Processing visual ambiguity in fractal patterns: Pareidolia as a sign of creativity

Creativity is a complex, multifaceted and highly valued quality. Characterizing creativity experimentally is a challenging endeavor. While most studies to date have focused on divergent thinking, emerging work also points to an intricate link between creativity and perceptual abilities. Here, we hypothesized that differences in high- and low-creative individuals are already present at the level of sensory perception, specifically in the ability to perceive recognizable forms in noisy or ambiguous stimuli, a phenomenon called pareidolia. To test this, we designed a visual perception task in which 50 participants, with various levels of creativity, were presented with ambiguous stimuli and asked to identify as many recognizable forms as possible. A key manipulation consisted in generating cloud-like images where we manipulated the level of complexity by manipulating fractal dimension (FD) and contrast level. We found that pareidolic perceptions arise more often and more rapidly in creative individuals. Interestingly, less creative individuals have a narrower range of FD values that support the emergence of pareidolia. Our results show that FD and contrast are key visual properties to manipulate when investigating pareidolic perception and its putative link to creativity. They also suggest that pareidolia may be used as a perceptual proxy of idea generation abilities, a prerequisite for creative behavior. In sum, we extend the established body of work on divergent thinking, by introducing divergent perception as a complementary manifestation of the creative mind. Therefore, these findings expand our understanding of the perception-creation link and open new paths in studying creative behavior in humans.

Ambiguous Self-Induced Disinformation (ASID) Attacks: Weaponizing a Cognitive Deficiency

Humans quickly and effortlessly impose narrative context onto ambiguous stimuli, as demonstrated through psychological projective testing and ambiguous figures. We suggest that this feature of human cognition may be weaponized as part of an information operation. Such Ambiguous Self-Induced Disinformation (ASID) attacks would employ the following elements: the introduction of a culturally consistent narrative, the presence of ambiguous stimuli, the motivation for hypervigilance, and a social network. ASID attacks represent a reduced-risk, low-investment on the part of the adversary with a potentially significant reward, making this a likely tactic of choice for information operators within the context of gray-zone conflicts.

A Novel Measure of Real-Time Perseverative Thought

Perseverative thinking (PT), or repetitive negative thinking, has historically been measured using global self-report scales. New methods of assessment are needed to advance understanding of this inherently temporal process. We developed an intensive longitudinal method for assessing PT. A mixed sample of 77 individuals ranging widely in trait PT, including persons with PT-related disorders (generalized anxiety disorder, major depression) and persons without psychopathology, used a joystick to provide continuous ratings of thought valence and intensity following exposure to scenarios of differing valence. Joystick responses were robustly predicted by trait PT, clinical status, and stimulus valence. Higher trait perseverators exhibited more extreme joystick values overall, greater stability in values following threatening and ambiguous stimuli, weaker stability in values following positive stimuli, and greater inertia in values following ambiguous stimuli. The joystick method is a promising measure with the potential to shed new light on the dynamics and precipitants of perseverative thinking.

Cross-modal auditory priors drive the perception of bistable visual stimuli with reliable differences between individuals

It is a widely held assumption that the brain performs perceptual inference by combining sensory information with prior expectations, weighted by their uncertainty. A distinction can be made between higher- and lower-level priors, which can be manipulated with associative learning and sensory priming, respectively. Here, we simultaneously investigate priming and the differential effect of auditory vs. visual associative cues on visual perception, and we also examine the reliability of individual differences. Healthy individuals (N = 29) performed a perceptual inference task twice with a one-week delay. They reported the perceived direction of motion of dot pairs, which were preceded by a probabilistic visuo-acoustic cue. In 30% of the trials, motion direction was ambiguous, and in half of these trials, the auditory versus the visual cue predicted opposing directions. Cue-stimulus contingency could change every 40 trials. On ambiguous trials where the visual and the auditory cue predicted conflicting directions of motion, participants made more decisions consistent with the prediction of the acoustic cue. Increased predictive processing under stimulus uncertainty was indicated by slower responses to ambiguous (vs. non-ambiguous) stimuli. Furthermore, priming effects were also observed in that perception of ambiguous stimuli was influenced by perceptual decisions on the previous ambiguous and unambiguous trials as well. Critically, behavioural effects had substantial inter-individual variability which showed high test–retest reliability (intraclass correlation coefficient (ICC) > 0.78). Overall, higher-level priors based on auditory (vs. visual) information had greater influence on visual perception, and lower-level priors were also in action. Importantly, we observed large and stable differences in various aspects of task performance. Computational modelling combined with neuroimaging could allow testing hypotheses regarding the potential mechanisms causing these behavioral effects. The reliability of the behavioural differences implicates that such perceptual inference tasks could be valuable tools during large-scale biomarker and neuroimaging studies.

