Edward Bernat | PubMed Health

PubMed2006

Effects of picture content and intensity on affective physiological response.

This study evaluated the effects of affective intensity and thematic content of foreground photographic stimuli on various physiological response systems. This was accomplished by assessing responses to pictures that varied systematically in these parameters. Along with overall effects of picture valence reported in previous work, we found effects of thematic content (i.e., specific nature of objects/events depicted) for all measures except heart rate. In addition, we found that the magnitude of startle blink, skin conductance, and corrugator muscle reactions increased with increasing affective intensity of pictures. Additionally, for these three measures, intensity effects also interacted with effects of picture content. These results indicate that stimulus parameters of intensity and thematic content exert separate-and in some cases interactive-modulatory effects on physiological reactions to emotional pictures.

Adult↗

PubMed2004

Unconscious perception: a model-based approach to method and evidence.

Unconscious perceptual effects remain controversial because it is hard to rule out alternative conscious perception explanations for them. We present a novel methodological framework, stressing the centrality of specifying the single-process conscious perception model (i.e., the null hypothesis). Various considerations, including those of SDT (Macmillan & Creelman, 1991), suggest that conscious perception functions hierarchically, in such a way that higher level effects (e.g., semantic priming) should not be possible without lower level discrimination (i.e., detection and identification). Relatedly, alternative conscious perception accounts (as well as the exhaustiveness, null sensitivity, and exclusiveness problems-Reingold & Merikle, 1988, 1990) predict positive relationships between direct and indirect measures. Contrariwise, our review suggests that negative and/or nonmonotonic relationships are found, providing strong evidence for unconscious perception and further suggesting that conscious and unconscious perceptual influences are functionally exclusive (cf. Jones, 1987), in such a way that the former typically override the latter when both are present. Consequently, unconscious perceptual effects manifest reliably only when conscious perception is completely absent, which occurs at the objective detection (but not identification) threshold.

Humans↗