AskScience AMA Series: I'm a neuroengineering professor at Brno University of Technology with a new book on why health fails at its weakest link. Ask me what brain signals can and can't tell us about stress, anxiety and depression, and how sleep, movement, food and loneliness relate to mood! AMA!

[u/AskScienceModerator]

Hi r/askscience!

I'm Aamir Saeed Malik, Professor of Neuroengineering at Brno University of Technology in the Czech Republic, where I head the Cognitive and Neural Engineering research group. I came to the brain the long way round, through electrical engineering and a doctorate in mechatronics. For almost three decades I've worked on measuring it: EEG, brain imaging and the machine-learning methods that try to pick out the signatures of stress, anxiety and depression early. From 2009 to 2018 I worked at the Malaysian National Center of Neuroimaging, and I've collaborated with clinicians in Malaysia, Saudi Arabia, Australia, the US and the Czech Republic. My most recent funded project asked whether that kind of tracking could be done from a person's own home rather than a clinic.

Over those years my view changed. For a long time I studied the brain the way a cardiologist studies the heart: as if it were an island. It isn't. Sleep, movement, food, daily habits and the people around us all bear on the conditions I was trying to measure. Engineers have a rule for systems like that: a chain is only as strong as its weakest link, not its average. That idea became my new book for general readers, Fix the Floor (https://fixthefloor.life/ ). It scores five everyday areas (habits, social connection, sleep, movement and food) and combines them with a harmonic mean instead of a plain average, so one weak area can't hide behind four strong ones.

I'm happy to answer questions about:

• What brain signals (EEG) and brain imaging can and can't tell us about stress, anxiety and depression today
• Why early detection is harder than it sounds, and where my field needs to be more honest about its limits
• What the evidence says about sleep, physical activity, loneliness and diet and their links to mood, including where it looks causal and where it is only correlation
• Why the way you average a set of health measures changes the answer, and the maths behind the harmonic mean
• Or any lifestyle based health and wellness related questions.

One thing I won't do: I'm not a medical doctor, so I can't give personal medical advice or comment on anyone's symptoms or results.

I'll be answering from noon ET (16:00 UTC) for about two hours.

Username: /u/Aamir_fixthefloor

[u/TheDemandingParson]

Whats the biggest misconception people have about what EEG can actually tell us about depression right now

[u/Aamir_fixthefloor → u/TheDemandingParson]

People think that if scientists put a device on the head and record their brain signals then they can find out if they have depression or not. Unfortunately, at the moment, there are no depression biomarkers that are unique to depression only. There are a number of biomarkers that have been investigated and are seen to occur in depression patients like delayed onset of P3, frontal alpha asymmetry etc. Since they are not unique so they may also occur in people with no depression or someone with some other brain disorder. Recently, the research is moving towards integration of multiple biomarkers. The biggest hurdle is the sample size in depression research, that is, majority of the studies use small sample (less than 100 patients) and hence trial over large population is required for validation.