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Emotional faces are often salient cues of threats or other important contexts, and may therefore have a large effect on cognitive processes of the visual environment. Indeed, many behavioral studies have demonstrated that emotional information can modulate visual attention and eye movements. The aim of the present study was to investigate (1) how irrelevant emotional face distractors affect saccadic behaviors and (2) whether such emotional effects reflect a specific neural mechanism or merely biased selective attention. We combined a visual search paradigm that incorporated manipulation of different types of distractor (fearful faces or scrambled faces) and delivered anodal transcranial direct current stimulation (tDCS) over the superior temporal sulcus and the frontal eye field to investigate the functional roles of these areas in processing facial expressions and eye movements. Our behavioral data suggest that irrelevant emotional distractors can modulate saccadic behaviors. The tDCS results showed that while rFEF played a more general role in controlling saccadic behavior, rSTS is mainly involved in facial expression processing. Furthermore, rSTS played a critical role in processing facial expressions even when such expressions were not relevant to the task goal, implying that facial expressions and processing may be automatic irrespective of the task goal., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The interaction between goal-directed and stimulus-driven attentional control allows humans to rapidly reorient to relevant objects outside the focus of attention--a phenomenon termed contingent reorienting. Neuroimaging studies have observed activation of the ventral and dorsal attentional networks, but specific involvement of each network remains unclear. The present study aimed to determine whether both networks are critical to the processes of top-down contingent reorienting. To this end, we combined the contingent attentional capture paradigm with the use of transcranial magnetic stimulation (TMS) to interfere with temporoparietal junction (TPJ; ventral network) and frontal eye field (dorsal network) activity. The results showed that only right TPJ (rTPJ) TMS modulated contingent orienting. Furthermore, this modulation was highly dependent on visual fields: rTPJ TMS increased contingent capture in the left visual field and decreased the effect in the right visual field. These results demonstrate a critical involvement of the ventral network in attentional reorienting and reveal the spatial selectivity within such network., (Copyright © 2012 Wiley Periodicals, Inc.)

Many studies have used static and non-biologically related stimuli to investigate bistable perception and found that the percept is usually dominated by their intrinsic nature with some influence of voluntary control from the viewer. Here we used a dynamic stimulus of a rotating human body, the silhouette spinner illusion, to investigate how the viewers' intentions may affect their percepts. In two experiments, we manipulated observer intention (active or passive), fixation position (body or feet), and spinning velocity (fast, medium, or slow). Our results showed that the normalized alternating rate between two bistable percepts was greater when (1) participants actively attempted to switch percepts, (2) when participants fixated at the spinner's feet rather than the body, inducing as many as 25 switches of the bistable percepts within 1 min, and (3) when they watched the spinner at high velocity. These results suggest that a dynamic biologically-bistable percept can be quickly alternated by the viewers' intention. Furthermore, the higher alternating rate in the feet condition compared to the body condition suggests a role for biological meaningfulness in determining bistable percepts, where 'biologically plausible' interpretations are favored by the visual system., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Most people find it easy to perform rhythmic movements in synchrony with music, which reflects their ability to perceive the temporal periodicity and to allocate attention in time accordingly. Musicians and non-musicians were tested in a click localization paradigm in order to investigate how grouping and metrical accents in metrical rhythms influence attention allocation, and to reveal the effect of musical expertise on such processing. We performed two experiments in which the participants were required to listen to isochronous metrical rhythms containing superimposed clicks and then to localize the click on graphical and ruler-like representations with and without grouping structure information, respectively. Both experiments revealed metrical and grouping influences on click localization. Musical expertise improved the precision of click localization, especially when the click coincided with a metrically strong beat. Critically, although all participants located the click accurately at the beginning of an intensity group, only musicians located it precisely when it coincided with a strong beat at the end of the group. Removal of the visual cue of grouping structures enhanced these effects in musicians and reduced them in non-musicians. These results indicate that musical expertise not only enhances attention to metrical accents but also heightens sensitivity to perceptual grouping.

The possibility that during Chinese reading information is extracted at the beginning of the current fixation was examined in this study. Twenty-four participants read for comprehension while their eye movements were being recorded. A pretarget-target two-character word pair was embedded in each sentence and target word visibility was manipulated in two time intervals (initial 140 ms or after 140 ms) during pretarget viewing. Substantial beginning- and end-of-fixation preview effects were observed together with beginning-of-fixation effects on the pretarget. Apparently parafoveal information at least at the character level can be extracted relatively early during ongoing fixations. Results are highly relevant for ongoing debates on spatially distributed linguistic processing and address fundamental questions about how the human mind solves the task of reading within the constraints of different writing systems.

In two experiments, a parafoveal lexicality effect in the reading of Chinese (a script that does not physically mark word boundaries) was examined. Both experiments used the boundary paradigm (Rayner, 1975) and indicated that the lexical properties of parafoveal words influenced eye movements. In Experiment 1, the preview stimulus was either a real word or a pseudoword. Targets with word previews, even unrelated ones, were more likely to be skipped than were those with pseudowords. In Experiment 2, all of the preview stimuli had the same first character as the target. Target words with same-morpheme previews were fixated for less time than were those with pseudoword previews, suggesting that morphological processing may be involved in extracting information from parafoveal words in Chinese reading. Together, the two experiments dealing with how words are processed in Chinese may provide some constraints on current computational models of reading.

The role of phonological coding for character identification was examined with the benefit of processing parafoveal characters in eye fixations while reading Chinese sentences. In Experiment 1, the orthogonal manipulation of phonological and orthographic similarity can separate two types of phonological benefits for homophonic previews, according to whether these previews share the same phonetic radical with the targets or not. The significant phonological benefits indicate that phonological coding is activated early when the character is in the parafovea. Experiment 2 manipulated the character's consistency value and found that the phonological preview benefits are reliable only when the targets are high consistency characters. The results of two experiments suggest that phonological computation is rapid and early at both character and radical levels for Chinese character identification.