The brain in flow: a systematic review on the neural basis of the flow state

Background: Flow state is a subjective experience that people report when task performance is experienced as automatic, intrinsically rewarding, optimal and effortless. While this intriguing phenomenon is the subject of a plethora of behavioural studies, only recently researchers have started to look at its neural correlates. Here, we aim to systematically and critically review the existing literature on the neural correlates of the flow state. Methods: Three electronic databases (Web of Science, Scopus and PsycINFO) were searched to acquire information on eligible articles in July, 2021, and updated in March, 2022. Studies that measured or manipulated flow state (through questionnaires or employing experimental paradigms) and recorded associated brain activity with electroencephalography (EEG), functional magnetic resonance (fMRI) or functional near-infrared spectroscopy (fNIRS) or manipulated brain activity with transcranial direct current stimulation (tDCS) were selected. We used the Cochrane Collaboration Risk of Bias 2 (RoB 2) tool to assess the methodological quality of eligible records. Results: In total, 25 studies were included, which involved 471 participants. In general, the studies that experimentally addressed flow state and its neural dynamics seem to converge on the key role of structures linked to attention, executive function and reward systems, giving to the anterior brain areas (e.g., the DLPC, MPFC, IFG) a crucial role in the experience of flow. However, the dynamics of these brain regions during flow state are inconsistent across studies. Discussion: In light of the results, we conclude that the current available evidence is sparse and inconclusive, which limits any theoretical debate. We also outline major limitations of this literature (the small number of studies, the high heterogeneity across them and their important methodological constraints) and highlight several aspects regarding experimental design and flow measurements that may provide useful avenues for future studies on this topic.Spanish Government 20CO1/012863Ministry of Science and Innovation, Spain (MICINN) Spanish Government PID2019-105635GBI00Junta de Andalucia DOC_0022

Snail1 protein in the stroma as a new putative prognosis marker for colon tumours

Peer reviewe

Snail1 expression is required for sarcomagenesis

Altres ajuts: Fundació La Marató de TV3 (120130)Snail1 transcriptional repressor is a major inducer of epithelial-to mesenchymal transition but is very limitedly expressed in adult animals. We have previously demonstrated that Snail1 is required for the maintenance of mesenchymal stem cells (MSCs), preventing their premature differentiation. Now, we show that Snail1 controls the tumorigenic properties of mesenchymal cells. Increased Snail1 expression provides tumorigenic capabilities to fibroblastic cells; on the contrary, Snail1 depletion decreases tumor growth. Genetic depletion of Snail1 in MSCs that are deficient in p53 tumor suppressor downregulates MSC markers and prevents the capability of these cells to originate sarcomas in immunodeficient SCID mice. Notably, an analysis of human sarcomas shows that, contrarily to epithelial tumors, these neoplasms display high Snail1 expression. This is particularly clear for undifferentiated tumors, which are associated with poor outcome. Together, our results indicate a role for Snail1 in the generation of sarcomas

Redundancy effect of multisensory interactions under reduced alertness

A basic principle of multisensory research posits that our ability to make adaptive responses arises from the combined action of our senses in producing a coherent multimodal representation of the external world by exploiting redundancies. This beneficial multisensory phenomenon, called the “redundancy effect”, manifests behaviourally as faster responses when two redundant stimuli (from different senses) appear together, as compared to when a single stimulus appears. Despite extensive research has repeatedly shown this effect, it is not clear whether it is modulated by the individual’s level of alertness, and if so (as hypothesised), to what extent it affects early sensory integration or later perceptual processing. In this experiment, we will combine computational modelling and EEG to determine whether audio-tactile interactions occur via similar spatiotemporal neural mechanisms under reduced alertness

The brain in flow: a systematic review on the neural basis of the flow state

Background: Flow state is a subjective experience that people report when task performance is experienced as automatic, intrinsically rewarding, optimal and effortless. While this intriguing phenomenon is the subject of a plethora of behavioural studies, only recently researchers have started to look at its neural correlates. Here, we aim to systematically and critically review the existing literature on the neural correlates of the flow state. Methods: Three electronic databases (Web of Science, Scopus and PsycINFO) were searched to acquire information on eligible articles in July, 2021, and updated in March, 2022. Studies that measured or manipulated flow state (through questionnaires or employing experimental paradigms) and recorded associated brain activity with electroencephalography (EEG), functional magnetic resonance (fMRI) or functional near-infrared spectroscopy (fNIRS) or manipulated brain activity with transcranial direct stimulation (tDCS) were selected. We used the Cochrane Collaboration Risk of Bias 2 (RoB 2) tool to assess the methodological quality of eligible records. Results: In total, 25 studies were included, which involved 471 participants. In general, the studies that experimentally addressed flow state and its neural dynamics seem to converge on the key role of structures linked to attention, executive function and reward systems, giving to the anterior brain areas (e.g., the DLPC, MPFC, IFG) a crucial role in the experience of flow. However, the dynamics of these brain regions during flow state are inconsistent across studies. Discussion: In light of the results, we conclude that the current available evidence is sparse and inconclusive, which limits any theoretical debate. We also outline major limitations of this literature (the small number of studies, the high heterogeneity across them and their important methodological constraints) and highlight several aspects regarding experimental design and flow measurements that may provide useful avenues for future studies on this topic

Characterising the mechanisms underlying cognitive control in high and low arousal states

Throughout two different experiments, we implemented an auditory Simon task to healthy participants in a natural state of either transition into sleep (drowsiness) or physical extenuation (high-intensity physical exercise) to study the behavioural dynamics of cognitive control during non-pharmacological altered arousal states. Databases from both experiments were combined. Reaction times and accuracy data were fitted using multilevel linear mixed-effects modelling (as implemented in the lme4 R package; Bates et al., 2014). We also applied a diffusion model for conflict tasks (DMC; Ulrich et al., 2015), by implementing the DMCfun package in R (Mackenzie & Dudschig, 2021)

Expression of Snail1 in tumor and stroma according to tumor stage.

<p>Snail1 immunoreactivity was determined in the stromal or carcinoma cells corresponding to colorectal tumours classified in the different stages. According to Snail1 expression, tumours were classified as presenting Snail1 expression both in the tumour and stroma (T+/S+), just in the tumour (T+/S−), just in the stroma (T−/S+) or not present in either of these compartments (T−/S−).</p

Nuclear Snail1 protein expression in colon carcinomas.

<p>Expression of Snail protein was determined as indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005595#s4" target="_blank">Methods</a> in samples corresponding to colon carcinomas using MAb EC3. Micrographs of several representative stained sections are shown. Panels A–E corresponded to tumours considered positive only in the stroma; panel F, just in the tumour, and panels G–P; in both compartments. The arrow in panel H labels a cell that cannot be clearly classified as tumoral or stromal. In panel O the arrow points at a cell entering a vessel. Bars indicate magnification.</p

Specific survival of stage I, II and III colon tumour patients according to Snail1 expression in the stroma.

<p>The presence of Snail1 in the stroma of stage I, II and III tumours is represented as continuous lines; dotted lines correspond to stroma-negative tumours. In the lower left panel, expression of Snail1 in the stroma was considered as low or high according to the criteria indicated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005595#s4" target="_blank">Methods</a>. The significance is indicated in each category.</p

Characteristics of 162 patients with colorectal cancer.

<p>Characteristics of 162 patients with colorectal cancer.</p