Religious beliefs, or a sense of spirituality, may cushion some people's brains against depression, according to new research.

A study has found a curious link between our personally held beliefs and the thickness of white matter in our noggins.

The idea is still very much in its infancy, but as findings like these begin to pile up, the link between depression and religion is becoming ever more intriguing.

Today, we know that depression is, at least to some extent, a consequence of our genes. There is quite a bit of research to suggest that if one or both parents are depressed, it can increase a child's risk of depression by double, maybe even quadruple the average amount.

But while these studies strongly suggest a genetic component, depression doesn't affect everyone with a depressed parent, and can also show up in people without any family history whatsoever.

This means there have to be some other factors at play, and a person's intrinsic worldview may be one of them.

Among adults with a high family risk for depression, a firm belief in religion or spirituality - never mind attendance at church or other pious acts - seemed to have a protective effect, shielding some patients from a recurrence of major depressive disorder (MDD).

The research is buttressed by a 2005 study, which found that religion served as a buffer against depression in those with poor health. Plus, a 2013 study found that those who are treated for mental health issues respond better to treatment if they believe in God.

Diving deeper, the new research used a type of MRI-based neuroimaging, called diffusion tensor imaging, to visualise the white matter in the brains of 99 participants, with varying levels of familial risk for depression.

White matter is the pale tissue that makes up the brain's cortex, and it contains the circuitry that brain cells need to communicate with each other.

Previous research has shown that thinning white matter is a biomarker for depression in the brain, and a 2014 study found that religion and spirituality is associated with thicker cortices in several brain regions linked to depression.

The findings of the new study simply feed these correlations. The researchers discovered that those with high familial risk of depression and with important religious or spiritual beliefs, had brains that more closely resembled participants with low familial risk of depression.

"We found that belief in the importance of [religion or spirituality] was associated with thicker cortices in bilateral parietal and occipital regions," the authors conclude.

"As we had previously reported cortical thinning in these regions as a stable biomarker for depression risk, we hypothesised that the thicker cortices in those reporting high importance of [religious or spiritual] beliefs may serve as a compensatory or protective mechanism."

As interesting as these connections are, for the time being, that's all they can be. Until we can say for sure the effect that religion has on white matter, let alone depression, this study and numerous others will need to be replicated, validated and stretched across greater time spans.

When it comes to the human brain, there's no simple answer.

This study has been published in Brain and Behaviour.