The study, led by Yusuke Nagamori of Tokyo City University and colleagues at Ritsumeikan University and Tohoku University, focused on a trait called Visualization, measured with the Visualization subscale of the design attitude measure, a fifteen-item self-report questionnaire spanning five dimensions including Experimentalism, Optimism, Collaboration, and Empathy. Visualization captures a preference for externalizing ideas through visual representation, and it is the only dimension previously reported to distinguish design professionals from other white-collar workers. Crucially, the researchers treated Visualization not as a synonym for holding a designer job title but as a continuous disposition that varies within the general population, and they statistically adjusted for occupation in their key models to see whether the disposition itself carried information beyond the label.

Thirty-nine working adults, nineteen professional designers and twenty non-designers drawn from administration, sales, and non-design engineering, completed an open-ended block-building task in which they constructed chairs from physical blocks. Each participant did this twice, once with a constrained kit of forty-five monochromatic cool-gray interlocking blocks and once with a broad kit of ninety multicolored pastel blocks offering more pieces, more colors, and a different shape distribution. Because the task was self-paced, trial durations ranged from roughly two to nearly nineteen minutes, and no clock was visible. The researchers deliberately avoided the artificial, tightly timed paradigms typical of laboratory creativity research, embracing the ecological validity that defines the neuroergonomics tradition.

Brain activity was recorded with a wearable two-channel functional near-infrared spectroscopy device, the NeU HOT-2000, positioned over the Fp1 and Fp2 sites of the forehead in the standard 10-20 electroencephalography system. The device sampled at 10 hertz using a single near-isosbestic wavelength of 810 nanometers, which means it yields a relative total-hemoglobin signal rather than separate oxy- and deoxyhemoglobin concentrations. To reduce contamination from superficial scalp blood flow, the team applied short-separation regression, regressing the signal from 1-centimeter channels out of the 3-centimeter channels, a step that removed a median of 74 to 80 percent of the long-channel variance. The authors are careful to interpret their measure as a relative prefrontal hemodynamic index, not as direct evidence of cortical activation at specific anatomical locations.

The first finding confirmed expectations: designers scored significantly higher than non-designers on Visualization, with a large effect size of d = 1.07, while none of the other four design attitude dimensions differed between the groups after statistical correction. This validated the known-groups property of the scale and set the stage for the central question, which was tested with ordinary least squares regression on the difference in prefrontal signal between the broad and constrained material conditions.

That central result is where the study becomes genuinely novel. After adjusting for occupation, higher Visualization scores were associated with a larger difference in the Fp2 signal between the broad and constrained sets. The interaction between material condition and Visualization was statistically significant, and a time-resolved analysis localized it to a single window spanning roughly 60 to 79 percent of each participant’s normalized design timeline, with a cluster-corrected p-value of 0.013. Within that window, the effect survived all thirty-nine leave-one-out refits, meaning no single participant drove the result. The positive simple slope was present only under the broad material set; under the constrained monochromatic set, higher Visualization carried no detectable relationship with the prefrontal signal at all.

Beneath this pattern lies a statistical subtlety the authors highlight as substantively interesting rather than a nuisance. Visualization and occupation were positively correlated, yet their partial associations with the material-context sensitivity of the Fp2 signal ran in opposite directions: at a given level of Visualization, being a designer was actually associated with a smaller broad-versus-constrained difference, while the disposition itself predicted a larger one. Adjusting for occupation therefore increased the Visualization coefficient from +0.11 to +0.19, a textbook case of statistical suppression. In plain terms, the dispositional preference for visual externalization carried information about the prefrontal signal that the occupational label partly masked, supporting the study’s premise that design attitude is a continuous trait rather than a proxy for a job category.

The participants’ subjective experiences reinforced the material-context story. The broad, colorful set was rated as less difficult, more enjoyable, and more conducive to idea generation than the constrained gray set, though perceived material sufficiency did not differ. The authors caution that the two kits differed simultaneously in color, piece count, and shape distribution, so material variety is a composite variable, and a future factorial manipulation would be needed to isolate which attribute matters. Notably, however, a sensitivity model including the four subjective-rating differences still yielded a positive interaction, suggesting that the experiential differences alone do not explain the hemodynamic result.

The team also employed a clever analytical innovation suited to unstructured real-world tasks: proportional-time normalization. Because participants took wildly different amounts of time, their recordings could not be aligned on an absolute clock, so each trial was resampled onto a common 100-point grid from onset to completion. Combining this with cluster-based permutation testing allowed the researchers to localize the Visualization-related effect along an otherwise unsegmented, self-paced process without imposing predefined stages. They speculate that the mid-to-late window may correspond to a shift from generating ideas toward evaluating and refining them, but they present this only as a hypothesis for confirmatory work with behavioral phase markers.

The researchers are appropriately measured about their conclusions. The whole-design estimate was sensitive to one influential participant and to conservative small-sample standard errors, the two-site montage cannot resolve specific prefrontal regions or fully separate cortical from systemic signals, and the brief three-item Visualization subscale has only moderate reliability. No reliable right-hemisphere lateralization was established, since the formal comparison between Fp2 and Fp1 did not reach significance. Still, the findings point toward something practically important: in field applications of wearable fNIRS, from workload monitoring to workspace evaluation, the person and the context may need to be modeled jointly rather than interpreted in isolation. De-identified data are openly available, and the authors explicitly call for a preregistered replication, a fittingly rigorous coda for a study that brings brain measurement one step closer to the messy, creative reality of design work.

Subject of Research: The relationship between a design-related Visualization disposition and prefrontal hemodynamics during naturalistic block-building design, measured with wearable fNIRS.

Article Title: Material context moderates the occupation-adjusted association between Visualization and prefrontal hemodynamics during naturalistic design: an exploratory wearable fNIRS study

Article References: Nagamori, Y., Suzuki, F., Isobe, M., Miyoshi, H., Shikata, T., Ando, T., & Yaegashi, K. (2026). Material context moderates the occupation-adjusted association between Visualization and prefrontal hemodynamics during naturalistic design: an exploratory wearable fNIRS study. Frontiers in Neuroergonomics, 7, Article 1928775. https://doi.org/10.3389/fnrgo.2026.1928775

Image Credits: AI Generated

DOI: 10.3389/fnrgo.2026.1928775

Keywords: wearable fNIRS, neuroergonomics, prefrontal cortex, design attitude, visualization, naturalistic design, creative cognition, proportional-time normalization, statistical suppression, material context, individual differences, total hemoglobin