I agree, though I feel its a potentially unintuitive way of saying it in a pop-sci journal targeted at the general public. If you tell most people that high temperatures makes their body produce excessive "Hypothalamic-Pituitary-Adrenal," they won't have a great frame of reference for what you mean, and how that might cause them to feel symptoms of depression.

But you can tell anyone that high temperatures can keep them up at night, and cause them to feel miserable the next day, and I think they'll both fully understand what your saying and probably find it pretty applicable to their own experiences. I fully understand the need for scientific terms in professional contexts, but in an article like this good communication means getting things across in clear language that their audience understands.

I don't think so in this instance it probably is saying that the high temperature leads to a mismatch between the 'local circadian time' of a part of the body and the 'master clock' in the brain. Mismatches have proven to exist and to cause chemical imbalance in our body for example eating windows and it's effect on our body in respect to blood sugars. I even wrote about that one a couple of months back on hexbear if it's still there. I could totally see that a mismatch can cause that and doing tests between people with a conditioned vs unconditioned room could be interesting to look at. Also circadian rhythm is still fairly new grounds I think the knowledge that 'local' circadian clocks exist is only about a decade old.