New Research On The Aetiology Of Bipolar Disorder.

John D. Pettigrew and Steven M. Miller argue that the underlying pathophysiology for Bipolar Disorder remains elusive, the disorder being strongly heritable but acknowledging that genetics are complicated. Pettigrew and Miller use the term inter-hemispheric switching which looks at trait-dependent biological markers associated with bipolar disorder. Proposing that bipolar disorder is the product of genetic propensity of slow inter-hemispheric switching mechanisms which can become ‘stuck’ in one particular state. Pettigrew and Miller state that slower switches are more ‘sticky’ in contrast to faster switches, hypothesising that the clinical manifestations of bipolar disorder can possibly be explained by hemispheric activation, which could be caught on the right (depression) or the left (mania). The research is based on rates of perceptual alteration in binocular rivalries that appears to be slower in bipolar disorder subjects who are in euthymic states in contrast to the normal controls.

portable_mood_by_alephunky-d5c536zThe research data showed that bipolar disorder patients clustered on the tail end of the distribution indicating a slower alternation rate. The Rivalry Alternation Rates: Bipolar Affective Disorder (n = 18) vs  Non-Clinical Controls (n = 49). Subsequently the euthymic state of the bipolar subjects at the time of testing suggests that slower rivalry rates can be a trait marker for bipolar disorder. Limitations of this study are related to subjects that have unipolar depression who demonstrated slower rivalry rates, although these subjects were to a lesser extent in contrast to bipolar subjects. The model of “bipolar disorder slow switches are ‘sticky’ switches because the intrinsic channel abnormalities that cause the slow oscillation rate also make the switch more likely to be held down in one state by external synaptic inputs”. A neuronal sensitivity with bipolar disorder argues that it would “lead to increased hemispheric output (in response to a stressor) and might therefore increase the likelihood that the switch will be held down (‘stuck’) on the side favouring that hemisphere”.

Pettigrew and Miller propose that the data suggests that bipolar patients have an increased ‘stickiness’ due to reduced intrinsic currents and greater extrinsic synaptic inputs from stressors, resulting in the patients being ‘stuck’ in a depressive or manic episode as a consequence of a stressor. The research proposes that the wide variety of data is indicative of hemispheric asymmetries of mood and mood disorders. Overall the results of the tests in inter-hemispheric switching might also be applicable to understanding the physiological rhythms of mood, cognitive style and other aspects of human brain function. Pettigrew and Miller outline that there have been reports that creativity is enhanced in subjects with mood disorders and also their relatives in contrast to the general population.  The controversial reports of increased creativity raise the potential for an understanding of the consequences associated with slower inter-hemispheric switching and the rhythms of cognitive style that could reveal neural mechanisms of human creativity.

Please note: this is not an academic essay merely a series of different research I found interesting.

Related/interesting sources:

Altshuler, L., Suppes, T., Black, D., Nolen, W., Leverich, G., Keck, P., Frye, M., Kupka, R., McElroy, S., Grunze, H., Kitchen, C. and Post, R. (2006). Lower Switch Rate in Depressed Patients With Bipolar II Than Bipolar I Disorder Treated Adjunctively With Second-Generation Antidepressants. AJP, 163(2), pp.313-315.

Bost-Baxter, E. (2013). ECT in Bipolar Disorder: Incidence of Switch from Depression to Hypomania or Mania. Journal of Depression & Anxiety, 01(05).

Bottlender, R., Sato, T., Kleindienst, N., Strauß, A. and Möller, H. (2004). Mixed depressive features predict maniform switch during treatment of depression in bipolar I disorder. Journal of Affective Disorders, 78(2), pp.149-152.

Buckley, P. (2012). The Neurobiology of the Switch Process in Bipolar Disorder: A Review. Yearbook of Psychiatry and Applied Mental Health, 2012, pp.388-392.

Calabrese, J. (2001). Drug-induced switch rates and their impact in bipolar disorder. European Neuropsychopharmacology, 11, pp.S95-S96.

Goldberg, J. (2010). Substance Abuse and Switch From Depression to Mania in Bipolar Disorder. AJP, 167(7), pp.868-869.

Kauer-Sant’Anna, M. and Yatham, L. (2007). Comment on “antidepressant treatment-emergent switch in bipolar disorder: a prospective case-control study of outcome”. Rev. Bras. Psiquiatr., 29(1), pp.86-87.

Koszewska, I. (1995). P-2-65 Pharmacotherapy in depression during switch from depression to mania in patients with bipolar affective disorder (BD). European Neuropsychopharmacology, 5(3), p.296.

