A shared novelty-seeking basis for creativity and curiosity: Response to the commentators

In our target article, we proposed that curiosity and creativity are both manifestations of the same novelty-seeking process. We received 29 commentaries from diverse disciplines that add insights to our initial proposal. These commentaries ultimately expanded and supplemented our model. Here we draw attention to five central practical and theoretical issues that were raised by the commentators: (1) The complex construct of novelty and associated concepts; (2) the underlying subsystems and possible mechanisms; (3) the different pathways and subtypes of curiosity and creativity; (4) creativity and curiosity "in the wild"; (5) the possible link(s) between creativity and curiosity.

Context as a barrier: Impaired contextual processing increases the tendency to develop PTSD symptoms across repeated exposure to trauma

Growing evidence links repeated traumatic exposure with impaired ability to process contextual information. Specifically, like individuals with PTSD, non-PTSD trauma-exposed individuals fail to react according to contextual demands. In the present study, we explored the process that underlies this impairment. First, we tested the ability of first responders to benefit from contextual primes to improve recognition. Second, we assessed its moderating role in the relationship between traumatic exposure and PTSD symptoms. Fifty-three active-duty firefighters and 33 unexposed civilians matched for age, gender, and years of education participated in the study. All participants completed the contextual priming paradigm, the CAPS-5 clinical interview, and the WAIS-IV vocabulary subtest and were assessed for depression and general traumatic exposure. Repeated traumatic exposure was assessed objectively using the fire-and-rescue-service tracking system. As predicted, we found that trauma-exposed individuals failed to use primes to facilitate rapid and accurate recognition of contextually related objects. Not only did contextual information not improve performance, but it achieved the opposite effect, manifested as negative priming. Hence, context appeared to be an obstacle for trauma-exposed individuals and delayed rapid and accurate recognition. Moreover, impaired ability to process contextual information predicted the tendency to develop PTSD symptoms across repeated exposure to trauma.

A shared novelty-seeking basis for creativity and curiosity

Curiosity and creativity are central pillars of human growth and invention. Although they have been studied extensively in isolation, the relationship between them has not yet been established. We propose that both curiosity and creativity emanate from the same mechanism of novelty seeking. We first present a synthesis showing that curiosity and creativity are affected similarly by a number of key cognitive faculties such as memory, cognitive control, attention, and reward. We then review empirical evidence from neuroscience research, indicating that the same brain regions are involved in both curiosity and creativity, focusing on the interplay between three major brain networks: the default mode network, the salience network, and the executive control network. After substantiating the link between curiosity and creativity, we propose a novelty-seeking model (NSM) that underlies them and suggests that the manifestation of the NSM is governed by one's state of mind.

Therapeutic plasma exchange in multiple sclerosis patients with an aggressive relapse: an observational analysis in a high-volume center

An evidence-based treatment for a Multiple Sclerosis (MS) relapse is an intravenous administration of 3-5 g of Methylprednisolone. In case of insufficient effect or corticosteroids intolerance, the therapeutic plasma exchange (TPE) is indicated. To assess the clinical effect of TPE in treatment of relapse in patients with relapsing-remitting MS (RRMS), we enrolled 155 patients meeting the following criteria (study period: January 2011 to February 2021): (1) age > 18, (2) RRMS according to the McDonald´s 2017 criteria, (3) MS relapse and insufficient effect of corticosteroids/corticosteroids intolerance, (4) baseline EDSS < 8. Exclusion criteria: (1) progressive form of disease, (2) history of previous TPE. Following parameters were monitored: EDSS changes (before and after corticosteroid treatment, before and after TPE; EDSS after TPE was assessed at the next clinical follow-up at the MS Center), and improvement of EDSS according to the number of procedures and baseline severity of relapse. 115 females (74%) and 40 males (26%) were included. The median age was 41 years (IQR 33-47)-131 patients underwent the pulse corticosteroids treatment and TPE, while 24 patients underwent only TPE without any previous corticosteroid treatment. Median baseline EDSS was 4.5 (IQR 3.5-5.5), median EDSS after finishing steroids was 4.5 (IQR 4.0-5.5). EDSS prior to the TPE was 4.5 (IQR 4-6), EDSS after TPE was 4.5 (IQR 3.5-5.5). We observed a significant improvement in the EDSS after TPE (p < 0.001). Sex differences were seen in TPE effectiveness, with median improvement of EDSS in females being -0.5 (IQR 1-0) and in males being 0 (IQR -0.5 to 0), p = 0.048. There was no difference in EDSS improvement by age category: 18-30 years, 31-40 years, 41-50 years, > 50 (p = 0.94), nor by total TPE count (p = 0.91). In this retrospective study of patients with an aggressive relapse and insufficient effect of intravenous corticosteroid treatment, a significant effect of TPE on EDSS improvement was observed. There was no significant difference in TPE effectivity according to the number of procedures, age, nor severity of a relapse. In this cohort, TPE was more effective in females.

