Beta oscillation is an indicator for two patterns of sensorimotor synchronization.

Previous study indicates that there are two distinct behavioral patterns in the sensory-motor synchronization task with short stimulus onset asynchrony (SOA; 2-3 s) or long SOA (beyond 4 s). However, the underlying neural indicators and mechanisms have not been elucidated. The present study applied magnetoencephalography (MEG) technology to examine the functional role of several oscillations (beta, gamma, and mu) in sensorimotor synchronization with different SOAs to identify a reliable neural indicator. During MEG recording, participants underwent a listening task without motor response, a sound-motor synchronization task, and a motor-only continuation task. These tasks were used to explore whether and how the activity of oscillations changes across different behavioral patterns with different tempos. Results showed that during both the listening and the synchronization task, the beta oscillation changes with the tempo. Moreover, the event-related synchronization of beta oscillations was significantly correlated with motor timing during synchronization. In contrast, mu activity only changes with the tempo in the synchronization task, while the gamma activity remains unchanged. In summary, the current study indicates that beta oscillation could be an indicator of behavioral patterns between fast tempo and slow tempo in sensorimotor synchronization. Also, it is likely to be the potential mechanism of maintaining rhythmic continuous movements with short SOA, which is embedded within the 3 s time window.

Composing in the scanner: A functional magnetic resonance imaging single case study on visual and auditory imagery.

"Seeing with the mind's eye" and "hearing with the mind's ear" are two common indicators of musical imagery, and they can be referred to as "visual" and "auditory" musical imagery. However, a question remains open, that is, whether visual and auditory imagery of the same musical composition share the same neural mechanisms. Moreover, how can neural mechanisms guarantee the temporal flow of "musical imagery"? To answer these questions, we report here a preliminary single case study using functional magnetic resonance imaging with an eminent composer who imagined one of his compositions in two states of mind as compared to his resting-state activity. In the visual imagery condition, he imagined visually the score of his composition in a continuous way. In the auditory imagery condition, he imagined auditorily the same musical composition with pauses. In spite of the modality and temporal differences, the two types of mental imagery showed similar temporal durations for the same musical composition. However, different patterns of neural activation were observed for visual and auditory imagery with one important exception, that is, a common activation pattern was observed in the left medial temporal gyrus in both visual and auditory imagery. We speculate that the left medial temporal gyrus may play an important role in the creation of apparent temporal continuity in musical imagery and perhaps even in conscious information processing in general.

The neural determinants of beauty.

The perception of faces correlates with activity in a number of brain areas, but only when a face is perceived as beautiful is the medial orbitofrontal cortex (mOFC) also engaged. Here, we enquire whether it is the emergence of a particular pattern of neural activity in face perceptive areas during the experience of a face as beautiful that determines whether there is, as a correlate, activity in mOFC. Seventeen subjects of both genders viewed and rated facial stimuli according to how beautiful they perceived them to be while the activity in their brains was imaged with functional magnetic resonance imaging. A univariate analysis revealed parametrically scaled activity within several areas, including the occipital face area (OFA), fusiform face area (FFA) and the cuneus; the strength of activity in these areas correlated with the declared intensity of the aesthetic experience of faces; multivariate analyses showed strong patterns of activation in the FFA and the cuneus and weaker patterns in the OFA and the posterior superior temporal sulcus (pSTS). The mOFC was only engaged when specific patterns of activity emerged in these areas. A psychophysiological interaction analysis with mOFC as the seed area revealed the involvement of the right FFA and the right OFA. We conjecture that it is the collective specific pattern-based activity in these face perceptive areas, with activity in the mOFC as a correlate, that constitutes the neural basis for the experience of facial beauty, bringing us a step closer to understanding the neural determinants of aesthetic experience.

Temporal twilight zone and beyond: Timing mechanisms in consciously delayed actions.

