Biophilic Interventions in Space Habitat Crew Quarters to Improve Cognitive & Physiological Health

Abstract

Biophilia is the innate love of life and utilizing this concept when designing interior environments is known as Biophilic Design. Natural materials, biomorphic forms, and the incorporation of plants and green elements are all strategies to implement biophilic design. Biophilic design can improve the cognitive and physiological health of individuals in interior environments. The purpose of this study was to assess if the integration of biophilic design in a virtual simulation of crew quarters on the International Space Station (ISS) can help improve emotions, while also improving cognitive and physiological responses in individuals. The research questions include: 1. How does the environment affect feelings experienced (calm, content, nervous, and indecisive)?, 2. How does the environment affect cognitive load (pupil dilation)?, 3. How do emotions experienced in the environment (calm, content, nervous, and indecisive) affect satisfaction and intention to spend more time in the environment?, 4. How does cognitive load (pupil dilation) affect cognitive responses including task completion time, memory retention, and visuo-spatial processing? There were 40 participants in the study (age 18–57 with a median age of 25.5 years; gender - 10 male, 19 female, and 1 non-binary). The participants responded to survey questions to assess specific measures including emotions, task load, and cognition when they experienced two different virtual reality environments: a) existing crew quarters, and b) proposed biophilic crew quarters. In addition, heart rate and pupil dilation were also measured to assess physiological and cognitive responses respectively. A paired t-test and Pearson correlation was used for the statistical analysis, with the significance level set at 0.05. The study found that there were statistically significant differences for emotions, including feelings of calm $(\mathrm{p} < 0.0001)$, content $(\mathrm{p} < 0.0001)$, nervousness $(\mathrm{p} < 0.0001)$ and indecisiveness $(\mathrm{p} < 0.0001)$, across the two environments. These measures showed weak correlation $(\mathrm{r}^{2} < 0.30)$ to heart rate. However, there was a moderate correlation between nervousness $(\mathrm{r}^{2}=-0.51)$ and indecisiveness $(\mathrm{r}^{2}=-0.57)$, and strong correlation between calm $(\mathrm{r}^{2}=0.68)$ and content $(\mathrm{r}^{2} =0.72)$ to intention to spend more time in the space. For the measure satisfaction within the space, there was a moderate correlation with nervousness $(\mathrm{r}^{2}=-0.47)$ and indecisiveness $(\mathrm{r}^{2}= -0.50)$, and a strong correlation with calm $(\mathrm{r}^{2}=0.77)$ and content $(\mathrm{r}^{2}=0.78)$. There was also a statistically significant difference for pupil dilation $(\mathrm{p}=0.0001)$ across the two environments. However, there was a weak correlation between pupil dilation and both task load $(\mathrm{r}^{2} < 0.10)$ and cognitive responses $(\mathrm{r}^{2} < 0.15)$. This study provides unique research for the design of crew quarters as previous short-term space habitats have been designed primarily for efficiency and safety, and less focused on the occupant's physiological and cognitive health. Biophilic design could be beneficial for creating spaces that act as a human health countermeasure and to help ensure the wellbeing of astronauts and space travelers.