Constricted semantic relations in acute depression

BACKGROUND

It has been suggested that mood influences the breadth of associated information available for retrieval, with positive mood broadening and negative mood constricting the scope of associations. In this study, we asked whether this mood-associations connection is related to controlled processes which were linked to clinical symptoms in depression.

METHODS

We used the semantic priming paradigm, which allows the dissociation of automatic and controlled processes by using short and long intervals between prime and target words. We further examined whether the strength of semantic relations (weak or strong) influence the priming effects in both neurotypical and depressed individuals.

RESULTS

Experiment 1, testing neurotypical individuals, showed priming effects for strong semantically-related words regardless of interval length, but priming effects for weak semantically-related words were smaller in short intervals than in long intervals. Experiment 2, testing depressed individuals in long intervals, showed smaller priming effects for weak semantically-related words than shown by neurotypicals, but priming effects for strong semantically-related words which were comparable between the groups.

LIMITATIONS

This study cannot determine the source for the differences in priming effects between depressed individuals and neurotypicals, and further studies are needed.

CONCLUSIONS

This is the first study to show priming impairments in depressed individuals. We discuss our results in light of leading theories concerning cognitive impairment in depression, as well as the newly emerged field of digital psychiatry.

Increased associative interference under high cognitive load

Associative processing is central for human cognition, perception and memory. But while associations often facilitate performance, processing irrelevant associations can interfere with performance, for example when learning new information. The aim of this study was to explore whether associative interference is influenced by contextual factors such as resources availability. Experiments 1–3 show that associative interference increases under high cognitive load. This result generalized to both long-term and short-term memory associations, and to both explicitly learned as well as incidentally learned associations in the linguistic and pictorial domains. Experiment 4 further revealed that attention to associative information can delay one’s perceptual processing when lacking resources. Taken together, when resources diminish associative interference increases, and additionally, processing novel and ambiguous information is hindered. These findings bare relevance to other domains as well (e.g., social, educational), in which increased load or stress may prompt an undesirable bias towards prior, misleading information.

Oculomotor anticipation reveals a multitude of learning processes underlying the serial reaction time task

Sequence learning is the cognitive faculty enabling everyday skill acquisition. In the lab, it is typically measured in speed of response to sequential stimuli, whereby faster responses are taken to indicate improved anticipation. However, response speed is an indirect measure of anticipation, that can provide only limited information on underlying processes. As a result, little is known about what is learned during sequence learning, and how that unfolds over time. In this work, eye movements that occurred before targets appeared on screen in an ocular serial reaction time (O-SRT) task provided an online indication of where participants anticipated upcoming targets. When analyzed in the context of the stimuli preceding them, oculomotor anticipations revealed several simultaneous learning processes. These processes influenced each other, as learning the task grammar facilitated acquisition of the target sequence. However, they were dissociable, as the grammar was similarly learned whether a repeating sequence inhabited the task or not. Individual differences were found in how the different learning processes progressed, allowing for similar performance to be produced for different latent reasons. This study provides new insights into the processes subserving sequence learning, and a new method for high-resolution study of it.