Precise timing is essential for many kinds of human behavior. When a fastest response is not required, movements are initiated at the appropriate time requiring an anticipatory temporal component. Temporal mechanisms for movements with such an anticipatory component are not yet sufficiently understood; in particular, it is not known whether on the operational level for delayed movements distinct time windows are used or whether anticipatory control is characterized by continuous temporal processing. With a modified reaction-time paradigm, we asked participants to act with predefined time delays between 400 and 5000 ms; after each individual trial, a numerical feedback was provided which allowed correction of the response time for each next trial. Visual stimuli (Experiment 1) and auditory stimuli (Experiment 2) were used. In the statistical analyses, piecewise linear models and exponential decay models for the response variability of different delay times were compared. These analyses favored piecewise linear models; a decreasing variability with increasing delay of voluntary controlled actions was observed up to ~1 s, followed by close to constant variability beyond this delay. We suggest that precise temporal control of voluntary delayed movements is reached only after a "temporal twilight zone" of ~1 s, which apparently marks a temporal border between two different timing mechanisms.

Aesthetic Experiences Across Cultures: Neural Correlates When Viewing Traditional Eastern or Western Landscape Paintings.

Compared with traditional Western landscape paintings, Chinese traditional landscape paintings usually apply a reversed-geometric perspective and concentrate more on contextual information. Using functional magnetic resonance imaging (fMRI), we discovered an intracultural bias in the aesthetic appreciation of Western and Eastern traditional landscape paintings in European and Chinese participants. When viewing Western and Eastern landscape paintings in an fMRI scanner, participants showed stronger brain activation to artistic expressions from their own culture. Europeans showed greater activation in visual and sensory-motor brain areas, regions in the posterior cingulate cortex (PCC), and hippocampus when viewing Western compared to Eastern landscape paintings. Chinese participants exhibited greater neural activity in the medial and inferior occipital cortex and regions of the superior parietal lobule in response to Eastern compared to Western landscape paintings. On the behavioral level, the aesthetic judgments also differed between Western and Chinese participants when viewing landscape paintings from different cultures; Western participants showed for instance higher valence values when viewing Western landscapes, while Chinese participants did not show this effect when viewing Chinese landscapes. In general, our findings offer differentiated support for a cultural modulation at the behavioral level and in the neural architecture for high-level aesthetic appreciation.

Does cue processing modulate inhibition of return in a detection task?

While the abrupt onset of a peripheral visual cue usually leads to speeded responses to following targets at the cued relative to other positions, responses are slowed if targets lag behind the cue by more than ~200 ms. This response delay is termed inhibition of return (IOR) and has been considered as a mechanism to orient behavior toward novel areas. IOR has been found in both detection and discrimination tasks with later onset in discrimination tasks, probably due to a higher processing demand. Here we examined whether the processing demand of cues can modulate IOR in the detection task. The task to the peripheral cues, either color or gap cues, was passive viewing in one session (single task) and discrimination in another session (dual task). The results showed that the time course of IOR was resistant to the cue processing, while the magnitude of IOR was increased when the processing load became larger in the dual task relative to the single task. These results indicate that IOR in target detection is both reflexive in that its temporal dynamics remain invariant, and flexible in that its magnitude is modulated by task requirement.

Attentional modulation of speed-change perception in the perifoveal and near-peripheral visual field.

The ability to perceive changes in motion, such as rapid changes of speed, has important ecological significance. We show that exogenous and endogenous attention have different effects on speed-change perception and operate differently in different regions of the visual field. Using a spatial-cueing paradigm, with either exogenous or endogenous cues followed by drifting Gabor patches of changing speed that appear at the cued or uncued location, we measured participants' thresholds for localizing both acceleration and deceleration of the Gabor patches in different regions (5° and 10°) of the visual field. The results revealed a larger exogenous cueing effect, indexed by a lower threshold for the cued relative to the uncued conditions, at 5° for perceiving acceleration and at 10° for perceiving deceleration. Endogenous attention, in contrast, improved performance equally at both eccentricities. We conclude that exogenous and endogenous spatial orienting constitute two independent attentional systems, with distinct modulation patterns on speed change perception in the visual field. While exogenous attentional modulation is eccentricity-dependent, endogenous attention acts homogeneously in perifoveal and near-peripheral regions of the visual field.

Sadness and happiness are amplified in solitary listening to music.

Previous studies have shown that music is a powerful means to convey affective states, but it remains unclear whether and how social context shape the intensity and quality of emotions perceived in music. Using a within-subject design, we studied this question in two experimental settings, i.e. when subjects were alone versus in company of others without direct social interaction or feedback. Non-vocal musical excerpts of the emotional qualities happiness or sadness were rated on arousal and valence dimensions. We found evidence for an amplification of perceived emotion in the solitary listening condition, i.e. happy music was rated as happier and more arousing when nobody else was around and, in an analogous manner, sad music was perceived as sadder. This difference might be explained by a shift of attention in the presence of others. The observed interaction of perceived emotion and social context did not differ for stimuli of different cultural origin.

