News from the field. in the attention or weight given to particular multisensory cues. L.C.N. Emotion perception. The face and voice of emotion

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1 Atten Percept Psychophys (2011) 73:2 6 DOI /s News from the field # Psychonomic Society, Inc Emotion perception The face and voice of emotion Tanaka et al. (2010). I feel your voice: Cultural differences in the multisensory perception of emotion. Psychol Sci, 21, We display our emotions in a variety of ways, with both our faces and voices betraying the way we feel. As a consequence, when we attempt to gauge one another's emotional state, we must integrate information about emotion across multiple modalities, including cues from facial and vocal expressions of emotion. Tanaka et al. investigated whether this integration of multisensory emotional cues differs across culture. Japanese and Dutch participants were asked to judge emotion from audiovisual displays in which facial and vocal emotion was either congruent or incongruent. In one condition, participants judged whether faces were happy or angry while ignoring emotional tone of voice. In a second condition, participants judged happy or angry emotion from voice while ignoring facial expressions. The results showed that Japanese and Dutch participants differed in the way in which emotional cues were combined. Japanese participants appeared to weight vocal cues to emotion more strongly than the Dutch participants did. When judging facial expressions of emotion, Japanese participants paid more attention to vocal cues to emotion than Dutch participants did. When judging vocal expressions of emotion, Japanese participants were able to ignore conflicting facial cues while Dutch participants' judgments were influenced by to-be-ignored facial emotion. These findings suggest that cultural differences influence the perceptual combination of facial and vocal expressions of emotion. Differences in the degree to which emotion is displayed across cultures could result in differences in the attention or weight given to particular multisensory cues. L.C.N. Pre-conscious processes Things seen are temporal Falconbridge, Ware & MacLeod (2010). Imperceptibly rapid contrast modulations processed in cortex: Evidence from psychophysics. Journal of Vision. doi: / Just like Scalosians on the Enterprise or electrons in a cloud chamber, 80-Hz flicker may be too fast to see, but its effects are not. Prior to this new study, we knew that flicker frequencies in excess of 60 Hz were simply not noticeable. On the other hand, we also knew there were cortical neurons whose firing phase-locked with higher-frequency videos. Falconbridge and colleagues have succeeded in revealing one perceptual consequence of this consequently preconscious activity: orientation-selective contrast adaptation. Specifically, they found that the visibility of a phasereversing luminance grating falls more rapidly with temporal frequency than the ratio of its effects on the visibilities of subsequently flashed, parallel, and perpendicular gratings. One further datum from Falconbridge et. al. banishes all skepticism regarding the role of consciousness in orientation-selective adaptation. Observers were asked to discriminate between perpendicular, masked adaptors. Subsequently viewed gratings that were parallel to the adaptor appeared to have less contrast than otherwise identical gratings that were perpendicular, regardless whether observers identified the adaptor correctly or not. So, essentially, our visual system can adapt to something flickering too fast to see. Conversely,

2 Atten Percept Psychophys (2011) 73:2 6 3 Motoyoshi & Hayakawa [J Vis, 10(2), Art. 16] have shown that adapting to flicker can make subsequently viewed gratings invisible. Could adaptation to an invisible gratingmakeusblindtosubsequentlypresentedgratings? It remains to be seen (or not). J.A.S. Global form perception Colorful glass patterns Rentzeperis, I & Kiper DC (2010) Evidence for color and luminance invariance of global form mechanisms. Journal of Vision 10(12):6, 1 14, content/10/12/6, doi: / Glass, L (1969). Moire effect from random dots. Nature, 223, Glass patterns have fascinated vision scientists since they were first described (Glass, 1969). A rotational Glass pattern is generated by starting with a circular patch of random dots, then rotating that patch around its center through some small angle and adding the rotated patch to the original patch. When people view the resulting image, they easily perceive the global, concentric structure produced by the correlations of the rotated with the original dots. An expansive Glass pattern is generated similarly, except instead of rotating the original patch, one expands it out from the center by some small amount before adding it to the original image. In this case, again, people easily perceive the global radial structure in the combined image. But how do different types of low-level visual information combine to produce the global structureseeninglasspatterns?thiswasthequestion asked by Rentzeperis & Kiper (2010). Substantial evidence suggests that human vision analyzes the retinal signal into three channels, a black-white channel, a redgreen channel, and a blue-yellow channel. Rentzeperis & Kiper used Glass patterns carefully calibrated so that their dots would activate only a single one of these channels. For example, in one condition they used pinkish dots visible to the red-green channel but not to either the white-black or blue-yellow channels. They then asked how adaptation to a given single-channel Glass pattern would influence sensitivity to the global structure of other single-channel Glass patterns. The results were clear: adaptation to any single-channel Glass pattern (either rotational or expansive) decreased sensitivity to the global structure of any similarly structured Glass pattern regardless of whether the channel of the test pattern was the same as or different from the channel of the adapting pattern. One might be tempted to conclude from this result that all dots are