مقاله انگلیسی رایگان در مورد نظریه سیستم دوگانه اختلالات طیف دو قطبی: فراتحلیل – الزویر 2021

t Bipolar spectrum disorders are characterized by alternating intervals of extreme positive and negative affect. We performed a meta-analysis to test the hypothesis that such disorders would be related to dysregulated reinforcement sensitivity. First, we reviewed 23 studies that reported the correlation between self-report measures of (hypo)manic personality and measures of reinforcement sensitivity. A large relationship was found between (hypo)manic personality and BAS sensitivity (g = .74), but not with BIS sensitivity (g = -.08). This stands in contrast to self-reported depression which has a small, negative relationship with BAS sensitivity and a large positive one with BIS sensitivity (Katz et al., 2020). Next, we reviewed 33 studies that compared reinforcement sensitivity between euthymic, bipolar participants and healthy controls. There, bipolar disorder had a small, positive relationship with BAS sensitivity (g = .20) and a medium, positive relationship with BIS sensitivity (g = .64). These findings support a dualsystem theory of bipolar disorders, wherein BAS sensitivity is more closely related to mania and BIS sensitivity more closely to bipolar depression. Bipolar disorders show diatheses for both states with euthymic participants being BAS- and BIS- hypersensitive. Implications for further theory and research practice are expounded upon in the discussion.

The bipolar spectrum contains a set of related disorders characterized by the periodic experiencing of emotional extremes (American Psychiatric Association, 2013). Those who suffer from a bipolar spectrum disorder have typically experienced periods of abnormally elevated, energetic or irritable moods as well as periods of lethargy and anhedonia – sometimes rapidly cycling between both, and sometimes experiencing both simultaneously. Although a diagnosis of Bipolar I disorder (BP-I) requires only a manic episode (American Psychiatric Association, 2013), a recent, large-scale survey of those diagnosed with BP-I found that the vast majority have experienced at least one depressive episode as well (e.g., 94.2%; Karanti et al., 2020). A diagnosis of Bipolar II (BP-II), on the other hand, entails the history of a less severe manic episode along with a depressive episode (American Psychiatric Association, 2013). Cyclothymic disorder involves numerous cycles of subthreshold manic and depressive episodes. Final diagnosis often reflects the relative severity of each bipolar episode. Severe impairment due to mania/hypomania is somewhat more common among those with BP-I than with BP-II (e.g., 73.1% vs 64.6%), while severe impairment due to a depressive episode is slightly more likely among those with BP-II than in BP-I (e.g., 91.4% vs 89.3%; Merikangas et al., 2007). While the relative severities of each bipolar episode may shift based on disorder, bipolar spectrum disorders typically share the primary experience of alternating between extremes.