Clinical predictors of post-injury anxiety in adolescent patients following concussion.

The purpose of the current study was to examine predictors (e.g., pre-injury anxiety and sub-types, concussion symptom severity, neurocognitive performance, and vestibular/ocular-motor impairment) of post-injury anxiety scores following concussion among youth aged 10-18 years. This observational cohort study enrolled patients (n = 129) within 30 days of a diagnosed concussion. Patients completed Screening for Child Anxiety Related Disorders-Child Reports (SCARED-C), Generalized Anxiety Disorder-7 (GAD-7), Post-concussion Symptom Scale, neurocognitive testing, and Vestibular-Ocular Motor Screening. Logistic regression analyses were conducted to evaluate the role of risk factors and clinical outcomes as predictors of mild (GAD-7 > 5) and moderate levels (GAD-7 > 10) of post-injury anxiety. Twenty-two percent (n = 28) of patients reported clinical levels of pre-injury anxiety, and 13% (n = 17) reported clinical levels of post-injury anxiety. The logistic regression model predicting mild or greater anxiety was significant (R2 = 31.7%; p < 0.001) and supported pre-injury panic symptoms (OR = 1.38) and total symptom severity (OR = 1.04) as the most robust predictors. The logistic regression model predicting clinical anxiety was significant (R2 = 47.2%; p < 0.001) and supported non-SRC injury type (OR = 9.48), vestibular dysfunction (OR = 1.74) and pre-injury panic symptoms (OR = 1.57) as the most robust predictors. Results suggest that clinicians should employ measures of pre-injury and post-injury emotional functioning when evaluating and treating concussion among adolescents. Moreover, these results highlight the importance of assessing different types of pre-injury and post-injury anxiety in the context of concussion management.

Gender Matters: Nonlinear Relationships Between Heart Rate Variability and Depression and Positive Affect.

Vagally mediated heart rate variability (vmHRV), a measure of the parasympathetic nervous system's control over the heart, is often negatively related to maladaptive emotional outcomes. Recent work suggests that quadratic relationships involving these factors may be present; however, research has not investigated gender differences in these nonlinear functions. To address this gap, the current study tested for quadratic relationships between resting vmHRV and depression and positive affect while investigating gender differences in these relationships. Significant quadratic effects were found between resting vmHRV and reports of both depression symptoms and positive affect in women but not men. Specifically, the lowest levels of depression and the highest levels of positive affect were found at moderate vmHRV in women. These results suggest that examinations of vmHRV's nonlinear associations require the consideration of gender. Our findings are interpreted based on proposed differential neuropsychological mechanisms of vmHRV in men versus women.

Anxiety and Mood Clinical Profile following Sport-related Concussion: From Risk Factors to Treatment.

Conceptual models for assessing and treating sport-related concussion (SRC) have evolved from a homogenous approach to include different clinical profiles that reflect the heterogeneous nature of this injury and its effects. There are six identified clinical profiles, or subtypes from SRC, and one such clinical profile is the anxiety/mood profile. Athletes with this profile experience predominant emotional disturbance and anxiety following SRC. The purpose of this targeted review was to present an overview of the empirical evidence to support factors contributing to the anxiety/mood profile, along with methods of evaluation and treatment of this clinical profile following SRC. We discuss the potential underlying mechanisms and risk factors for this clinical profile, describe comprehensive assessments to evaluate concussed athletes with an anxiety/mood clinical profile, and explore behavioral and other interventions for treating these athletes. Although there is limited, but growing empirical evidence for the anxiety/mood clinical profile following SRC, understanding this clinical profile is germane for clinicians who are treating athletes with emotional sequelae after SRC.

Inducing unconscious stress: Cardiovascular activity in response to subliminal presentation of threatening and neutral words.

Stress-related cognitive processes may occur outside of awareness, here referred to as unconscious stress, and affect one's physiological state. Evidence supporting this idea would provide necessary clarification of the relationship between psychological stress and cardiovascular (CV) health problems. We tested the hypothesis that increases in mean arterial pressure (MAP) and total peripheral resistance (TPR) and decreases in heart rate variability (HRV) would be larger when threatening stimuli are presented outside of awareness, or subliminally, compared with neutral stimuli. Additionally, it was expected that trait worry and resting HRV, as common risk factors for CV disease, would moderate the effect. We presented a subliminal semantic priming paradigm to college students that were randomly assigned to the threat (n = 56) or neutral condition (n = 60) and assessed changes from baseline of MAP, TPR, and HRV. Level of trait worry was assessed with the Penn State Worry Questionnaire. The findings indicate that CV activity changed according to the hypothesized pattern: A higher MAP and TPR and a lower HRV in the threat condition compared with the neutral condition were found with practically meaningful effect sizes. However, these findings were only statistically significant for TPR. Furthermore, changes in CV activity were not moderated by trait worry or resting HRV. This is the first study to explicitly address the role of subliminally presented threat words on health-relevant outcome measures and suggests that unconscious stress can influence peripheral vascular resistance.

Individual differences in resting heart rate variability moderate thought suppression success.

Individual differences in heart rate variability (HRV) at rest are thought to represent an individual's capacity for self-regulation, but it remains unclear whether HRV predicts control over unwanted thoughts. The current study used a thought suppression paradigm in which participants recorded occurrences of a personally relevant intrusive thought over three monitoring periods. Among those instructed to suppress, higher levels of HRV were associated with greater declines in intrusions across the monitoring periods; no such relationship was found among those assigned to a control condition. Resting HRV also interacted with spontaneous thought suppression effort to predict intrusive thought frequency. In both cases, these HRV-related differences in thought suppression success predicted the generalized distress symptoms common to depression and anxiety. These findings enhance understanding of the relationships between HRV and cognitive control and highlight how individual differences in self-regulatory capacity impact thought suppression success and emotion regulation.

Individual differences in resting heart rate variability and cognitive control in posttraumatic stress disorder.

Post-traumatic stress disorder (PTSD) is characterized by deficits in cognitive functioning, particularly cognitive control. Moreover, these deficits are thought to play a critical role in the etiology and maintenance of core PTSD symptoms such as intrusive thoughts and memories. However, the psychophysiological concomitants of cognitive control remain largely unexamined. In this article, we suggest that individual differences in heart rate variability (HRV), a physiological index of self-regulatory capacity, may underlie the association between cognitive control ability and intrusive cognitions in PTSD. We review evidence showing that individual differences in HRV at rest are related to prefrontal cortical activity and performance on a broad range of cognitive control tasks. We highlight the importance of inhibition as a mechanism by which HRV promotes successful cognitive control. In addition, we summarize recent research linking individual differences in HRV to performance on laboratory tasks that assess the ability to control unwanted memories and intrusive thoughts. We conclude by suggesting that future studies should examine the role of low HRV as a risk factor for developing PTSD.

Heart rate variability predicts control over memory retrieval.

Stopping retrieval of unwanted memories has been characterized as a process that requires inhibition. However, little research has examined the relationship between control over memory retrieval and individual differences in inhibitory control. Higher levels of resting heart rate variability (HRV) are associated with greater inhibitory control, as indicated by better performance on a number of cognitive, affective, and motor tasks. Therefore, we tested the hypothesis that higher levels of resting HRV predict enhanced memory inhibition as indexed by performance on the think/no-think task. Efforts to suppress no-think word pairs resulted in impaired recall for those items, as in past studies. Moreover, higher levels of resting HRV were associated with more successful suppression, as indicated by lower recall of the to-be-avoided stimuli relative to baseline stimuli. These findings are among the first to suggest that physiological markers of inhibitory control can be used to index a person's capacity to control unwanted memories.