The "third abstraction" of the Chinese artist LaoZhu: Neural and behavioral indicators of aesthetic appreciation.

The eminent Chinese artist LaoZhu has created a homogeneous set of abstract pictures that are referred to as the "third abstraction." By definition, these pictures are meant to be representations of the artist's personal involvement and as such to create an internal point of view in the observer on an implicit level of processing. Aiming at investigating whether the artist's choice of a specific color is experienced in a specific way in the recipient, we assessed both explicit and implicit (i.e. neurocognitive) correlates in naive viewers of LaoZhu's pieces. The behavioral results reveal a preference of the original red paintings over color-changed counterparts in green or black. Paradoxically and inconsistent with predictions, we found higher levels of neural activation in several brain regions (predominantly in the frontal and parietal cortices) for the color-changed compared to the original red conditions. These observations add empirically to the complementarity of early visual pathways and higher-order cognition as well as of explicit and implicit information processing during aesthetic appreciation. We discuss our findings in light of processing effort and top-down control of the color-changed paintings. With regard to the third abstraction as defined by LaoZhu, in particular to the distinction between an external and internal point of view when viewing abstract art, our results contribute to an understanding of "abstraction and empathy" as a fundamental part of aesthetic appreciations.

Aesthetic Preferences for Eastern and Western Traditional Visual Art: Identity Matters.

Western and Chinese artists have different traditions in representing the world in their paintings. While Western artists start since the Renaissance to represent the world with a central perspective and focus on salient objects in a scene, Chinese artists concentrate on context information in their paintings, mainly before the mid-19th century. We investigated whether the different typical representations influence the aesthetic preference for traditional Chinese and Western paintings in the different cultural groups. Traditional Chinese and Western paintings were presented randomly for an aesthetic evaluation to Chinese and Western participants. Both Chinese and Western paintings included two categories: landscapes and people in different scenes. Results showed a significant interaction between the source of the painting and the cultural group. For Chinese and Western paintings, a reversed pattern of aesthetic preference was observed: while Chinese participants gave higher aesthetic scores to traditional Chinese paintings than to Western paintings, Western participants tended to give higher aesthetic scores to traditional Western paintings than to Chinese paintings. We interpret this observation as indicator that personal identity is supported and enriched within cultural belongingness. Another important finding was that landscapes were more preferable than people in a scene across different cultural groups indicating a universal principle of preferences for landscapes. Thus, our results suggest that, on the one hand, the way that artists represent the world in their paintings influences the way that culturally embedded viewers perceive and appreciate paintings, but on the other hand, independent of the cultural background, anthropological universals are disclosed by the preference of landscapes.

Seeing without knowing: Operational principles along the early visual pathway.

UNLABELLED: Single cases may lead to unexpected hypotheses in psychology. We retrospectively analyzed single case studies that suggested organizational principles along the early visual pathway, which have remained unanswered until now. FIRST CASE: In spite of the inhomogeneity of sensitivity, paradoxically the visual field on the subjective level appears to be homogeneous; constancy of brightness of supra-threshold stimuli throughout the visual field is claimed to be responsible for homogeneity; specific summation properties of retinal ganglion cells are hypothesized to guarantee this effect. SECOND CASE: With a brain-injured patient having suffered a partial visual field loss it can be shown that color induction is a retinal phenomenon; lateral inhibitory processes at the level of amacrine cells are hypothesized as neural network. Third case: In a patient having suffered a bilateral occipital lobe infarction, some functional recovery has been demonstrated; divergence and convergence of projection in the ascending neural pathway are suggested as a structural basis for recovery. Slowed down binocular rivalry discloses a sequential mechanism in the construction of a visual percept. Fourth case: The pre-wired projection of the retina to the visual cortex in spite of a severe squint of one eye is confirmed, but paradoxically some local neuroplasticity is also suggested. Fifth case: Using habituation of local sensitivity in the visual field and its resetting by interhemispheric interactions as an experimental paradigm, it is suggested that spatial attention is controlled at the midbrain level. Sixth case: Observations on residual vision or "blindsight" support the hypothesis that the visual cortex is the one and only structure responsible for visual perception on a conscious level. The unifying principle of these retrospective analyses is that subjective visual phenomena can lead to unexpected but testable hypotheses of neural processing on the structural and functional level in the early visual pathway.