created equal (regardless of how they are defined) for the process that extracts global structure from a Glass pattern. This is not true, however. The local orientation signal produced by a pair of dots depends strongly on how the two dots are defined. As one might expect, a pair of white dots on a gray background activates neurons selective for orientation in the direction of the displacement between the dots; however, if one dot is black and the other is white, then the dot-pair activates neurons tuned to orientation contrary to the dot displacement. As this might suggest, a Glass pattern whose dots are reversed in contrast across the two combined frames evokes a very different percept of global structure than does an ordinary Glass pattern. Thus, Rentzeperis s & Kiper s finding suggests that although local orientation is extracted within the separate red-green, black-white, and blue-yellow channels, the outputs of these channels are pooled by the process that extracts global spatial structure. C.F.C. Reading Missing-letter effect and RSVP Saint-Aubin, J., Nenny, S. & Roy-Charland, A. (2010) The role of eye movements in the missing-letter effect revisited with the rapid serial visual presentation procedure. CJEP, 64, 47. In experiments where participants are asked to read a text displayed normally and search for a target letter, it is more likely that they will miss the target letter if this letter is part of frequent function words than if it is part of significant (and less frequent) words. Indeed, less frequent words are fixated on for a greater amount of time than are function words. When a rapid serial visual presentation (RSVP) procedure is used, i.e., one word presented at a time, the same pattern of omission is observed. This could be interpreted as it not being the fixation duration per se that causes the missing-letter effect. This would be true if it could be shown that there are no eye movements during the RSVP procedure. The experiment conducted by Saint-Aubin et al. is the first one investigating eye movements during a RSVP procedure. In addition to replicating typical findings like the fact that the missingletter effect is larger with faster presentation durations, the experiment shows that whether function (frequent) or content (less frequent) words are presented, the duration of fixation is the same, i.e., it lasts for the entire duration of the presentation (200, 350 or 500 ms). Consequently, it could be concluded that the missing-letter effect is not caused by eye movements. S.G.

3 4 Atten Percept Psychophys (2011) 73:2 6 Visual crowding Target-flanker separation: further is not necessarily better Saarela, T. P., Westheimer, G., & Herzog, M. H. (2010). The effect of spacing regularity on visual crowding. Journal of Vision, 10(10):17, 1 7. Our ability to identify a peripheral target considerably declines when it is flanked by other stimuli. This phenomenon is termed crowding, and many studies have shown that crowding decreases as the spacing between the target and its flankers increases. Many of the current accounts that were offered to explain the phenomenon of crowding were inspired by this effect of target-flanker separation. Interestingly, Saarela, Westheimer and Herzog are showing that the strength of crowding is not determined solely by target-flanker separation, and that under certain conditions larger separations do not entail better performance and may even result in worse performance. This was demonstrated using both Gabor patches and letters as stimuli. The target was presented with multiple flankers under several spacing conditions. In the tight condition the stimuli were regularly spaced, with inter-stimuli distance of 1º. In this condition the spacing between the target and its adjacent flankers was the smallest. The flankers array in the shifted condition was identical but the flankers adjacent to the target were shifted outward so that the spacing between them and the target was larger (1.25º). In the wide condition the flankers were also regularly spaced, but the inter-stimuli distance was 1.25º. Finally, in the added condition the spacing between the target and its adjacent flankers was also 1.25º but all other inter-stimuli distances were smaller as additional items were inserted between the regular spacing of the wider condition. Performance in these conditions was compared to a baseline condition with no flankers. Not surprisingly, crowding was stronger in the tight condition than the shifted condition, probably due to the larger spacing between the target and the adjacent flankers. Critically, although the average flanker-target distance was larger in the wide than shifted condition, while the spacing between the adjacent flankers and the target was identical in both conditions, the strength of crowding in the wide condition was not reduced and even increased in comparison to the shifted condition. Moreover, the crowding effect was larger in the wide than added condition even though there were more flankers in the added condition, and the spacing between the target and the adjacent flankers and the average distance between the target and the flankers were identical. In sum, Saarela et al. found that the average distance between the target and its flankers, the spacing between the target and its adjacent flankers, and the number of flankers are not good predictors of the strength of crowding. Instead, a decisive factor seems to be the manner by which the items are segmented into perceptual groups. In the two regular spacing conditions tight and wide the flankers and the target were organized into a single group, which resulted in strong crowding. In the other conditions, due to the non-regular spacing, the flankers on each side of the target were organized into separate groups and the target stood out as an individual element. This study, therefore, underscores the crucial role that perceptual organization plays in the crowding phenomenon. Y.Y. Emotion perception Does the amygdala have its own visual system? Pessoa, L., & Adolphs, R. (2010). Emotion processing and the