Niitsu, T., Fabbri, C. and Serretti, A. (2014). P.2.d.031 Predictors for manic switch at depressive episodes in bipolar disorder: the Systematic Treatment Enhancement Program for Bipolar Disorder. European Neuropsychopharmacology, 24, pp.S431-S432.

Pettigrew, J. and Miller, S. (1998). A ‘sticky’ interhemispheric switch in bipolar disorder?. Proceedings of the Royal Society B: Biological Sciences, 265(1411), pp.2141-2148.

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10 thoughts on “New Research On The Aetiology Of Bipolar Disorder.”

  1. Reblogged this on James the Greatest and commented:
    “Proposing that bipolar disorder is the product of genetic propensity of slow inter-hemispheric switching mechanisms which can become ‘stuck’ in one particular state. Pettigrew and Miller state that slower switches are more ‘sticky’ in contrast to faster switches, hypothesising that the clinical manifestations of bipolar disorder can possibly be explained by hemispheric activation, which could be caught on the right (depression) or the left (mania).”

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  2. I have to admit that I heard of such a thing as bipolar disorder only after I came over from India, to settle in the west. Maybe my folk back in India are just plain ignorant.

    Maybe sometimes it is better not to know too much about something. Hey, travel to India and you’ll see that folk out there are just happy or sad as you are over here in the west. With nothing.

    Maybe poverty negates bipolarity. Maybe folk who are too poor just don’t have the the wherewithal to be bipolar? No time to feel ill? I don’t know really.

    What did they do, say in 100 BC? Did they have bipolar disorder? What about PTSD ? Did a child or woman in 250 BC Sparta get PTSD from all those invasions? Heck, there was enough provocation, wasn’t there?

    Then, how is it that today, a big deal is made out of stuff that was run-of-the-mill at one time? Are we just making up names for so-called ‘disorders’.

    Take a piece of advice from me. As long as you make your blog, beautiful as it is, a sort of highway marker for a ‘disorder’, you will never ever get over it.

    I still love to read your blog, if only to feel how lucky I am, not to feel sorry for myself all the time. 🙂

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    1. To be honest the lifestyles are completely different between countries and historical periods, who’s to say that countries who are being over stimulated with mass media and the constancy of consumerism are developing changes within the brain (it’s been proven that the brain re-programs overtime to cope with changes). The content that we are constantly consuming is extremely different from ancient civilizations. The above post was not a self-pitying one – I’m happy to have polarities – I also studied psychology for 3 years, this was an investigatory post. I don’t see my blog as a highway for my disorder, I use it to voice opinions I don’t voice offline, I put it on here and put it away in my offline life, my life is simple and mostly happy, please don’t presume that my blog is merely a means to self-pity myself.

      I have noticed in low socio-economic countries that they don’t understand the concept of mental illness, but i partly believe this is due to their constant struggle with daily life which minimises the acknowledgement of mental illness and puts any happiness to the forefront. Whereas in Australia we have the economic freedom to focus on the aspects that are taking away from our potential happiness. It seems that people in poorer countries are happier, but this is mediated through their other struggles. I’ve been overseas, I’ve seen, it doesn’t make mental health non-existent by arguing that it is less prominent in other countries. There is also limited documentation about historical periods and mental health, the works of historians are generally based on secondary sources and bias research data.

      This is an interesting excerpt from a psychology site:
      “But living in poverty for any significant length of time increases all sorts of risk factors for health and mental health problems. You are more stressed, worrying about money constantly, and how you’re going to pay the bills or have enough money to eat. You eat worse because bad, processed food is so often cheaper than nutritional food. If you can still afford to live on your own, you will likely do so in a neighbourhood more prone to violence, exposing you to more trauma and risk for personal violence. It’s a vicious circle where both poverty seems linked to greater rates of mental illness, and in some cases, certain kinds of mental illness seem linked to a greater likelihood of living in poverty.”

      I will admit that too much knowledge can definitely be a bad thing. I will always adamantly defend my reasons for my blog, but this is a mental health blog, I have another blog that is based on ancient history from the research I do in university. They are merely mental outlets for my various interests, from art, history and psychology, all of which I’ve studied. I know this is a long comment, but I always like to over explain myself and my reasoning. Thankyou for your comment, everyone’s opinions are always valid.

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      1. Don’t. You have built up a community, who have grown to love the way you write on this particular challenge. Don’t dilute it.

        Just migrate your other writing into a set of nested pages as I have done on the top of my blog. That way, your main writing (ie: on bipolar disorder) remains front and center while your other pieces form the outer edges.

        Of course if you have already a lot of posts to migrate, it will take a while, since WordPress doesn’t have any means other than copying and pasting the pieces individually, when it comes to posts to pages.

        And thanks for your understanding.

        Like

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