Does Temporal Integration Occur for Unrecognizable Words in Visual Crowding?

The temporal dynamics of conscious and unconscious audio-visual semantic integration

We compared the time course of cross-modal semantic effects induced by both naturalistic sounds and spoken words on the processing of visual stimuli, whether visible or suppressed form awareness through continuous flash suppression. We found that, under visible conditions, spoken words elicited audio-visual semantic effects over longer time (-1000, -500, -250 ms SOAs) than naturalistic sounds (-500, -250 ms SOAs). Performance was generally better with auditory primes, but more so with congruent stimuli. Spoken words presented in advance (-1000, -500 ms) outperformed naturalistic sounds; the opposite was true for (near-)simultaneous presentations. Congruent spoken words demonstrated superior categorization performance compared to congruent naturalistic sounds. The audio-visual semantic congruency effect still occurred with suppressed visual stimuli, although without significant variations in the temporal patterns between auditory types. These findings indicate that: 1. Semantically congruent auditory input can enhance visual processing performance, even when the visual stimulus is imperceptible to conscious awareness. 2. The temporal dynamics is contingent on the auditory types only when the visual stimulus is visible. 3. Audiovisual semantic integration requires sufficient time for processing auditory information.

Temporal integration by multi-level regularities fosters the emergence of dynamic conscious experience

The relationship between integration and awareness is central to contemporary theories and research on consciousness. Here, we investigated whether and how information integration over time, by incorporating the underlying regularities, contributes to our awareness of the dynamic world. Using binocular rivalry, we demonstrated that structured visual streams, constituted by shape, motion, or idiom sequences containing perceptual- or semantic-level regularities, predominated over their nonstructured but otherwise matched counterparts in the competition for visual awareness. Despite the apparent resemblance, a substantial dissociation of the observed rivalry advantages emerged between perceptual- and semantic-level regularities. These effects stem from nonconscious and conscious temporal integration processes, respectively, with the former but not the latter being vulnerable to perturbations in the spatiotemporal integration window. These findings corroborate the essential role of structure-guided information integration in visual awareness and highlight a multi-level mechanism where temporal integration by perceptually and semantically defined regularities fosters the emergence of continuous conscious experience.

Multiple sources of unconscious-information processing affect a single response: independent unconscious priming effects

At present there is little knowledge on whether and how multiple pieces of unconscious information can simultaneously affect a single conscious response. In the present study, we manipulated the congruency relation between a masked prime arrow and the target arrow, as well as that between masked flankers and the target arrow. The results demonstrated that the masked prime and flankers produced independent unconscious priming effects on the response to the target. In the process of studying the above phenomenon, two secondary findings were made. First, although the prime congruency effect was obtained, the flanker congruency effect was smaller when the flankers were displayed simultaneously with the target than when they were displayed sequentially before the target. This suggested that priming stimulation required enough time to be processed to a sufficient extent to produce an unconscious priming effect. Second, when the prime stimulus was removed, leaving only the flankers, the flanker priming effect increased, suggesting that the attention attracted to the prime and its conscious mask could also reduce the flanker congruency effect. These results observed across several experiments were replicated in one within-subjects experiment. We proposed an "independent unconscious influence hypothesis" for the phenomenon. This hypothesis was further integrated into a more comprehensive unconscious information processing model. The possible causes of the observed phenomena were discussed.

The Unconscious Tug-of-War: Exploring the Effect of Stimulus Selection Bias on Creative Problem Solving with Multiple Unconscious Stimuli

Objective

This study innovatively investigated the potential selection bias involved in processing multiple subliminal stimuli during creative problem-solving (CPS). It addresses the existing gap in specialized research on how the handling of multiple unconscious stimuli influences higher-order cognitive processes, particularly creativity.

Methods

The study utilized a masked priming paradigm and a remote association task (RAT). Two experiments were conducted. Experiment 1 presented two stimuli simultaneously, with one being the correct answer, to examine whether there was a bias in the location of subliminal stimuli. In Experiment 2, two stimuli were presented sequentially, with one serving as the answer, to investigate whether there was a temporal bias in unconscious processing.

Results

Our findings revealed that when solving easy RATs, subliminal stimuli presented on the left side had a negative priming effect compared to the right side. The results revealed that unconscious processing of subliminal stimuli enhanced performance on difficult CPS. Additionally, a temporal bias was observed, with more recent subliminal stimuli having a stronger effect than earlier stimuli.

Conclusion

Unconscious processing can improve CPS, especially for difficult tasks, and there is a bias towards processing stimuli on the left and more recently presented stimuli. These findings contribute to our understanding of unconscious processing, particularly the processing of multiple subliminal stimuli in CPS, and provide insights into the biases that exist in unconscious processing.

