Semantic processing without conscious identification: evidence from event-related potentials

Three event-related potential (ERP) experiments examined whether semantic content can be accessed from visually presented words that cannot be consciously identified. Category labels were shown to participants, followed by masked, briefly exposed words that were either exemplars of the category or not exemplars. The task was to verify the category, by guessing if necessary, and to identify the word, naming it if possible. Exposure durations were selected to allow identification in approximately half the trials. For identified words, there was a marked difference in the ERP response between in-category and out-of-category words because of an N400 component. For unidentified words, there was a similar although smaller difference. Conscious identification was defined using a variety of approaches: verbal report, 6-alternative forced choice, and binary categorization (in the context of the regression method; A. G. Greenwald, M. R. Klinger, & E. S. Schuh, 1995). By any definition, ERPs for unidentified words showed evidence of semantic processing. In addition, there were differences in the neuronal populations recruited to process above-threshold versus below-threshold words, suggesting qualitative differences.     

Localization of visceral pain and other sensations before and after anesthesia

The localization of sensations in sense organs that developed ontogenetically from the ectoderm layer, like vision, hearing, and skin, is much more precise than sensations inside the body, like pain in the chest or viscera, which are produced by receptors developed from the entoderm layer. Pain on the surface of the skin is much more sharply localized than is pain in the viscera. Personal experiences of pain sensations produced by an obstruction in the colon and the effects of anesthesia are described. It became evident that anesthesia can influence the activity of the vestibular organ for many days.     

Apparent image rotation in stereoscopic vision: The unbalance of the pupils

In binocular vision the apparent rotation of an object relative to the frontal plane seldom corresponds with the actual rotation. The reason for this is a difference in the brightness of the object in both eyes. It can be produced by a difference in the pupil size, adaptation, or sensitivity. One of the purposes of the pupils seems to be to compensate for this brightness unbalance and to make the apparent rotation come closer to the actual one. Unbalance was produced by placing a density filter before one eye, and the corresponding rotations were then measured. The rotations are affected by the irradiation in the eye, as a physical component, but also by the lateral inhibition in the visual nervous system. If the object and the background have a different color but there is no brightness difference on the edges of the object, there is no distorted rotation.     

Levels and change in autonomous and controlled work motivation in older workers—The role of proximity to retirement and sense of community at work

Previous studies suggest a preretirement disengagement process from work, which includes reduced work motivation. In this study, we investigated changes in autonomous and controlled work motivation over two years among participants of the Health, Aging and Retirement Transition in Sweden (HEARTS) study. We found stability in both types of motivation; however, those who retired after the study period showed more distinct declines in autonomous motivation. A stronger sense of community at work was related to level, but not change in autonomous motivation. Intra-individual fluctuations in the expected retirement age did not predict work motivation or vice versa. Future studies are needed to better understand the antecedents and consequences of preretirement declines in autonomous work motivation.     

Watching diagnoses develop: Eye movements reveal symptom processing during diagnostic reasoning

Finding a probable explanation for observed symptoms is a highly complex task that draws on information retrieval from memory. Recent research suggests that observed symptoms are interpreted in a way that maximizes coherence for a single likely explanation. This becomes particularly clear if symptom sequences support more than one explanation. However, there are no existing process data available that allow coherence maximization to be traced in ambiguous diagnostic situations, where critical information has to be retrieved from memory. In this experiment, we applied memory indexing, an eye-tracking method that affords rich time-course information concerning memory-based cognitive processing during higher order thinking, to reveal symptom processing and the preferred interpretation of symptom sequences. Participants first learned information about causes and symptoms presented in spatial frames. Gaze allocation to emptied spatial frames during symptom processing and during the diagnostic response reflected the subjective status of hypotheses held in memory and the preferred interpretation of ambiguous symptoms. Memory indexing traced how the diagnostic decision developed and revealed instances of hypothesis change and biases in symptom processing. Memory indexing thus provided direct online evidence for coherence maximization in processing ambiguous information.