Impact of biophilic design on college student perception of mental health and environmental benefits: A dose-response study

 To exam the dose-response effect, a total of 101 plants were placed incrementally in the BC. The first 50 plants were placed in Week 4 and 51 more plants were added in Week 10. All plants were removed during Week 14.

 To understand if the results of having plants was linked to their quantity, the researchers added 50 plants to the BC (the classroom of the intervention, BC meaning biophilic classroom) in the forth week of the study. After 6 weeks, so in week 10, they added another 51 plants to the same room. The room had now 101 plants. All of those were taken away by week 14. 

 University years are crucial for developing health in general, yet college students increasingly report mental health issues (e.g., stresses, short attention span) and reduced 2 Assignment 1: Environmental Effects on Mental Health Worksheet cognitive performance [10,11]. Indoor classroom environments, often disconnected from nature, can exacerbate these issues, may potentially impaire students’ well-being and academic performance [12]. 

Although students experiment an improvement on their general health during their college years, they also report more and more mental health and cognitive struggling. Because classrooms are places that don’t have much of nature and plants, being there can make this struggling worse to a point that could affect student’s grades and learning. 

The results show that students in the BC group, but not in the CC group, perceived indoor environmental air quality, air freshness, and productivity to be higher at T2 and T3 compared to T1. When the plants were removed at T4, these levels returned to baseline. 

When researchers compared how students felt regarding the classroom air quality air freshness, and their own productivity on the subsequent surveys (T1 being before adding plants, at the end of week 3, T2 being at the end of week 7, T3 being at the end of week 12, and T4, 4 weeks after removing the plants), all parameters were better on T2 and T3 than on T1. The same perception of T1 was seen at T4. 

The findings indicate that plant placement in the classroom increased student perceived indoor environmental quality, air freshness, and productivity. This suggests adding a “dose” of plants, that is, going from 0 plants to 50 plants was effective but increasing the dose (i.e., 50–101 plants) did not further improve students’ perceptions, possibly due to a “ceiling effect” related to the number of plants within a room of a certain size. 

The researchers concluded that adding plants to the classroom had positive effect on how students felt the environment quality, air freshness, and their productivity (being able to pay attention to lectures, take notes, and retain what they’ve learnt in class). The same effect was not maximized when the number of plants was increased. They suggest that this was due to what they call “ceiling effect”, what we can understand as a maximum stimulus where any increment will not reflect in further improvement on the results. 

The authors suggested that new studies could be conducted to evaluate possible long-term effects of Biophilic classrooms on student’s learning and well-being perception, as well as what different biophilic designs could contribute on this matter. 

In my opinion, further studies should try to measure well-being outcomes using psychological tools instead of “perception” as this study did. They’ve used quantitative methods for the air quality measurement, but they were more vague on the mental aspect. 

The most challenge aspect for me was to understand the statistical methods they used in the research. I was not familiarized to them at all, and it took me quite a few re-readings to make the connections between their numbers and results. I feel that a basic statistics course could resolve this matter.