Do you have Trichotillomania? Me too. This book provides reliable information on hair pulling, self-help resources to get you started on your healing journey, and includes my own personal story of hair pulling. I hope this helps generate compassiona...
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1) Genetics Research indicates some people may have an inherited predisposition for hair pulling. Several studies have shown a higher number of Body Focused Repetitive Behaviours (BFRBs) in immediate family members of persons with hair pulling disorders than would be expected in the general population. In addition, a recent study examined hair pulling in both identical and fraternal twins and produced results consistent with a significant inherited component in hair pulling disorder. So we can safely say BFRBs are more than likely inherited, at least to some degree.
2) Temperament, Age of onset, and Environmental Stress Factors Even if a predisposition toward BFRBs is inherited, there are other factors involved as well, including temperament, age of onset, and environmental stress factors. It's possible a person can have a predisposition to pick, and the right stressor doesn't happen at the right time, so the behavior never manifests. Conversely, when a person starts experiencing hair pulling, it's not helpful to blame any one aspect of that person's life that is happening at that time, but one might assume that the behavior most likely would have come to light at some point in the person's life.
3) Structural and functional brain abnormalities (within brain areas implicated in habit formation) One study found subcortical brain abnormalities in trichotillomania, including: - Significant volume reductions of the leftputamen and rightamygdala. - Subtle localized abnormalities in the curvature of the putamen, caudate, nucleus accumbens, and amygdala. Thus, abnormalities of neural nodes mediating affect regulation, reward-processing, and habit generation, all appear to be involved in the pathophysiology of trichotillomania. - Increased grey matter densities in the left striatum, left amygdalo-hippocampal formation, and multiple (including cingulate, supplementary motor, and frontal) cortical regions bilaterally. - Excess cortical thickness in a cluster maximal at right inferior frontal gyrus. Morphometric changes in the right inferior frontal gyrus appear to play a central role in the pathophysiology of trichotillomania.
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Putamen's Role: - Key component in motor control. Is involved in lower-level stimulus-response habit learning and response suppression across species. Amygdala's Role: - Traditionally held to be important in fear-processing. Caudate's Role: - Plays a role in directed-learning (such as during complex planning or high-level flexible learning tasks). Nucleus Accumben's Role: - Plays a role in impulsivity, including in temporal reward discounting, and premature responding. In a previous functional neuroimaging study, individuals with trichotillomania showed decreased activation of nucleus accumbens during reward anticipation. Stratium's Role - Critical component of the motor and reward systems.
More than likely BFRBs are caused by a variety of factors that interact with each other, resulting in the behavior.
Animal Studies One interesting point is that other species engage in similar behaviors. Primates such as the great apes or certain types of monkeys will pull hair, over-groom, and pick at nits and insects on their own fur and the fur of others. Birds will pull out their feathers; mice will pull fur or "barber" themselves and their cage mates; dogs and cats may lick their skin or bite at an area, removing fur until there are bald spots. Researchers interested in animal models of BFRBs are trying to understand these behaviors in animals in order to shed some light on the complex neurobiology that underlies the human experience of BFRBs. What these animal studies tell us is that BFRBs are likely, in part, hard-wired behaviors that are not solely the result of environmental factors.
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References [1] https://www.bfrb.org/faqs/what-causes-bfrbs [2] Isobe M, Redden SA, Keuthen NJ, Stein DJ, Lochner C, Grant JE, Chamberlain SR. Striatal abnormalities in trichotillomania: a multi-site MRI analysis. Neuroimage Clin. 2018;17:893-898. doi: 10.1016/j.nicl.2017.12.031. Epub 2017 Dec 22. PMID: 29515968; PMCID: PMC5836997. [3] Chamberlain SR, Menzies LA, Fineberg NA, Del Campo N, Suckling J, Craig K, Müller U, Robbins TW, Bullmore ET, Sahakian BJ. Grey matter abnormalities in trichotillomania: morphometric magnetic resonance imaging study. Br J Psychiatry. 2008 Sep;193(3):216-21. doi: 10.1192/bjp.bp.107.048314. PMID: 18757980; PMCID: PMC2806575. [4] Chamberlain SR, Harries M, Redden SA, Keuthen NJ, Stein DJ, Lochner C, Grant JE. Cortical thickness abnormalities in trichotillomania: international multi-site analysis. Brain Imaging Behav. 2018 Jun;12(3):823-828. doi: 10.1007/s11682-017-9746-3. PMID: 28664230; PMCID: PMC5640149.
