This is way more complicated than it should be, compared to the easy option of a quick flight :(
Thinking hard for several hours can leave us feeling mentally tired – and now we may know why. Prolonged concentration leads to the build-up of a compound called glutamate in regions at the front of the brain. This may provide an explanation as to why we avoid difficult tasks when mentally fatigued: the glutamate overload makes further mental work difficult. Too much glutamate is potentially harmful, says Antonius Wiehler at the Paris Brain Institute in France, who led the research. “The brain wants to avoid this, so it is trying to reduce activity.” Many of us have experienced mental weariness after a hard day of thinking, but until now, we didn’t know why. The brain doesn’t seem to run out of energy after working hard and even when we aren’t deliberately thinking about anything specific, some brain regions, called the “default mode network”, are as active as ever. To learn more, Wiehler and his team used a technique called magnetic resonance spectroscopy (MRS), which measures levels of various chemicals in living tissue harmlessly. They focused on a region towards the front and sides of the brain called the lateral prefrontal cortex […] Levels of eight different brain chemicals were measured, including glutamate, which is the main signalling chemical between neurons. After completing the memory tasks for 6 hours, those doing the harder version had raised levels of glutamate in their lateral prefrontal cortex compared with the start of the experiment. In those doing the easier task, levels stayed about the same. Across all participants, there was no rise in the other seven brain chemicals that were measured. Among the participants doing the harder tasks, their glutamate level rise tallied with dilation of the pupils in their eyes, another broad measure of fatigue. Those doing the simpler task reported feeling tired, but had no glutamate rise or pupil dilation.
Data from more than a dozen studies of more than 30,000 transgender and gender-diverse young people consistently show that access to gender-affirming care is associated with better mental health outcomes—and that lack of access to such care is associated with higher rates of suicidality, depression and self-harming behavior. (Gender diversity refers to the extent to which a person’s gendered behaviors, appearance and identities are culturally incongruent with the sex they were assigned at birth. Gender-diverse people can identify along the transgender spectrum, but not all do.) Major medical organizations, including the American Academy of Pediatrics (AAP), the American Academy of Child and Adolescent Psychiatry, the Endocrine Society, the American Medical Association, the American Psychological Association and the American Psychiatric Association, have published policy statements and guidelines on how to provide age-appropriate gender-affirming care. All of those medical societies find such care to be evidence-based and medically necessary.