Ask the Neuroscientist – an interview with Dr. Nicolas Escoffier

How can neuroscience help to answer questions about our living environment and to understand more about our relationship with our surroundings, above all, nature?

Neuroscience allows to peer inside the brain to study the effect our environment has on us. Of course, there are other, more traditional approaches to investigate these effects, but they have their drawbacks. Such an approach is directly asking people about how they feel while in nature. This has limitations however, because nature might have positive effects we are not conscious of, and that we wouldn’t be able to report. For instance, a recent study has showed that the exposure to nature decreases stress to a greater degree than people expect or realise. Using neuroscience to look at the brain is helpful here because it lets us bypass individual awareness to examine the direct physiological effects. This can highlight positive effect that people do not realise are there. Furthermore, it allows us to understand how the physiological effects lead to reduced stress or enhanced feeling of wellbeing, by looking are which brain regions and brain functions are the most affected by the environment.

Can neuroscience really help measure emotions that people have towards some stimuli, or also other things?

It is possible to use neuroscience tools to measure emotional responses to outside events and environments. There are many ways to approach emotions, the most straightforward is to look at how intense an emotional reaction is, and whether its tone is positive or negative. Neuroscience methods and electroencephalography (EEG) in particular have been used successfully to detect the intensity of a felt emotion. Researchers measure emotional arousal, which reflects how intense the physiological and cortical reactions to an emotional event is. Some studies have reported measuring emotional tone using neuroscience tools, but this is much more challenging and might not be always reliable. This is an instance where asking people to report their emotions would help to increase the confidence in the measurement.

Why, in our opinion, the issue of mental health is gaining so much more importance in the recent years?

You would have to ask a mental health professional for a more informed opinion, I’ll just share mine here. For a long time, there has been many barriers to addressing mental health issues. Until recently, health professionals had very few tools to tackle mental health issues. When new mental health therapies became available, people were not aware of what mental health was, and didn’t know that the issues they experienced could be addressed. Also, there was traditionally a stigma attached to mental health, and people were reticent to seek help because they risked suffering a social stigma and being labelled as “crazy”. As a consequence, it was unclear how widespread mental health issues were in the general population because few people were seeking help. With increasing awareness of these issues, and greater scrutiny of their personal and economic impact, there has been an increasing focus on addressing mental health. There is still a need to develop novel mental health tools however, and the focus has been on health interventions that are efficient and cost-effective.

Research is a big aspect of our work here at NeuroLandscape and it has its challenges. For instance, the fact that each person is different, we have different personalities, system of beliefs and we perceive the world in different ways. How can we be sure that we can extrapolate the results from experiment to all generation if we examined only say 30 participants?

This is one of the greatest challenges in research. Different people will respond in many different ways to their environment, whether in the lab or in the real world. As a first step, research can only examine how a group of people on average respond. While it is possible to get an idea for that general trend, there is also great individual variability associated with it. An important step in the research is then to evaluate that variability, and to make sure that we examine a big enough group of participants. As the group size increases, individual variability has a reduced impact, and a better estimate of the typical response can be reached.
As a second step these differences can be of interest of course. Different groups of people might respond differently based on their background or personality, and it can be interesting to examine how these different backgrounds shape their response. In health, this paves the way for personalised interventions that use the most efficient therapy for a person of a given background.

Going more into detail in research, which equipment is the best to measure passive exposure to landscapes? What are the main limitations?
- fMRI (Functional Magnetic Resonance Imaging)
- EEG (Electrophotography)
- PET (Positron-emission tomography)
- ERP (Event-related potential) 

