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Computer-based dreams content analysis relies on word frequencies within predefined categories in order to identify different elements in text. As a complementary approach, we explored the capabilities and limitations of word-embedding techniques to identify word usage patterns among dream reports. These tools allow us to quantify words associations in text and to identify the meaning of target words. Word-embeddings have been extensively studied in large datasets, but only a few studies analyze semantic representations in small corpora. To fill this gap, we compared Skip-gram and Latent Semantic Analysis (LSA) capabilities to extract semantic associations from dream reports. LSA showed better performance than Skip-gram in small size corpora in two tests. Furthermore, LSA captured relevant word associations in dream collection, even in cases with low-frequency words or small numbers of dreams. Word associations in dreams reports can thus be quantified by LSA, which opens new avenues for dream interpretation and decoding. [ABSTRACT FROM AUTHOR]

Individuals differ in their ability to attribute actions to self or other. This variance is thought to explain, in part, the experience of voice-hearing. Misattribution can also be context-driven. For example, causal ambiguity can arise when the actions of two or more individuals are coordinated and produce similar effects (e.g., music-making). Experience in such challenging contexts may refine skills of action attribution. Forty participants completed a novel finger-tapping task which parametrically manipulated the proportion of control that ‘self’ versus ‘other’ possessed over resulting auditory tones. Results showed that action misattribution peaked in the middle of the self-to-other continuum and was biased towards other. This pattern was related to both high hallucination-proneness and to low musical-experience. Findings suggest not only that causal ambiguity plays a key role in agency but also that action attribution abilities may improve with practice, potentially providing an avenue for remediation of the positive symptoms of schizophrenia. [ABSTRACT FROM AUTHOR]

Performance on tasks requiring discrimination of at least two stimuli can be viewed either from an objective perspective (referring to actual stimulus differences), or from a subjective perspective (corresponding to participant’s responses). Using event-related potentials recorded during an old/new recognition memory test involving emotionally laden and neutral words studied either blockwise or randomly intermixed, we show here how the objective perspective (old versus new items) yields late effects of blockwise emotional item presentation at parietal sites that the subjective perspective fails to find, whereas the subjective perspective (“old” versus “new” responses) is more sensitive to early effects of emotion at anterior sites than the objective perspective. Our results demonstrate the potential advantage of dissociating the subjective and the objective perspective onto task performance (in addition to analyzing trials with correct responses), especially for investigations of illusions and information processing biases, in behavioral and cognitive neuroscience studies. [ABSTRACT FROM AUTHOR]

Highlights: [•] Paranormal believers show a response bias for ‘yes’ in a biological motion detection task. [•] Belief in the paranormal is related to illusory agency detection for stimuli of low ambiguity. [•] Illusory agency detection is primarily related to paranormal beliefs, but not to religious beliefs. [ABSTRACT FROM AUTHOR]

Highlights: [•] The temporal relation of inducer identification and color emergence was explored. [•] W/M and 6/9 were presented at varying angles to color-graphemic synesthetes. [•] Synesthetes were slower naming the experienced color than identifying the character. [•] The degree of ambiguity tended to interact with slowed response in “color” naming. [ABSTRACT FROM AUTHOR]

Abstract: Affect misattribution occurs when affective cues color subsequent unrelated evaluations. Research suggests that affect misattribution decreases when one is aware that affective cues are unrelated to the evaluation at hand. We propose that affect misattribution may even occur when one is aware that affective cues are irrelevant, as long as the source of these cues seems ambiguous. When source ambiguity exists, affective cues may freely influence upcoming unrelated evaluations. We examined this using an adapted affect misattribution procedure where pleasant and unpleasant responses served as affective cues that could influence later evaluations of unrelated targets. These affective cues were either perceived as reflecting a single source (i.e., a subliminal affective picture in Experiment 1; one’s internal affective state in Experiment 2), or as reflecting two sources (i.e., both) suggesting source ambiguity. Results show that misattribution of affect decreased when participants perceived affective cues as representing one source rather than two. [Copyright &y& Elsevier]

Abstract: In timing perception studies, the timing of one event is usually manipulated relative to another, and participants are asked to judge if the two events were synchronous, or to judge which of the two events occurred first. Responses are analyzed to determine a measure of central tendency, which is taken as an estimate of the timing at which the two events are perceptually synchronous. When these estimates do not coincide with physical synchrony, it is often assumed that the sensory signals are asynchronous, as though the transfer of information concerning one input has been accelerated or decelerated relative to the other. Here we show that, while this is a viable interpretation, it is equally plausible that such effects are driven by shifts in the criteria used to differentiate simultaneous from asynchronous inputs. Our analyses expose important ambiguities concerning the interpretation of simultaneity judgement data, which have hitherto been underappreciated. [Copyright &y& Elsevier]

Abstract: Homonyms, i.e. ambiguous words like ‘score’, have different meanings in different contexts. Previous research indicates that all potential meanings of a homonym are first accessed in parallel before one of the meanings is selected in a competitive race. If these processes are automatic, these processes of selection should even be observed when homonyms are shown subliminally. This study measured the time course of subliminal and supraliminal priming by homonyms with a frequent (dominant) and a rare (subordinate) meaning in a neutral context, using a lexical decision task. In the subliminal condition, priming across prime-target asynchronies ranging from 100ms to 1.5s indicated that the dominant meaning of homonyms was facilitated and the subordinate meaning was inhibited. This indicates that selection of meaning was much faster with subliminal presentation than with supraliminal presentation. Awareness of a prime might decelerate an otherwise rapid selection process. [Copyright &y& Elsevier]

Abstract: Flickering light induces visual hallucinations in human observers. Despite a long history of the phenomenon, little is known about the dependence of flicker-induced subjective impressions on the flicker frequency. We investigate this question using Ganzfeld stimulation and an experimental paradigm combining a continuous frequency scan (1–50Hz) with a focus on re-occurring, whole percepts. On the single-subject level, we find a high degree of frequency stability of percepts. To generalize across subjects, we apply two rating systems, (1) a set of complex percept classes derived from subjects’ reports and (2) an enumeration of elementary percept features, and determine distributions of occurrences over flicker frequency. We observe a stronger frequency specificity for complex percept classes than elementary percept features. Comparing the similarity relations among percept categories to those among frequency profiles, we observe that though percepts are preferentially induced by particular frequencies, the frequency does not unambiguously determine the experienced percept. [Copyright &y& Elsevier]

One of the primordial functions of the brain is the acquisition of knowledge. The apparatus that it has evolved to do so is flexible enough to allow it to acquire knowledge about unambiguous conditions on the one hand (colour vision being a good example), and about situations that are capable of two or more interpretations, each one of which has equal validity with the others. However, in the latter instance, we can only be conscious of one interpretation at any given moment. The study of ambiguity thus gives us some insights into how activity at different stations of the brain can result in a micro-consciousness for an attribute, and also tell us something about interactions between different cerebral areas that result in several potential micro-conscious correlates, though only one predominates at any given time. Finally, the study of ambiguity also gives us insights into the neurological machinery that artists have tapped to create the ambiguity that is commonly a hallmark of great works of art. [Copyright &y& Elsevier]