Unconscious integration: Current evidence for integrative processing under subliminal conditions

Integrative processing is traditionally believed to be dependent on consciousness. While earlier studies within the last decade reported many types of integration under subliminal conditions (i.e. without perceptual awareness), these findings are widely challenged recently. This review evaluates the current evidence for 10 types of subliminal integration that are widely studied: arithmetic processing, object-context integration, multi-word processing, same-different processing, multisensory integration and 5 different types of associative learning. Potential methodological issues concerning awareness measures are also taken into account. It is concluded that while there is currently no reliable evidence for subliminal integration, this does not necessarily refute 'unconscious' integration defined through non-subliminal (e.g. implicit) approaches.

Role of visual awareness on semantic integration of sequentially presented words: An fMRI study

Reading comprehension requires the semantic integration of words across space and time. However, it remains unclear whether comprehension requires visual awareness for such semantic integration. Compared to earlier studies that investigated semantic integration indirectly from its priming effect, we used functional magnetic resonance imaging (fMRI) to directly examine the processes of semantic integration with or without visual awareness. Specifically, we manipulated participants' visual awareness by continuous flash suppression (CFS) while they viewed a meaningful sequence of four Chinese words (i.e., an idiom) or its meaningless counterpart (i.e., a random sequence). Behaviorally, participants had better recognition memory for idioms than random sequences only when their visual awareness was interfered rather than blocked by CFS. Neurally, semantics-processing areas, such as the superior temporal gyrus and inferior frontal gyrus, were significantly activated only when participants were aware of word sequences, be they meaningful or meaningless. By contrast, orthography-processing areas, such as the fusiform gyrus and inferior occipital gyrus, were significantly activated regardless of visual awareness or word sequence. Taken together, these results suggest that visual awareness modules the functioning of the semantic neural network in the brain and facilitates reading comprehension.

Age-Related Differences in the Neural Processing of Idioms: A Positive Perspective

We examined whether older adults benefit from a larger mental-lexicon size and world knowledge to process idioms, one of few abilities that do not stop developing until later adulthood. Participants viewed four-character sequences presented one at a time that combined to form (1) frequent idioms, (2) infrequent idioms, (3) random sequences, or (4) perceptual controls, and judged whether the four-character sequence was an idiom. Compared to their younger counterparts, older adults had higher accuracy for frequent idioms and equivalent accuracy for infrequent idioms. Compared to random sequences, when processing frequent and infrequent idioms, older adults showed higher activations in brain regions related to sematic representation than younger adults, suggesting that older adults devoted more cognitive resources to processing idioms. Also, higher activations in the articulation-related brain regions indicate that older adults adopted the thinking-aloud strategy in the idiom judgment task. These results suggest re-organized neural computational involvement in older adults' language representations due to life-long experiences. The current study provides evidence for the alternative view that aging may not necessarily be solely accompanied by decline.

Accessing Semantic Information from Above: Parafoveal Processing during the Reading of Vertically Presented Sentences in Traditional Chinese

As traditional Chinese readers are familiar with reading texts both horizontally rightwards and vertically downwards, the traditional Chinese script provides us a chance to investigate the influence of reading direction on preview benefits by ruling out the confounding factor of different familiarities with reading directions. The present study examines whether parafoveal information can be obtained when reading Chinese sentences in the vertical direction. We manipulated semantic and phonological relatedness between parafoveal preview words and target words. Results showed that traditional Chinese readers could obtain semantic information from preview words; however, there was no phonological preview benefit. Our findings agree with the notion that Chinese characters are well-optimized for semantic access.

Windows of Integration Hypothesis Revisited

In the ongoing research of the functions of consciousness, special emphasis has been put on integration of information: the ability to combine different signals into a coherent, unified one. Several theories of consciousness hold that this ability depends on - or at least goes hand in hand with - conscious processing. Yet some empirical findings have suggested otherwise, claiming that integration of information could take place even without awareness. Trying to reconcile this apparent contradiction, the "windows of integration" (WOI) hypothesis claims that conscious access enables signal processing over large integration windows. The hypothesis applies to integration windows defined either temporally, spatially, or semantically. In this review, we explain the hypothesis and re-examine it in light of new studies published since it was suggested. In line with the hypothesis, these studies provide compelling evidence for unconscious integration, but also demonstrate its limits with respect to time, space, and semantic distance. The review further highlights open questions that still need to be pursued to demonstrate the applicability of the WOI hypothesis as a guiding principle for understanding the depth and scope of unconscious processes.