What example was given of the speaker's father losing a practical ability despite having been a highly skilled surgeon?

What new activity did the speaker say she had tried in order to challenge her brain?

What phrase from Dr Tommy Wood's work was mentioned as a way of describing the need to struggle with new activities?

During the consultation-style section, what did the volunteer identify as one of her regular emotions on a normal day?

What "curfew" did the speaker suggest as a way of reducing night-time stress?