The present study evaluated and compared the psychometric properties of three self-report scales: the Snaith-Hamilton Pleasure Scale (SHAPS; R. P. Snaith, M. Hamilton, S. Morley, & A. Humayan, 1995), Fawcett-Clark Pleasure Capacity Scale (FCPS; J. Fawcett, D. C. Clark, W. A. Scheftner, & R. D. Gibbons, 1983), and the Revised Chapman Physical Anhedonia Scale (CPAS; L. J. Chapman, J. P. Chapman, & M. L. Raulin, 1976). These scales, designed to assess hedonic responsiveness, were administered to 157 college students. Confirmatory factor analysis revealed a Hedonic Capacity factor that was largely defined by the SHAPS but also had a substantial loading from the FCPS. Hedonic Capacity was minimally correlated with constructs of Depression and Anxiety, which were assessed by the Beck Depression Inventory-II and the Beck Anxiety Inventory. The CPAS (anhedonia) was not significantly related to Hedonic Capacity or Anxiety, but it did have a small positive loading on Depression. These findings suggest that further research is needed to clarify the meaning of and relationships among scales that are putative indicators of hedonic capacity and anhedonia.

Both perceptual load theory and dilution theory purport to explain when and why task-irrelevant information, or so-called distractors are processed. Central to both explanations is the notion of limited resources, although the theories differ in the precise way in which those limitations affect distractor processing. We have recently proposed a neurally plausible explanation of limited resources in which neural competition among stimuli hinders their representation in the brain. This view of limited capacity can also explain distractor processing, whereby the competitive interactions and bias imposed to resolve the competition determine the extent to which a distractor is processed. This idea is compatible with aspects of both perceptual load and dilution models of distractor processing, but also serves to highlight their differences. Here we review the evidence in favor of a biased competition view of limited resources and relate these ideas to both classic perceptual load theory and dilution theory.

Prior research on visual priming suggests that during nonconscious processing attention can be directed to single stimulus dimensions such as form or color. In the current experiment, nonconscious priming was compared to conscious priming by employing masking techniques that render primes invisible (masked) or visible (unmasked) to the observers. Observers were asked to respond to the form, the color, or the combination of form and color of the mask-probe that followed either a masked or an unmasked prime. The prime varied in its form and color congruency relative to the mask-probe. The results indicate (1) that during nonconscious processing a task-irrelevant stimulus feature can be attentionally filtered out, (2) that during nonconscious processing only separated stimulus features can be attended, and (3) that during conscious processing the conjunction of stimulus features comprising an object can be attended. Furthermore, the results indicate that at the nonconscious level stimuli are processed at an individual-feature level, while at the conscious level the stimuli can additionally be processed at a whole-object level.

A number of influential theories posit that visual awareness relies not only on the initial, stimulus-driven (i.e., feedforward) sweep of activation but also on recurrent feedback activity within and between brain regions. These theories of awareness draw heavily on data from masking paradigms in which visibility of one stimulus is reduced due to the presence of another stimulus. More recently transcranial magnetic stimulation (TMS) has been used to study the temporal dynamics of visual awareness. TMS over occipital cortex affects performance on visual tasks at distinct time points and in a manner that is comparable to visual masking. We draw parallels between these two methods and examine evidence for the neural mechanisms by which visual masking and TMS suppress stimulus visibility. Specifically, both methods have been proposed to affect feedforward as well as feedback signals when applied at distinct time windows relative to stimulus onset and as a result modify visual awareness. Most recent empirical evidence, moreover, suggests that while visual masking and TMS impact stimulus visibility comparably, the processes these methods affect may not be as similar as previously thought. In addition to reviewing both masking and TMS studies that examine feedforward and feedback processes in vision, we raise questions to guide future studies and further probe the necessary conditions for visual awareness.

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