From Objects to Unified Minds

The involvement of top-down processes in perception and cognition is widely acknowledged by now. In fields of research from predictions to inhibition, and from attentional guidance to affect, a great deal has already been charted. Integrating this newer understanding with accumulated findings from the past has made it clear that human experience is determined by a combination of both bottom-up and top-down processes. It has been proposed that the ongoing balance between their relative contribution affects a person’s entire state of mind, an overarching framework that encompasses the breadth of mental activity. According to this proposal, state of mind, in which multiple facets of mind are clumped together functionally and dynamically, orients us to the optimal state for the given circumstances. These ideas are examined here by connecting a broad array of domains in which the balance between top-down and bottom-up processes is apparent. These domains range from object recognition to contextual associations, from pattern of thought to tolerance for uncertainty, and from the default-mode network to mood. From this synthesis emerge numerous hypotheses, implications, and directions for future research in cognitive psychology, psychiatry, and neuroscience.

Perceptual decisions are biased toward relevant prior choices

Perceptual decisions are biased by recent perceptual history-a phenomenon termed 'serial dependence.' Here, we investigated what aspects of perceptual decisions lead to serial dependence, and disambiguated the influences of low-level sensory information, prior choices and motor actions. Participants discriminated whether a brief visual stimulus lay to left/right of the screen center. Following a series of biased 'prior' location discriminations, subsequent 'test' location discriminations were biased toward the prior choices, even when these were reported via different motor actions (using different keys), and when the prior and test stimuli differed in color. By contrast, prior discriminations about an irrelevant stimulus feature (color) did not substantially influence subsequent location discriminations, even though these were reported via the same motor actions. Additionally, when color (not location) was discriminated, a bias in prior stimulus locations no longer influenced subsequent location discriminations. Although low-level stimuli and motor actions did not trigger serial-dependence on their own, similarity of these features across discriminations boosted the effect. These findings suggest that relevance across perceptual decisions is a key factor for serial dependence. Accordingly, serial dependence likely reflects a high-level mechanism by which the brain predicts and interprets new incoming sensory information in accordance with relevant prior choices.

Inferior parietal lobule and early visual areas support elicitation of individualized meanings during narrative listening

INTRODUCTION

When listening to a narrative, the verbal expressions translate into meanings and flow of mental imagery. However, the same narrative can be heard quite differently based on differences in listeners' previous experiences and knowledge. We capitalized on such differences to disclose brain regions that support transformation of narrative into individualized propositional meanings and associated mental imagery by analyzing brain activity associated with behaviorally assessed individual meanings elicited by a narrative.

METHODS

Sixteen right-handed female subjects were instructed to list words that best described what had come to their minds while listening to an eight-minute narrative during functional magnetic resonance imaging (fMRI). The fMRI data were analyzed by calculating voxel-wise intersubject correlation (ISC) values. We used latent semantic analysis (LSA) enhanced with Wordnet knowledge to measure semantic similarity of the produced words between subjects. Finally, we predicted the ISC with the semantic similarity using representational similarity analysis.

RESULTS

We found that semantic similarity in these word listings between subjects, estimated using LSA combined with WordNet knowledge, predicting similarities in brain hemodynamic activity. Subject pairs whose individual semantics were similar also exhibited similar brain activity in the bilateral supramarginal and angular gyrus of the inferior parietal lobe, and in the occipital pole.

CONCLUSIONS

Our results demonstrate, using a novel method to measure interindividual differences in semantics, brain mechanisms giving rise to semantics and associated imagery during narrative listening. During listening to a captivating narrative, the inferior parietal lobe and early visual cortical areas seem, thus, to support elicitation of individual meanings and flow of mental imagery.

