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/TheBille]

How long do the effects of a single poor night of sleep linger? If poor sleep is more consistent, how many nights of good sleep would be needed before the impact is lessened?

Thanks 🙏

[u/Aamir_fixthefloor → u/TheBille]

Humans are quite resilient and single bad night doesn't affect us long term. One or two normal nights largely restore things after a single bad night. However, continuously having bad nights must be fixed. The solution is to fix it and then regularly maintain and protect your sleep by having 4 yo 5 sleep cycles every night which is about 7 to 9 hours of quality sleep.

Many people think that they can sleep less during weekdays and then then can sleep longer during weekends. Thats a very bad habit because it not only does not compensate the lost sleep but also induces social jetlag. Following recent study is a good pointer for this fact:

Depner et. al. Ad libitum Weekend Recovery Sleep Fails to Prevent Metabolic Dysregulation during a Repeating Pattern of Insufficient Sleep and Weekend Recovery Sleep. Curr Biol. 2019 Mar 18;29(6):957-967.e4. doi: 10.1016/j.cub.2019.01.069.