Hemifield-Specific Rotational Biases during the Observation of Ambiguous Human Silhouettes

Both static and dynamic ambiguous stimuli representing human bodies that perform unimanual or unipedal movements are usually interpreted as right-limbed rather than left-limbed, suggesting that human observers attend to the right side of others more than the left one. Moreover, such a bias is stronger when static human silhouettes are presented in the RVF (right visual field) than in the LVF (left visual field), which might represent a particular instance of embodiment. On the other hand, hemispheric-specific rotational biases, combined with the well-known bias to perceive forward-facing figures, could represent a confounding factor when accounting for such findings. Therefore, we investigated whether the lateralized presentation of an ambiguous rotating human body would affect its perceived handedness/footedness (implying a role of motor representations), its perceived spinning direction (implying a role of visual representations), or both. To this aim, we required participants to indicate the perceived spinning direction (which also unveils the perceived handedness/footedness) of ambiguous stimuli depicting humans with an arm or a leg outstretched. Results indicated that the lateralized presentation of the stimuli affected both their perceived limb laterality (a larger number of figures being interpreted as right-limbed in the RVF than in the LVF) and their perceived spinning direction (a larger number of figures being interpreted as spinning clockwise in the LVF than in the RVF). However, the hemifield of presentation showed a larger effect size on the perceived spinning direction than on the perceived limb laterality. Therefore, as we already proposed, the implicit representation of others’ handedness seems to be affected more by visual than by motor processes during the perception of ambiguous human silhouettes.

Short telomeres drive pessimistic judgement bias in zebrafish

The role of telomerase reverse transcriptase has been widely investigated in the contexts of ageing and age-related diseases. Interestingly, decreased telomerase activities (and accelerated telomere shortening) have also been reported in patients with emotion-related disorders, opening the possibility for subjective appraisal of stressful stimuli playing a key role in stress-driven telomere shortening. In fact, patients showing a pessimistic judgement bias have shorter telomeres. However, in humans the evidence for this is correlational and the causal directionality between pessimism and telomere shortening has not been established experimentally yet. We have developed and validated a judgement bias experimental paradigm to measure subjective evaluations of ambiguous stimuli in zebrafish. This behavioural assay allows classification of individuals in an optimistic–pessimistic dimension (i.e. from individuals that consistently evaluate ambiguous stimuli as negative to others that perceive them as positive). Using this behavioural paradigm we found that telomerase-deficient zebrafish ( tert − / − ) were more pessimistic in response to ambiguous stimuli than wild-type zebrafish. The fact that individuals with constitutive shorter telomeres have pessimistic behaviours demonstrates for the first time in a vertebrate model a genetic basis of judgement bias.

Can valence and origin of emotional words influence the assessments of ambiguous stimuli in terms of warmth or competence?

People tend to think that emotions influence the way they think in a spectacular way. We wanted to determine whether it is possible to prime the assessments of ambiguous stimuli by presenting emotion-laden words. We did not expect the differences in assessments that depend only on the emotional factors to be particularly large. Participants were presented with words differing in valence and origin of an affective state, but aligned for arousal, concreteness, length and frequency of use. Their first task was to remember a word. While keeping the word in mind, their second task was to guess by intuition whether the symbol was related to certain traits. Participants assessed objects represented by coding symbols on the scales of warmth or competence. We expected positive valence and automatic origin to promote higher ratings in terms of warmth and reflective origin to promote higher ratings in terms of competence. Positive valence appeared to boost assessments in terms of both warmth and competence, while the origin effect was found to be dissociative: automatic origin promoted intensity of warmth assessments and reflective origin intensity of competence assessments. The study showed an existing relation between emotional and social aspects of the mind, and therefore supports the conclusion that both domains may result from dual processes of a more general character.