As people age their faces sag due to changes in skin elasticity (and also often gaining weight), this can lead to a “resting sad face” compared with perky youngsters. But, as a middle aged person, I’ve also started to notice that I often get absorbed in my thoughts and realise I’m sitting there with a thousand yard stare and a drawn facial expression I associate with being sad or very sick or very hungover.

But inside I’m not sad, I’m just thinking about something I need to do or whatever, but I feel like I need to consciously “inhabit” my body again and “power up” my facial muscles so I look thoughtful, or determined or something rather than a blank “my family has just died in a car crash and I can’t decide whether to call the ambulance or kill myself with a shard of broken windscreen” expression.