Eye scanpaths during visual imagery reenact those of perception of the same visual scene

Eye movements during mental imagery are not epiphenomenal but assist the process of image generation. Commands to the eyes for each fixation are stored along with the visual representation and are used as spatial index in a motor‐based coordinate system for the proper arrangement of parts of an image. In two experiments, subjects viewed an irregular checkerboard or color pictures of fish and were subsequently asked to form mental images of these stimuli while keeping their eyes open. During the perceptual phase, a group of subjects was requested to maintain fixation onto the screen's center, whereas another group was free to inspect the stimuli. During the imagery phase, all of these subjects were free to move their eyes. A third group of subjects (in Experiment 2) was free to explore the pattern but was requested to maintain central fixation during imagery. For subjects free to explore the pattern, the percentage of time spent fixating a specific location during perception was highly correlated with the time spent on the same (empty) locations during imagery. The order of scanning of these locations during imagery was correlated to the original order during perception. The strength of relatedness of these scanpaths and the vividness of each image predicted performance accuracy. Subjects who fixed their gaze centrally during perception did the same spontaneously during imagery. Subjects free to explore during perception, but maintaining central fixation during imagery, showed decreased ability to recall the pattern. We conclude that the eye scanpaths during visual imagery reenact those of perception of the same visual scene and that they play a functional role.     

A Systematic Review and Quality Assessment of Therapeutic Group Process Questionnaires

ABSTRACT

The aims of this study were to systematically review the literature on questionnaire-based group process measures and assess the psychometric scale development properties of these measures. A systematic search of questionnaire-based measures of group process was conducted from four databases: PsycINFO, Medline, EMBASE and AMED. A quality assessment was undertaken using established criteria. Only studies that described the development of questionnaire-based scales were included. Seventeen studies which described thirteen measures were included in the analysis. The developed list highlights a range of questionnaires that can be used by clinicians and researchers seeking to measure either “specific therapeutic group mechanisms” or “overall group experiences.” Further research should focus on developing the content validity of these scales by involving the target population during item selection and reduction.