amygdala: from a 'low road' to 'many roads' of evaluating biological significance. [doi: /nrn2920]. Nat Rev Neurosci, 11(11), Stimuli of emotional significance have received a lot of attention in recent years, in part, because a number of researchers have concluded that you can processes them without a lot of attention. That is, in order to read these words, you must direct your attention to the text, word after word. However, it has been argued, if a fearful face was present in your field of view, you could appreciate that fear without directing attention to the face and, indeed, as a result of that preattentive or non-attentive processing, the face might capture your attention. A subcortical pathway from retina to superior colliculus to pulvinar to amygdala has been proposed as a neural substrate for this processing of affective stimuli. The pathway is proposed to be very fast but relatively insensitive to high spatial frequencies in the manner of the magnocellular pathway from retina to visual cortex. This is what Pessoa and Adolphs call the standard hypothesis in their recent article in Nature Reviews Neuroscience. Their goal is to summarize the arguments against a fast, automatic, low spatial freq pathway to the amygdala that preferentially processes emotional stimuli and to propose an alternative. So, what are the problems with the standard view? First, appreciation of the emotional content of a stimulus, while it can be fast, is not uniquely fast. For instance, last year, Greene and Oliva published a paper in Psych Science showing that observers can make categorical judgments about scenes (e.g. natural vs. manmade) with as little as 20 msec of input. A second problem is that high spatial frequency information seems to contribute to assessment of the emotional content of

4 Atten Percept Psychophys (2011) 73:2 6 5 stimuli. Finally, lesion studies indicate that the amygdala is not necessary for detection of emotional stimuli whatever its role may be in the experience of emotion. Instead of a dedicated subcortical road for the processing of emotional stimuli, Pessoa and Adolphs argue for what they call a many roads approach in which the amygdala and pulvinar orchestrate the interplay between multiple cortical networks with a stake in the task. In some ways, this is a bit of a relief. Consider that fearful face. There is a lot of cortical visual system that seems to be devoted to a task like face perception. One of the difficulties of the hypothesis of a dedicated, subcortical path to the amygdala is that one would have to assume this pathway constituted a complete visual system of its own, perhaps coarser than the primary cortical system, but still capable of some very sophisticated visual analysis. The many roads account can make use of the cortex s talents, eliminating the need to duplicate functions. The Pessoa and Adolphs account is one where many roads seem more parsimonious than one. J.M.W. Attention control Can irrelevant symbols elicit involuntary shifts of attention? Leblanc, E., & Jolicoeur, P. (2010). How do selected arrows guide visuospatial attention? Dissociating symbolic value and spatial proximity. JEP:HPP, 36, Pratt, J., Radulescu, P., Guo, R. M., & Hommel, B. (2010). Visuospatial attention is guided by both symbolic value and the spatial proximity of selected arrows. JEP:HPP, 36, For the past twenty years, researchers have debated whether salient visual features can capture attention in a purely stimulus-driven fashion. More recently, researchers have also considered whether learned symbols such as arrows can also elicit involuntary shifts of attention. This question has been addressed within the context of the spatial cuing paradigm in which uninformative arrow cues are shown prior to a task-relevant target display. Because the cue is uninformative, the target only appears at the cued location by chance; and, for this reason, observers are typically instructed to ignore the cue. Nevertheless, evidence has accumulated to suggest that attention does in fact appear to be shifted to the locations indicated by the uninformative arrow cues, though debate continues over whether these shifts of attention should be construed as being purely involuntary. Several years ago, Pratt and Hommel (2003; JEP:HPP, 29, ) contributed to this literature by considering how attention might be allocated when several, potentially competing, symbols were present in the visual field. They suggested that such competition may be resolved by a biased competition mechanism that favors those symbols that happen to be congruent with other task goals. For instance, in their paradigm, four arrows pointed outward from fixation along the four cardinal directions. Furthermore, each of the arrows appeared in a unique color; and, the color of one of the arrows always matched the color of the target dot, which was cued at the beginning of each trial. Observers were instructed to press a response key as quickly and accurately as possible when the target dot appeared, but they were instructed to withhold their response when a dot of a non-cued color appeared. Critically, the target dot appeared at the same location that color-congruent arrow was pointing only by chance. Pratt and Hommel hypothesized that maintenance of the target color would cause observers to select and process the colorcongruent arrow, which in turn, would cause attention to be involuntarily shifted to the specified location. Consistent with this expectation, Pratt and Hommel found that detection RTs were faster when the target dot happened to appear at the color-congruent cued location relative to when it appeared at one of the alternative, color-incongruent, cued locations. Leblanc and Jolicoeur took issue with the interpretation of this finding by pointing out that the location that was symbolically cued by the color-congruent arrow was also the location that was most proximal to this cue. Thus, they argued that the observed cuing effect could reflect a spatial proximity effect rather than a symbolic cuing effect. To investigate this possibility, they