# Correlation Between Co-Design and Psychological Need Satisfaction Based on fNIRs Hyperscanning
## 1 Introduction
Neuroscience is a discipline that studies the impact of the nervous system on behavior and cognition using methods such as functional near-infrared spectroscopy brain imaging fNIRS (functional near-infrared spectroscopy) [13], EEG (electroencephalography) [14], fMRI (functional magnetic resonance imaging) [15], and MEG (magnetoencephalography) [16] to help understand brain functioning. Among them, superscanning technology is widely used as the main method in research on different types of team activities. The concept of superscan was first proposed by [PERSON] in 2002 [17]. This is a technique that can simultaneously collect changes in brain activity from two or more individuals [18]. [PERSON] [19] found that it can not only observe the activity of individual brain regions, but also pay attention to the synchronicity of brain activity among multiple individuals. IBS (inter-brain synchronization) is considered a consistent response observed through neuroscience, meaning that when two or more experimental participants complete a specified task, the correlation between activity signals recorded in relevant brain regions can be considered as the similarity or synchronicity of brain activity. In the context of teamwork, the rise in IBS can be seen as a coordination and synchronization of neural activity among team members. This synchronicity may help team members better understand and share each other's ideas, thereby promoting team creativity. This technology provides support for observing how people receive ideas from others and think about feedback in team tasks. Among them, fNIRS has better tolerance to head movements and non-invasiveness [20], and has been successfully applied in fieldssuch as sports [21] and face-to-face communication [22]. In addition, the research results of fNIRS have laid a theoretical foundation for the psychological theory of team tasks [23], and provided technical support for their psychological cognitive assessment and psychological state observation. Therefore, this technology is considered to have practical value and prospects in the field of team collaboration research. The working principle of fNIRS imaging relies on the absorption law of light in different media; that is, the wavelength of light and the type of medium have an impact on the absorption coefficient of light in the medium. Among them, HbO\({}_{2}\) and Hb are sensitive to near-infrared light with wavelengths of around 760 nm and 850 nm, respectively. Therefore, in the near-infrared ultrascanning experiment, the instrument uses 760 nm and 850 nm types of light as the emitting light sources. Light passes through the scalp and skull, and is ultimately absorbed by HbO\({}_{2}\) and Hb in the cerebral cortex capillary blood. Calculate the changes in local HbO\({}_{2}\) and Hb concentrations by using BLL (Beer-Lambert Law). This law is a fundamental principle of light absorption and applies to all forms of electromagnetic radiation as well as all light-absorbing substances, including gases, solids, liquids, molecules, atoms, and ions. It states that when a beam of monochromatic light passes through a uniform absorbing medium, the intensity of the light decreases exponentially with both the thickness of the medium and the concentration of the absorbing substance. The basic theory of fNIRS imaging is the neurovascular coupling mechanism [24], which states that there is a relationship between local neural activation and changes in cerebral blood flow, and the cerebral blood flow supply responds locally to changes in functional activity. After stimulation, the cerebral cortex consumes HbO\({}_{2}\), leading to an increase in Hb concentration. Subsequently, the compensatory effect of cerebral blood flow causes capillaries to dilate and flow into fresh blood, resulting in an increase in HbO\({}_{2}\) concentration and a decrease in Hb concentration. This process is consistent with the HRF (hemodynamic response function) [25].