Despite nonoverlapping diagnostic criteria, internalizing and externalizing disorders show substantial comorbidity. This comorbidity is attributable, at least in part, to transdiagnostic neuroaffective mechanisms. Both unipolar depression and externalizing disorders are characterized by structural and functional compromises in the striatum and its projections to the anterior cingulate cortex (ACC) and other frontal regions. Smaller volumes and dampened reward responding in these regions are associated with anhedonia and irritability – mood states that cut across the internalizing and externalizing spectra. In contrast, smaller amygdala volumes and dampened amygdala function differentiate externalizing disorders from internalizing disorders. Little is known, however, about associations between internalizing–externalizing comorbidity and brain volumes in these regions, or whether such patterns differ by sex. Using a transdiagnostic, research domain criteria (RDoC)-informed approach, we evaluate associations between heterotypic (Internalizing × Externalizing) symptom interactions and striatal, amygdalar, and ACC volumes among participants in the Adolescent Brain Cognitive Development study (N = 6,971, mean age 9.9 years, 51.6% female). Heterotypic symptoms were associated with ACC volumes for both sexes, over and above the main effects of internalizing and externalizing alone. However, heterotypic comorbidity was associated with larger ACC volumes for girls, but with smaller ACC volumes for boys. These findings suggest a need for further studies and transdiagnostic assessment by sex.

This article focuses on one potential motivation for a state's behaviour in international affairs, namely status-seeking, in order to shed light on Norway's Arctic politics and to discuss the role of hierarchies in Arctic politics more generally. The idea that a state's political elite seek national security and economic gain is well established in international relations (IR) literature. However, another key motivation of human behaviour – seeking status and respect – is frequently overlooked as a potential factor shaping states’ behaviour. The argument begins with a brief review of post-cold war Arctic politics followed by a discussion of the status-related literature in IR. Norway's position in the Arctic Council (AC) and in bilateral relations with Russia is then examined, with particular attention paid to the extent to which other Arctic states acknowledge and confirm Norway's status claims. Norway's status as an information provider, a convener and a bridge to Russia gives the country a degree of influence in Arctic multilateral settings. Given the Arctic region's relatively peaceful nature and the emphasis on circumpolar cooperation, space has been made for creative approaches to status. Size and military or economic greatness are not always decisive factors for taking a lead in today's Arctic politics.

Since the end of the Cold War, cooperative and region-building endeavours involving Arctic governments and peoples have flourished. These efforts have been rooted in a desire to pursue northern sustainable development and in assertions about the shared experiences and values of Arctic states and peoples. In this paper, a case study is presented concerning a Canadian development project designed to promote Canadian sustainable economic development models to indigenous and non-indigenous leaders and bureaucrats in the Russian north. In their efforts to move knowledge across northern borders, the Canadian project team relied clearly upon two central discourses of the Arctic region-building process: a common Arctic space and the shared pursuit of sustainable development. Drawing upon over thirty qualitative interviews and a year of participant observation at project events, the aim of this article is to map the currency and reach of these Arctic regional discourses at a more ‘local’ level amongst the Russian and Canadian Arctic residents involved in the project. The continuing debate during this development project over what Arctic regionalism and sustainable development mean in practice calls into question a key assertion of contemporary region-building rhetoric, the assumption or hopeful injunction that not only is a regional landscape or environment shared but that values and experiences are, or will come to be, shared as well.