Natural-scene perception requires attention

Is visual attention required for visual consciousness? In the past decade, many researchers have claimed that awareness can arise in the absence of attention. This claim is largely based on the notion that natural scene (or "gist") perception occurs without attention. This article presents evidence against this idea. We show that when observers perform a variety of demanding, sustained-attention tasks, inattentional blindness occurs for natural scenes. In addition, scene perception is impaired under dual-task conditions, but only when the primary task is sufficiently demanding. This finding suggests that previous studies that have been interpreted as demonstrating scene perception without attention failed to fully engage attention and that natural-scene perception does indeed require attention. Thus, natural-scene perception is not a preattentive process and cannot be used to support the idea of awareness without attention.     

Homicide as conflict resolution

Homicide research at societal, subcultural, and interaction levels of analysis has not produced a comprehensive model for the killer‐victim transaction. But rules for organizing the experience of homicide can be generated from Simmel's definition of conflict as a “resolution of divergent dualisms” (1955:11). A model of homicide as a form of conflict resolution is demonstrated through interviews with a random sample of 35 adjudicated killers. Respondents’ definitions of homicide correspond to the conflict resolution model, with their verbal accounts, their socio‐psychological orientation to the victim at the point of the killing, their method of killing, and the general dynamics of the killer‐victim transaction, all varying as a resolution of a distinctive relationship, either between lovers, adversaries, or strangers. The situational definition casts homicide within the realm of normal behavior and at the same time delineates its distinctive features.     

Homicide and suicide: Structure and process

This article brings together major new findings on homicide and suicide in order to contribute to an awareness of the similarities and differences between the two at both the structural and process levels of analysis, to make causal inferences, and to stimulate future research. Both homicide and suicide are processes of fixation on conflict resolution. The process of conflict resolution in turn is conditioned by structural disorganization. The process of fixation is conditioned by structural segregation, taking the particular form of estrangement, self‐reliance, and partial isolation. Intentional suicide, as distinct from intentional homicide, involves a negative fixation on self resulting primarily from the physical or psychological unavailability of a victim. The lack of a victim leaves the would‐be suicide feeling overwhelmed by the emotion that he or she fears. This process is conditioned by age and societal centralization, which together deny opportunities for homicide and detract from the kind of social support that might make life seem worthwhile.     

Recognition of notated melodies by possessors and nonpossessors of absolute pitch

Musically trained listeners compared a notated melody presented visually and a comparison melody presented auditorily, and judged whether they were exactly the same or not, with respect to relative pitch. Listeners who had absolute pitch showed the poorest performance for melodies transposed to different pitch levels from the notated melodies, whereas they exhibited the highest performance for untransposed melodies. By comparison, the performance of melody recognition by listeners who did not have absolute pitch was not influenced by the actual pitch level at which melodies were played. These results suggest that absolute-pitch listeners tend to rely on absolute pitch even in recognizing transposed melodies, for which the absolute-pitch strategy is not useful.     

Investigating the acute effect of an aerobic dance exercise program on neuro-cognitive function in the elderly

ObjectiveThe present study investigated the types of aerobic dance programs that positively impact cognition, such as executive function, in elderly people.DesignRandomized controlled trial.MethodThe study compared the effects of acute aerobic dance exercise on cognitive performance using two 40-min aerobic dance programs. Thirty-four elderly participants, aged 65–75 years, were randomly assigned into either free (N = 17) or combination (N = 17) style workout groups. The free style (FR) workout consisted of several patterns of movement, while the combination style (CB) workout consisted of similar patterns of movement to FR, but the patterns were joined to form a long choreographic routine. Both dance programs were controlled to be the same in exercise intensity, approximately 40% heart rate reserve. Reaction time and correct rates were measured using a task-switching reaction time test to evaluate executive cognitive performance immediately before and after the 40-min dance exercise.ResultsA two-way (dance program × pre-post dance exercise) repeated-measures analysis of variance for switch reaction time increase (switch cost) demonstrated a significant interaction (p = .006), showing that the switch cost in the CB group became smaller after the dance exercise than before (p = .009).ConclusionThe results suggest that the executive cognitive network was facilitated in a CB dance workout that has a dual-task nature and induces movement (task) interference with unexpected movement changes.     

Whither geometry? Troubles of the geometric module

In rectangular arenas, rats often confuse diagonally opposite corners, even when distinctive cues differentiate them. This led to the postulation that rats rely preferentially on the geometry of space, encoded in a dedicated geometric module. Recent research casts doubt on this idea. Distinctive featural cues such as entire walls of a distinct color can hinder or aid the learning of geometry. In one situation in which using geometry would help greatly, rats had trouble learning the task. An associative model has been developed to capture these different learning processes, and view-based matching has been proposed as an alternative to the explicit coding of geometric cues. Considerations about how cues interact in learning are crucial in a recent theory of human spatial cognition.     

The information content of panoramic images II: view-based navigation in nonrectangular experimental arenas

Two recent studies testing navigation of rats in swimming pools have posed problems for any account of the use of purely geometric properties of space in navigation (M. Graham, M. A. Good, A. McGregor, & J. M. Pearce, 2006; J. M. Pearce, M. A. Good, P. M. Jones, & A. McGregor, 2004). The authors simulated 1 experiment from each study in a virtual reality environment to test whether experimental results could be explained by view-based navigation. The authors recorded a reference image at the target location and then determined global panoramic image differences between this image and images taken at regularly spaced locations throughout the arena. A formal model, in which an agent attempts to minimize image differences between the reference image and current views, generated trajectories that could be compared with the search performance of rats. For both experiments, this model mimics many aspects of rat behavior. View-based navigation provides a sufficient and parsimonious explanation for a range of navigational behaviors of rats under these experimental conditions.