Most of us know what it takes to maintain our physical health, but what does it mean to have a healthy brain?

Professor Hanneke Hulst, a neuroscientist and director of the Centre for Brain Research at the University of Auckland, says brain health depends on multiple factors.

“It is physical health, but it’s also our environment, our opportunities to learn, social connection, safety, access to good healthcare, and I think all of these influence how our brains develop, adapt, respond to challenges throughout life,” she says.

Hulst’s research focuses on cognitive impairment in multiple sclerosis and its effects on those who live with the condition. But she says it’s important to think and talk about brain health not only in the context of disease, but in everyday life.

“We all want to flourish, whether in the presence or absence of a diagnosis,” she says.

Here she shares questions people ask her about brain health and what we can do to look after it.

Why do we feel mentally drained after a long day – and what can we do about it?

You might think if you’re not doing physical work all day, you shouldn’t feel tired – but making decisions, switching between tasks and managing your emotions all require sustained mental effort, Hulst says.

“We are constantly triggered by our emails, [by our] phones, by meetings, by messages, by conversations ... often we are not giving our brains much opportunity to rest.”