a U. S. stamp is discussed in the context of the stigma of mental illness and the public image of psychology.     

Narrative models of action and interaction

This paper explores some issues which a humanlike story system ought to encompass, but which are usually not in the main focus of narrative models since Propp. We argue that knowledge about actions and interactions can account not only for how stories are constructed, but also for why some stories are more interesting and enduring than others. We analyze a traditional English folktale in these terms, and show how classes of surface expressions make recoverable the underlying structures and dependencies that schema-based understanders comprise.