Donders revisited: Discrete or continuous temporal processing underlying reaction time distributions?

Differences of reaction times to specific stimulus configurations are used as indicators of cognitive processing stages. In this classical experimental paradigm, continuous temporal processing is implicitly assumed. Multimodal response distributions indicate, however, discrete time sampling, which is often masked by experimental conditions. Differences in reaction times reflect discrete temporal mechanisms that are pre-semantically implemented and suggested to be based on entrained neural oscillations.

Synchronization as a biological, psychological and social mechanism to create common time: A theoretical frame and a single case study.

Synchronizing neural processes, mental activities, and social interactions is considered to be fundamental for the creation of temporal order on the personal and interpersonal level. Several different types of synchronization are distinguished, and for each of them examples are given: self-organized synchronizations on the neural level giving rise to pre-semantically defined time windows of some tens of milliseconds and of approximately 3 s; time windows that are created by synchronizing different neural representations, as for instance in aesthetic appreciations or moral judgments; and synchronization of biological rhythms with geophysical cycles, like the circadian clock with the 24-hr rhythm of day and night. For the latter type of synchronization, an experiment is described that shows the importance of social interactions for sharing or avoiding common time. In a group study with four subjects being completely isolated together for 3 weeks from the external world, social interactions resulted both in intra- and interindividual circadian synchronization and desynchronization. A unique phenomenon in circadian regulation is described, the "beat phenomenon," which has been made visible by the interaction of two circadian rhythms with different frequencies in one body. The separation of the two physiological rhythms was the consequence of social interactions, that is, by the desire of a subject to share and to escape common time during different phases of the long-term experiment. The theoretical arguments on synchronization are summarized with the general statement: "Nothing in cognitive science makes sense except in the light of time windows." The hypothesis is forwarded that time windows that express discrete timing mechanisms in behavioral control and on the level of conscious experiences are the necessary bases to create cognitive order, and it is suggested that time windows are implemented by neural oscillations in different frequency domains.

Spatial orienting around the fovea: exogenous and endogenous cueing effects.

The effect of covert attention in perifoveal and peripheral locations has been studied extensively. However, it is less clear whether attention operates similarly in the foveal area itself. The present study aims to investigate whether the attentional orienting elicited by an exogenous or endogenous cue can operate within the foveal area and whether attentional orienting operates similarly between foveal and perifoveal regions. By manipulating exogenous orienting in Experiment 1 and endogenous orienting in Experiment 2, we observed both forms of cueing in the foveal area. Specifically, we observed a larger exogenous cue-induced inhibitory effect (i.e., inhibition of return effect) and a similar endogenous cue-elicited facilitatory effect for the perifoveal relative to the foveal targets. We conclude that exogenous and endogenous orienting subject to two independent attentional systems with distinct modulation patterns in the foveal area.

Auditory perception of temporal order: A comparison between tonal language speakers with and without non-tonal language experience.

It has been shown recently that temporal order perception is modulated by language environments. The present study focused on the specific question whether a secondary language experience influences temporal order perception by comparing the temporal order thresholds (TOTs) between Chinese subjects with and without a secondary non-tonal language (i.e., English) experience. Besides monaurally presented paired clicks, binaurally presented two different types of tone pairs were used in order to better capture a potential difference between tonal and non-tonal languages. The results showed a non-significant language effect on monaurally presented click TOTs, but a significant language effect for binaurally presented tone TOTs. Compared to click performance, Chinese subjects without English proficiency demonstrated a significantly lower TOT only for close frequency tone pairs, while Chinese subjects with English proficiency demonstrated lower TOTs for both close frequency and distant frequency tone pairs. These results confirm on the one hand a common and language independent temporal mechanism for perceiving the order of two monaurally presented stimuli, and indicate on the other hand specific mechanisms of neuronal plasticity for perceiving the order of frequency-related auditory stimuli for tonal language speakers with or without a secondary non-tonal language experience.