ABSTRACT
This study examined the temporal relation between self-competence (academic, social, athletic, physical appearance, and close friend) and depressive symptoms in a large, diverse community sample of 636 adolescents. Surveys were administered to all 10th- and 11th-grade students at participating high schools at baseline (mean age = 16.10, SD = .71) and 1 year later. Girls reported higher levels of self-competence in close friendships and more depressive symptoms, whereas boys reported higher levels of self-competence in athletics and physical appearance. However, there were no gender differences in the associations between self-competence and depressive symptoms. Results from autoregressive, cross-lagged path analyses indicated that depressive symptoms predicted self-competence more consistently than self-competence predicted depressive symptoms during middle-late adolescence. Implications for prevention are discussed.
Subject(s)
Depression/psychology , Friends/psychology , Physical Appearance, Body/physiology , Sports/psychology , Academic Success , Adolescent , Case-Control Studies , Depression/epidemiology , Depression/ethnology , Depression/prevention & control , Female , Humans , Male , Predictive Value of Tests , Schools/statistics & numerical data , Self Concept , Surveys and Questionnaires , Time Factors , United States/epidemiologyABSTRACT
Cerebral blood flow is highly sensitive to changes in CO2/H+ where an increase in CO2/H+ causes vasodilation and increased blood flow. Tissue CO2/H+ also functions as the main stimulus for breathing by activating chemosensitive neurons that control respiratory output. Considering that CO2/H+-induced vasodilation would accelerate removal of CO2/H+ and potentially counteract the drive to breathe, we hypothesize that chemosensitive brain regions have adapted a means of preventing vascular CO2/H+-reactivity. Here, we show in rat that purinergic signaling, possibly through P2Y2/4 receptors, in the retrotrapezoid nucleus (RTN) maintains arteriole tone during high CO2/H+ and disruption of this mechanism decreases the CO2ventilatory response. Our discovery that CO2/H+-dependent regulation of vascular tone in the RTN is the opposite to the rest of the cerebral vascular tree is novel and fundamentally important for understanding how regulation of vascular tone is tailored to support neural function and behavior, in this case the drive to breathe.
