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No / Which is better, a visual or an auditory warning signal? Initial findings suggested that an auditory signal was more effective, speeding reaction to a target more than a visual warning signal, particularly at brief foreperiods [Bertelson, P., & Tisseyre, F. (1969). The time-course of preparation: confirmatory results with visual and auditory warning signals. Acta Psychologica, 30. In W.G. Koster (Ed.), Attention and Performance II (pp. 145-154); Davis, R., & Green, F. A. (1969). Intersensory differences in the effect of warning signals on reaction time. Acta Psychologica, 30. In W.G. Koster (Ed.), Attention and Performance II (pp. 155-167)]. This led to the hypothesis that an auditory signal is more alerting than a visual warning signal [Sanders, A. F. (1975). The foreperiod effect revisited. Quarterly Journal of Experimental Psychology, 27, 591-598; Posner, M. I., Nissen. M. J., & Klein, R. M. (1976). Visual dominance: an information-processing account of its origins and significance. Psychological Review, 83, 157-171]. Recently [Turatto, M., Benso, F., Galfano, G., & Umilta, C. (2002). Nonspatial attentional shifts between audition and vision. Journal of Experimental Psychology; Human Perception and Performance, 28, 628-639] found no evidence for an auditory warning signal advantage and showed that at brief foreperiods a signal in the same modality as the target facilitated responding more than a signal in a different modality. They accounted for this result in terms of the modality shift effect, with the signal exogenously recruiting attention to its modality, and thereby facilitating responding to targets arriving in the modality to which attention had been recruited. The present study conducted six experiments to understand the cause of these conflicting findings. The results suggest that an auditory warning signal is not more effective than a visual warning signal. Previous reports of an auditory superiority appear to have been caused by using different locations for the visual warning signal and visual target, resulting in the target arriving at an unattended location when the foreperiod was brief. Turatto et al.'s results were replicated with a modality shift effect at brief foreperiods. However, it is also suggested that previous measures of the modality shift effect may still have been confounded by a location cuing effect.

Creativity can be a useful skill in today's classrooms and workplaces. When individuals talk about creativity, it's unclear what the controlling variables are when we tact behavior as "creative." Research in understanding the processes behind behaviors that are considered "creative" would assist in identifying functional relations and provide insight on how to teach creativity. Since creativity is often described as doing something different from the norm, behavioral variability may be a potential aspect of creativity. This study aimed to replicate previous findings by investigating the effects of discrimination training in a multiple schedule of varied and repetitive responding in the context of a video game. Participants played through a 2D online video game made in Bloxels. Different alternating-colored platforms served as the discriminative stimuli for the vary and repeat components. Three parameters of variability were measured (e.g., left jumps, right jumps, and double jumps). The results of the study indicate that participants were able to learn the discrimination of when to repeat and vary their responses depending on which colored platform they encountered.

Yes / This paper builds a framework to jointly examine the possibility of both `expansionary fiscal contractions' (austerity increasing output) and `fiscal free lunches' (expansions reducing government debt), arguments supported by the austerity and stimulus camps, respectively, in recent debates. We propose a new metric quantifying the budgetary implications of fiscal action, a key aspect of fiscal policy particularly at the monetary zero lower bound. We find that austerity needs to be highly persistent and credible to be expansionary, and stimulus temporary, responsive and well-targeted in order to lower debt. We conclude that neither are likely, especially during periods of economic distress.

No / Vernier acuity depends on the integration of information from multiple photoreceptors. For this reason, vernier acuity thresholds ought to exhibit effects of stimulus size and contrast analogous to those that occur in area summation experiments. In this paper, we consider some area and contrast effects found in vernier acuity experiments, and explain them with a model of detection and discrimination which we call the Noisy Template model. The Noisy Template model assumes that psychophysical tasks are performed (or can be approximated) by cross-correlation of the stimulus with a decision template which is optimal for the task at hand. The Noisy Template model crucially adds the assumption that the template contains noise. This yields inefficiency in the decision process which increases with stimulus size and contrast. Predictions of the Noisy Template model are derived for the case of vernier acuity, and compared with existing experiments.

No / A current, popular, theory of spatial localization holds that the visual system represents the location of simple objects by a single positional tag, the accuracy of which is largely independent of the internal properties of the object. We have already presented evidence of the limitations of such a view (Keeble & Hess (1998). Vision Research, 38, 827-840) in that 3-micropattern alignment performance was found to be dependent on the orientation of the micropatterns. We tested whether this was caused by a local anisotropy in positional coding by conducting 3-micropattern bisection experiments with varying patch orientation. No corresponding effect of patch orientation was found, implying a difference in the mechanisms used for the two tasks. In a further experiment we show that alignment task performance is very similar to the otherwise identical 2-patch orientation discrimination task. We conclude that the 3-micropattern alignment task is mediated by orientational mechanisms. We therefore present a 2nd-order orientation model for 3-patch alignment.

Yes / Where do the bottlenecks for information and attention lie when our visual system processes incoming stimuli? The human visual system encodes the incoming stimulus and transfers its contents into three major memory systems with increasing time scales, viz., sensory (or iconic) memory, visual short-term memory (VSTM), and long-term memory (LTM). It is commonly believed that the major bottleneck of information processing resides in VSTM. In contrast to this view, we show major bottlenecks for motion processing prior to VSTM. In the first experiment, we examined bottlenecks at the stimulus encoding stage through a partial-report technique by delivering the cue immediately at the end of the stimulus presentation. In the second experiment, we varied the cue delay to investigate sensory memory and VSTM. Performance decayed exponentially as a function of cue delay and we used the time-constant of the exponential-decay to demarcate sensory memory from VSTM. We then decomposed performance in terms of quality and quantity measures to analyze bottlenecks along these dimensions. In terms of the quality of information, two thirds to three quarters of the motion-processing bottleneck occurs in stimulus encoding rather than memory stages. In terms of the quantity of information, the motion-processing bottleneck is distributed, with the stimulus-encoding stage accounting for one third of the bottleneck. The bottleneck for the stimulus-encoding stage is dominated by the selection compared to the filtering function of attention. We also found that the filtering function of attention is operating mainly at the sensory memory stage in a specific manner, i.e., influencing only quantity and sparing quality. These results provide a novel and more complete understanding of information processing and storage bottlenecks for motion processing. / Supported by R01 EY018165 and P30 EY007551 from the National Institutes of Health (NIH).