Adrenarche – that other puberty

Most of us are familiar with a stage of puberty (that we probably hope we can forever push to the back of our minds and never re-live ever again, and desperately hope that when our own children reach that stage, that our partner will take over parenting duties for a few years…) called gonadarche. This is the more obvious phase of puberty where secondary sex characteristics appear and hormones that are released from the gonads (testosterone for boys, estradiol for girls) start to increase. For girls, these are responsible for the start of menstruation. Chronological ages for the start of this phase vary a lot (and interestingly, for girls, where the start of menstruation is an easy way to mark this onset, ages have been getting increasingly younger over the past century!), but most would place this in the beginning of the teenage years.

What a lot of people don’t know is that there another, earlier phase of puberty that everyone goes through, when hormones from the adrenal gland such as DHEA are released, that is aptly named adrenarche. Again, ages vary, but we think kids around 6-10 (maybe as early as 5!) are going through this development. There are some physical changes that go along with with this phase of puberty too, like an increase in body and pubic hair.

My colleagues and I are especially interested in this phase of puberty, partly because we know less about it than gonadarche, but also because there is some evidence to suggest that the timing of it (i.e., when kids go through this phase compared to their same sex and chronological aged peers) is associated with mental health problems. We also think  that this might be due to important changes in brain development during this time of life, but we need more research to test this. The bottom line is that we need to better understand this phase of life for kids because it could have really important implications for their brain and mental health later in life.sagittal_brain_mri

We’ve written a review paper that systematically goes through all the literature on adrenarche, mental health, and brain development. Then we propose a model for future research to test if adrenarche is a particularly sensitive time of neurobiological and mental health development for kids. It’s just been published in the excellent journal* Developmental Cognitive Neuroscience. It is an open access journal, meaning that anyone can see the full text (BIG CHEERS FOR THAT!). I hope you enjoy reading it.

*Also be on the lookout for a special issue in DCN coming out later this year, on methodological challenges in developmental neuroimaging, that I am helping to guest edit.

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5 thoughts on “Adrenarche – that other puberty

  1. Dan says:

    An interesting read. Following the recent passing of a friend, I would be interested in neurobiology of phase of the grieving process.

    • I’m so sorry for your loss. It is a good question and an area I am not totally familiar with. But there is one very interesting study that looks at the neurobiology and levels of inflammation in bereaved women that is a very important piece of work because it highlights the link between the inflammatory (stress) response and activation in emotional parts of the brain in the ventral prefrontal area. In depression research we are interested in brain networks that seem to be influenced by inflammation and are implicated in mood disorders such as depression – so it is interesting to see this work extend to bereavement, as well. Grief can be a very stressful experience for many people that has an effect on not just acute but sometime chronic inflammatory processes – with flow-on effects to physical inflammatory diseases such as heart disease. I recommend the paper, and let me know if you can’t get access to it (although it should be publically available here).

      O’Connor, M-F, et al. (2009). When grief heats up: Pro-inflammatory cytokines predict regional brain activation. NeuroImage, 47:891–896

      • Dan says:

        Thank you.

        Acceleration of the inflammation process by the neurochemicals released during various stages of grief has been patent obvious for me, as my symptoms of chronic pelvic pain have ratcheted up substantially this past week. So much so I opted for yet another testicular ultrasound and then an MRI. All due to disconcerting changes in my apparent level of continuing discomfort and the amount of swelling.
        Get MRI results on Monday to rule out anything sinister, so I can then consider a management plan forchronic pain.

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