Briefly, to assess the effect of exposure to real landscape you need to be able to record in the field. This excludes techniques such as fMRI or PET that involve equipment that can only be installed indoors. The best choice for such settings are techniques that are portable such as EEG, and ERP measures. These are recorded with the same equipment, and they involve measuring brain response using electrodes placed on the scalp. If you are not interested in recording brain response in the field, but instead you are interested in examining the response to images of landscape, all these techniques can be used. This is because this can be done indoors using images projected on a screen or in virtual reality goggles for instance.
All these techniques then have their own advantages and drawback. For instance, fMRI and PET, can record the whole brain in high resolution, which allow to localise responses in the brain with high spatial accuracy, typically down to a few millimeters. They are very slow however and can only make a measure every 2 second at their fastest. This makes it almost impossible to examine the precise shape and timing of brain response. In addition, the equipment for these techniques is more expensive and so is running an experiment. On the other hand, the equipment used for EEG, and ERP can record responses every few milliseconds, making it easier to examine the brain response timing and shape. They can, however, only record responses at the scalp, so the localization of the responses is very coarse. For instance, you would only be able to tell whether a response originated from the front, centre, or back of the brain, and from the left or the right side. Furthermore, these techniques cannot record the response of neurons that are located deep in the brain, such as those that process emotions. All these neuroimaging techniques have further trade-offs, and they must be selected with great care based on the goals, the setting, and the budget.

What do you need to be careful with the most when designing the neuroscience experiment and when interpreting the results of neuroscience experiments? Are they really exciting as they seem?

Neuroscience experiments have increased our understanding of how the brain works to a great extent. We can now study how brain functioning can predict better health and well-being. Despite the benefit they bring, they are challenging to conduct, and many aspects must be taken care of to ensure that the results follow gold standards. Experiments that do not follow these standards will lead to outcomes that don’t accurately represent what’s happening in the real world. There are many features to take care of, but let me focus on two main ones here. 

First, it is important to verify that the experiment is designed to really answer the questions one wants to examine. Sometimes an experiment will compare the difference between two groups, for example between people who exercise and people who don’t, and find a difference in health outcomes. But it is important to check than no other difference between the groups can explain the results. For instance, if the groups that exercise turns out to be younger in age, then the health benefits might be due to their younger age, and exercising might not help at all. Of course, we know that exercise enhances health, but we only know that because prior studies ensured that results were not influenced by other parameters such as age. Researchers guaranteed that by testing people from the same age group for instance.

A second important aspect is to make sure that a large enough group of participants is tested. This matters because the larger the group, the more likely the results will apply to everyone. Imagine an extreme case where you would only test two people. For instance, you test someone who exercises regularly, but who has other issues that deteriorate his or her health, with someone who does not exercise but has been gifted with good health. Based on these two people, you would conclude exercising deteriorates health! This conclusion would be based on random occurrences, and would not reflect the real world. To avoid these issues, studies must have a high enough number of participants whose results are averaged together. This guarantees that random occurrences have only a small influence on the results, and that the study outcome is close to what can be found in the whole of the general population. These are just two of many other aspects that are important to consider.

How would you assess the depth of the current knowledge about the human brain? Is it a field that is well-examined, or rather in its infancy? Where do you see neuroscience going in the future?

I would say we have made great progress in the past 50 years, with more advanced techniques available to understand the basic mechanisms involved in the information processing the brain does. There is still so much ahead of us because the brain is incredibly complex. No one knows what the future will look like, but more recent advances have brought new insights by examining how the various brain regions, and the neurons in them, communicate and connect to form networks. The research suggests that these networks undergird the brain functions, and the future will likely see an increased focus on understanding how these networks store information, how they interact, and how changes in their integrity explain changes in behaviour and health and wellbeing.

And how do you personally look after your mental health, given your knowledge of the brain, and what advice do you have for the average person?

I personally like to spend time in nature, in conversations with friends, and reading, meditating and practicing martial arts.  And of course, if I had any issue I couldn’t cope with I would seek the help of a mental health professional. If you were to only do one thing to take care of your brain in daily life, it should probably be physical exercise. It’s great for mood and stimulates neural cell growth and helps with memory and cognition. Beyond that, any cognitively challenging activity will work to train your brain functions, such as taking up a new hobby, or having an interesting and intellectually-engaging work. It is also better if these activities are social and involve contact and exchange with other people. In addition, research indicates that activities that train awareness such as mindfulness practices are also good. Finally, mounting evidence suggests that exposure to nature is beneficial, so it might be even better when all these activities are performed outdoors in green environments.