The Vielight Neuro Gamma was utilized in a study examining the link between creativity and brain photobiomodulation, specifically of the Default Mode Network.

This groundbreaking study had 58 healthy participants and was sham-controlled, single-blinded and randomized. Researchers from the University of Deusto, Spain, the University of Montpellier, France and Pennsylvania State University, USA were involved in this study.

The Vielight Neuro Gamma was chosen for this study because it concentrates 810nm NIR light energy into the brain’s Default Mode Network at a transcranial surface power density of 100 mW/cm2 and an intranasal power density of 25 mW/cm2, pulsed at 40Hz.

Full study here: Link

Dynamic Subcortical Modulators of Human Default Mode Network Function, Ben J. Harrison, Christopher G. Davey, Hannah S. Savage, bioRxiv 2021.10.27.466172

Creativity and the Default Mode Network

The Default Mode Network (DMN) has been identified as a key neural network associated with creativity.

Studies exploring the relationship between the DMN and creativity have yielded compelling results. One study conducted by Beaty and colleagues (2014) used functional magnetic resonance imaging (fMRI) to investigate brain activity during creative idea generation. They found that individuals who exhibited stronger connectivity within the DMN produced more original and innovative ideas.

Another study by Ellamil et al. (2012) explored the role of the DMN in creativity by examining brain activity during a creative thinking task. The researchers discovered that during idea generation, the DMN was more active, suggesting its involvement in facilitating the creative process.

Material and Methods

Participants

58 healthy volunteers, above 18 years old, were recruited from the general population (mainly from the university but also from the general population through social media advertising).

The study obtained the ethical approval from the Research Ethics Committee.

Design and Procedure

This study consisted of a single session.

The participants were randomly assigned to one of the two groups (n = 29 in each group):

  • Real brain PBM with the Vielight Neuro Gamma
  • Sham

Results suggest that participants were not able to guess between real and sham conditions [χ2 (1, N = 57) = 3.69, p = .158].

At the start, participants had:

  • 2 min 45 s to complete the Remote Associates Test (RAT)
  • 2 min for Unusual Uses (UU) and Picture Completion (PC) subtests

After 20 min of  brain PBM with the Vielight Neuro Gamma, the participants completed:

  • Parallel versions of RAT, UU and PC in a counterbalanced order.

Figure 1. Study design

What are the RAT, UU and PC tests?

The RAT, UU and PC tests are part of the The Torrance Tests of Creative Thinking (TTCT). These are a standardized series of assessments designed to measure creativity in individuals.

  • Remote Associates Test (RAT) is a creativity test used to determine a human’s creative potential.
    Each question on the RAT test lists a group of words, and requires that we provide a single extra word that will link all the others together.

Example:
Square / Cardboard / Open – BOX
Broken / Clear / Eye – GLASS
Coin / Quick / Spoon – SILVER
Time / Hair / Stretch – LONG
Aid / Rubber / Wagon – BAND

  • Unusual Uses (UU) – This subtest involves presenting the individual with a common object, and asking them to think of as many unusual uses for that object as possible. It measures the individual’s flexibility of thought, their ability to think divergently, and to see beyond conventional uses or constraints.
  • Picture Completion (PC) – For this subtest, the examinee is given several incomplete pictures or cues, and they are asked to complete these in the most imaginative way possible.

Divergent Thinking (DT) and Convergent Thinking (CT) Scores

For this creativity and brain photobiomodulation study:

  • DT composite score was created based on fluency, originality, and flexibility scores from UU and PC.
  • CT score was based on the RAT test.

Results

Baseline Characteristics:

At baseline, there were no significant differences observed between the real and sham groups in any of the variables, which included age, sex, years of education, and handedness.

The mean age of the general sample was 28.31 years (standard deviation = 11.21), and the average number of completed years of education was 14.74 (standard deviation = 2.69). Among the general sample, 46.6% were male, and 53.4% were female.

Effects of Neuro Gamma on DT and CT Scores:

The total DT and CT scores at baseline and post-treatment are displayed in Table 2.

ANCOVA results (post-treatment comparisons controlling for baseline scores) are shown in Table 3.

Change score distributions in verbal DT (UU), visual DT (PC), and total DT are shown in Figure 3.

  • The results revealed significant differences between both groups in verbal DT (total UU) with a medium effect size (n²p = 0.10), indicating higher performance after tPBM compared to sham.
  • The visual DT (total PC) score was also significant, suggesting that tPBM produced higher performance than the sham group, demonstrating a large effect size (n²p = 0.14).
  • Lastly, the total DT score was significantly higher after tPBM compared to sham, displaying a large effect size (n²p = 0.24).

Effects of tPBM on DT Subdomains:

  • Regarding verbal DT subdomains, the results suggest that the originality dimension was significantly higher after tPBM compared to sham (see Table 4), indicating a large effect size (n²p = 0.15).
  • The effects on PC showed significant differences in fluency, with a medium effect size (n²p = 0.13).
  • In terms of the percentage of original responses, there was a significantly higher percentage of original responses in UU (F = 5.90, p = .018) after tPBM (Marginal mean = 75.23, Standard Error = 3.73).

Discussion

The study aimed to examine the impact of transcranial photobiomodulation (tPBM) on the default mode network (DMN) in healthy individuals and its effect on creative thinking, specifically divergent thinking (DT), while also exploring the role of anxiety in this relationship. The results supported the hypothesis that tPBM of the DMN improves DT without influencing anxiety levels.

The tPBM treatment significantly enhanced verbal and visual DT, particularly in the dimensions of originality and fluency. These findings align with previous neuroimaging studies linking the DMN to DT. The DMN is associated with cognitive processes like mind wandering and episodic memory, which have been linked to creativity.

However, the relationship between mind wandering and DT is not consistently supported, as negative rumination and mind wandering during idea generation may hinder creativity. Although this study did not assess mind wandering, future research could explore whether tPBM’s effect on DT is partially mediated by mind wandering.

The role of episodic memory in creativity and its connection to the default mode network (DMN) is explored in this passage. The idea generation process in divergent thinking (DT) tasks is suggested to involve the flexible retrieval of specific episodic details. The DMN plays a potential role in this process by facilitating the generation of unique and novel ideas while inhibiting mundane ones.

The study presented in Table 4 compares the effects of transcranial photobiomodulation (tPBM) and sham stimulation on different subdomains of DT. Results indicate that tPBM over the DMN significantly enhances verbal and visual DT, particularly in the dimensions of originality and fluency. The DMN’s involvement in DT is consistent with previous research, although creativity also relies on the synchronization between the DMN and other brain networks such as the executive control network and salience network.

The study did not find a significant effect of tPBM on convergent thinking (CT), which further supports the specific role of the DMN in the idea generation phase of creativity. It is suggested that tPBM may facilitate the transition from mind-wandering (DMN) to focused attention (salience and executive control networks), potentially explaining the improvement in DT tasks. Previous studies on tES and tPBM have demonstrated changes in functional connectivity and power levels in specific brain regions associated with creativity.

The lack of adverse effects and the broader stimulation of the DMN are advantages of tPBM compared to tES. However, limitations of the study include the limited time for DT tasks, the inclusion of compound items in the RAT measure, and the immediate assessment after stimulation. Future research should address these limitations, explore the mediating effects of other cognitive functions, and incorporate neuroimaging techniques to examine the neurophysiological effects of tPBM.

The study’s findings contribute to the growing body of research on tPBM’s cognitive effects and its potential applications in various cognitive and behavioral domains.