attempted to de-confound symbolic cuing from spatial proximity by presenting cues that were close to one location while pointing to a more distal location. Their findings suggested that spatial proximity was the critical factor; in other words, targets were detected faster when they appeared near to the colorcongruent arrow cue relative to when they appeared further away, but targets were detected equally fast regardless of whether they appeared at the symbolically-cued spatial location or not. These findings are potentially important because they are inconsistent with the notion that uninformative symbolic cues can elicit involuntary shifts of attention based on the spatial information that is conveyed indirectly via the symbol. In response to Leblanc and Jolicoeur s criticism, Pratt and colleagues conceded that spatial proximity may in fact lead to a spatial cuing effect; however, they attributed the null effect of symbolic cuing to an inability of these cues to guide attention across the horizontal or vertical visual meridian. To address this issue, Pratt and colleagues designed an experiment in which spatial proximity could be dissociated from symbolic cuing, but without requiring that attention be shifted across a visual meridian in response

5 6 Atten Percept Psychophys (2011) 73:2 6 to these cues. This was accomplished by presenting two cues on any given trial one that was congruent with the target s color and one that was inconsistent. In addition, the cues could appear either far or near to the target s location. Most importantly, Pratt and colleagues compared two types of cues: directional arrow cues and non-directional circle cues. If spatial proximity is critical, then targets should be detected faster when they appear near to color-congruent cues relative to when they appear far from color-congruent cues (regardless of whether directional or non-directional cues are shown). In contrast, if directional information is critical, then targets should be detected faster when they appear at the color-congruent location relative to the colorincongruent location. Consistent with Leblanc and Jolicoeur s findings, Pratt et al. found that targets were detected faster when they appeared near the color-congruent cues than when they appeared far from the color-congruent cues. However, inconsistent with Leblanc and Jolicoeur s findings, Pratt et al. also found that targets were detected faster when they appeared at the color-congruent location than when they appeared at the color-incongruent location. Thus, these findings are important because they suggest that spatial proximity and spatial semantics both appear capable of eliciting involuntary shifts of attention. B.S.G. Conflict monitoring Reward-based learning affects stroop interference Krebs et al. (2010). The influence of reward associations on conflict processing in the Stroop task. Cognition, 117, 341. The Stroop task has been widely used to investigate both automaticity and cognitive control under conflict situations. The task has been used to investigate the brain mechanisms of conflict resolution in various patient populations and in neuroimaging studies, with one main finding suggesting that frontal lobe regions, including the anterior cingulate cortex, are involved in conflict resolution. Against this backdrop, many recent reviews have suggested that the neural regions involved in conflict control might also be involved in learning based on feedback (i.e., reward and punishment). This connection between conflict and reward led Krebs et al. to ask if Stroop conflict could be modulated by reward-based learning. Participants performed a standard Stroop color naming task, in which they read the ink color of printed words. Two of the ink colors were associated with the potential for a monetary reward (the potential reward condition); two other ink colors were not associated with the possibility of a reward (the no reward condition). In the potential reward condition, participants received extra payment for responses that were correct and were below a response deadline; slow or inaccurate responses were not rewarded in this condition. No rewards were given in the no reward condition. Importantly, the color words appeared equally in the potential reward and no reward conditions. For example, if the colors green and blue were chosen for the potential reward condition, the words blue and green appeared equally in both conditions (as did the other color words, red, yellow, and brown ). The results demonstrated differences between the two reward conditions. Overall, responses were faster in the potential reward condition than in the no reward condition. The potential for reward did not produce a speed-accuracy tradeoff, however. Not only were response times faster in the potential reward condition than in the no reward condition, accuracy was also higher in the former than in the latter. A more detailed comparison between the incompatible and neutral trials suggested less interference on potential reward trials than on no reward trials. In a second experiment, Krebs and colleagues replicated their main findings but also examined extinction of the learning effects. Following presentation of potentially rewarding and non rewarding trials, participants then performed a standard Stroop task in which none of the ink colors were rewarded. Extinction trials continued to show faster response times for ink colors that had been potentially rewarded than those that were not rewarded, and the same held for a separate analysis of the incompatible trials alone. The potential for reward clearly affected Stroop performance, tightening cognitive control by excluding information on the irrelevant (word) dimension. Following the cognitive neuroscience literature on cognitive control, Krebs et al. suggest that dopaminergic pathways might be involved in their findings, because dopamine has been implicated in both conflict monitoring and reward. Irrespective of the neural underpinnings, their results suggest an interesting new dimension to attentional control more generally. S.P.V.