Attentional inhibition determines emotional responses to unfamiliar faces

Complex abstract images that are ignored in a simple localization task are subsequently judged more negatively in an emotional evaluation task than previously unseen or attended images, suggesting that attentional inhibition may have affective consequences (Raymond, Fenske, & Tavassoli, in press). We examined the generality of this finding by asking whether inhibitory processes might also influence the generation of emotional responses to unfamiliar faces. To do this, we incorporated an emotional evaluation task within a paradigm that has been used to demonstrate long-term inhibition-of-return (IOR) of attention (Tipper, Grison, & Kessler, in press). On each 2-task trial, observers were first shown a unique pair of unfamiliar faces while performing a speeded go/no-go task. In this task, observers were required to withhold a response if there was an abrupt onset of an exogenous cue (no-go trials), and to make a response if a different stimulus was presented (go ‘catch’ trials). Following the completion of an intervening task, observers where asked to make an affective evaluation about the faces they had previously seen in the go/no-go task (e.g., Which of these people looks more friendly?). We found that observers were less likely to make positive affective responses to faces that attention had been exogenously drawn to in no-go trials than to faces to which attention had never been exogenously allocated. These results converge with our previous finding to suggest that inhibition may be associated with an episode encoded into memory, and that later retrieval acts to reinstate inhibitory processing. Importantly, our results suggest that this inhibitory processing involves affective devaluation, which may serve to encourage examination of new information.

Three-factor models versus time series models:quantifying time-dependencies of interactions between stimuli in cell biology and psychobiology for short longitudinal data

Signal integration determines cell fate on the cellular level, affects cognitive processes and affective responses on the behavioural level, and is likely to be involved in psychoneurobiological processes underlying mood disorders. Interactions between stimuli may subjected to time effects. Time-dependencies of interactions between stimuli typically lead to complex cell responses and complex responses on the behavioural level. We show that both three-factor models and time series models can be used to uncover such time-dependencies. However, we argue that for short longitudinal data the three factor modelling approach is more suitable. In order to illustrate both approaches, we re-analysed previously published short longitudinal data sets. We found that in human embryonic kidney 293 cells cells the interaction effect in the regulation of extracellular signal-regulated kinase (ERK) 1 signalling activation by insulin and epidermal growth factor is subjected to a time effect and dramatically decays at peak values of ERK activation. In contrast, we found that the interaction effect induced by hypoxia and tumour necrosis factor-alpha for the transcriptional activity of the human cyclo-oxygenase-2 promoter in HEK293 cells is time invariant at least in the first 12-h time window after stimulation. Furthermore, we applied the three-factor model to previously reported animal studies. In these studies, memory storage was found to be subjected to an interaction effect of the beta-adrenoceptor agonist clenbuterol and certain antagonists acting on the alpha-1-adrenoceptor / glucocorticoid-receptor system. Our model-based analysis suggests that only if the antagonist drug is administer in a critical time window, then the interaction effect is relevant.

Primary and secondary somatosensory cortex responses to anticipation and pain: a magnetoencephalography study

Several brain regions, including the primary and secondary somatosensory cortices (SI and SII, respectively), are functionally active during the pain experience. Both of these regions are thought to be involved in the sensory-discriminative processing of pain and recent evidence suggests that SI in particular may also be involved in more affective processing. In this study we used MEG to investigate the hypothesis that frequency-specific oscillatory activity may be differentially associated with the sensory and affective components of pain. In eight healthy participants (four male), MEG was recorded during a visceral pain experiment comprising baseline, anticipation, pain and post-pain phases. Pain was delivered via intraluminal oesophageal balloon distension (four stimuli at 1 Hz). Significant bilateral but asymmetrical changes in neural activity occurred in the beta-band within SI and SII. In SI, a continuous increase in neural activity occurred during the anticipation phase (20-30 Hz), which continued during the pain phase but at a lower frequency (10-15 Hz). In SII, oscillatory changes only occurred during the pain phase, predominantly in the 20-30 Hz beta band, and were coincident with the stimulus. These data provide novel evidence of functional diversity within SI, indicating a role in attentional and sensory aspects of pain processing. In SII, oscillatory changes were predominantly stimulus-related, indicating a role in encoding the characteristics of the stimulus. We therefore provide objective evidence of functional heterogeneity within SI and functional segregation between SI and SII, and suggest that the temporal and frequency dynamics within cortical regions may offer valuable insights into pain processing.