Natural genetic variation for expression of a SWEET transporter among wild species of Solanum lycopersicum (tomato) determines the hexose composition of ripening tomato fruit

The sugar content of Solanum lycopersicum (tomato) fruit is a primary determinant of taste and quality. Cultivated tomato fruit are characterized by near-equimolar levels of the hexoses glucose and fructose, derived from the hydrolysis of translocated sucrose. As fructose is perceived as approximately twice as sweet as glucose, increasing its concentration at the expense of glucose can improve tomato fruit taste. Introgressions of the Fgr^H allele from the wild species Solanum habrochaites (LA1777) into cultivated tomato increased the fructose-to-glucose ratio of the ripe fruit by reducing glucose levels and concomitantly increasing fructose levels. In order to identify the function of the Fgr gene, we combined a fine-mapping strategy with RNAseq differential expression analysis of near-isogenic tomato lines. The results indicated that a SWEET protein was strongly upregulated in the lines with a high fructose-to-glucose ratio. Overexpressing the SWEET protein in transgenic tomato plants dramatically reduced the glucose levels and increased the fructose : glucose ratio in the developing fruit, thereby proving the function of the protein. The SWEET protein was localized to the plasma membrane and expression of the SlFgr gene in a yeast line lacking native hexose transporters complemented growth with glucose, but not with fructose. These results indicate that the SlFgr gene encodes a plasma membrane-localized glucose efflux transporter of the SWEET family, the overexpression of which reduces glucose levels and may allow for increased fructose levels. This article identifies the function of the tomato Fgr gene as a SWEET transporter, the upregulation of which leads to a modified sugar accumulation pattern in the fleshy fruit. The results point to the potential of the inedible wild species to improve fruit sugar accumulation via sugar transport mechanisms.

SlPRA1A/RAB attenuate EIX immune responses via degradation of LeEIX2 pattern recognition receptor

Pattern recognition receptors (PRR) are plasma membrane (PM) proteins that recognize microbe-associated molecular patterns (MAMPs), triggering an immune response. PRR are classified as receptor like kinases (RLKs) or receptor like proteins (RLPs). The PM localization of PRRs, which is crucial for their availability to sense MAMPs, depends on their appropriate trafficking through the endomembrane system. Recently, we have identified SlPRA1A, a prenylated RAB acceptor type-1 (PRA1) from S. lycopersicum, as a regulator of RLP-PRR localization and protein levels. SlPRA1A overexpression strongly decreases RLP-PRR protein levels, particularly those of LeEIX2, redirecting it to the vacuole for degradation. Interestingly, SlPRA1A does not affect RLK-PRRs, indicating its activity to be specific to RLP-PRR systems. As PRA1 proteins stabilize RABs on membranes, promoting RABs activity, we aimed to identify a RAB target of SlPRA1A. Screening of a set of A. thaliana RABs revealed that AtRABA1e is able to mimic SlPRA1A activity. Through live cell imaging, we observed that SlPRA1A enhances AtRABA1e localization on SlPRA1A positive punctuated structures. These results indicate that AtRABA1e is a putative target of SlPRA1, and a co-regulator of LeEIX2 trafficking and degradation.

The default network and the combination of cognitive processes that mediate self-generated thought

Self-generated cognitions, such as recalling personal memories or empathizing with others, are ubiquitous and essential for our lives. Such internal mental processing is ascribed to the Default Mode Network, a large network of the human brain, though the underlying neural and cognitive mechanisms remain poorly understood. Here, we tested the hypothesis that our mental experience is mediated by a combination of activities of multiple cognitive processes. Our study included four functional MRI experiments with the same participants and a wide range of cognitive tasks, as well as an analytical approach that afforded the identification of cognitive processes during self-generated cognition. We showed that several cognitive processes functioned simultaneously during self-generated mental activity. The processes had specific and localized neural representations, suggesting that they support different aspects of internal processing. Overall, we demonstrate that internally directed experience may be achieved by pooling over multiple cognitive processes.

Empathy: The Role of Expectations

To what extent can we feel what someone else feels? Data from neuroscience suggest that empathy is supported by a simulation process, namely the neural activation of the same or similar regions that subserve the representation of specific states in the observer. However, expectations significantly modulate sensory input, including affective information. For example, expecting painful stimulation can decrease the neural signal and the subjective experience thereof. For an accurate representation of the other person’s state, such top-down processes would have to be simulated as well. However, this is only partly possible, because expectations are usually acquired by learning. Therefore, it is important to be aware of possible misleading simulations that lead to misinterpretations of someone’s state.