Startle amplitude during unpleasant pictures is greater in veterans with a history of multiple-suicide attempts and predicts a future suicide attempt

Toward objective characterizations of suicide risk: A narrative review of laboratory-based cognitive and behavioral tasks

Although suicide is a leading cause of preventable death worldwide, current prevention efforts have failed to substantively mitigate suicide risk. Suicide research has traditionally relied on subjective reports that may not accurately differentiate those at high versus minimal risk. This narrative review supports the inclusion of objective task-based measures in suicide research to complement existing subjective batteries. The article: 1) outlines risk factors proposed by contemporary theories of suicide and highlights recent empirical findings supporting these theories; 2) discusses ongoing challenges associated with current risk assessment tools and their ability to accurately evaluate risk factors; and 3) analyzes objective laboratory measures that can be implemented alongside traditional measures to enhance the precision of risk assessment. To illustrate the potential of these methods to improve our understanding of suicide risk, the article reviews how acute stress responses in a laboratory setting can be modeled, given that stress is a major precipitant for suicidal behavior. More precise risk assessment strategies can emerge if objective measures are implemented in conjunction with traditional subjective measures.

Hyperreactivity and Impaired Habituation of Startle Amplitude During Unpleasant Pictures in Borderline but Not Schizotypal Personality Disorder: Quantifying Emotion Dysregulation

BACKGROUND

Borderline personality disorder (BPD) is characterized by greater intensity of reactions to unpleasant emotional cues and a slower-than-normal return of these responses to baseline. Habituation is defined as decreased response to repeated stimulation. Affect-modulated startle (AMS), a translational psychophysiological approach, is mediated by the amygdala and used to study emotion processing in both humans and animals. This is the first study to examine the specificity of habituation anomalies in BPD during passive emotional and neutral picture processing.

METHODS

A total of 90 participants were studied: patients with BPD (n = 35), patients with schizotypal personality disorder (n = 26; included as a psychopathological comparison group), and healthy control subjects (n = 29). Participants received rigorous clinical assessments, and patients were unmedicated. AMS was examined during a series of intermixed unpleasant, neutral, and pleasant pictures.

RESULTS

Compared with the other groups, patients with BPD showed greater overall AMS during unpleasant pictures and prolonged habituation of startle amplitude during unpleasant pictures from early to later trials. The groups did not differ in AMS during neutral or pleasant pictures or self-reported picture valence. Among the patients with BPD, prolonged habituation to unpleasant pictures was associated with greater symptom severity and suicidal/self-harming behavior.

CONCLUSIONS

These findings 1) indicate that abnormal processing of and habituation to unpleasant pictures is observed in BPD but not schizotypal personality disorder, suggesting that these deficits are not simply characteristics of personality disorders in general; 2) are consistent with studies showing deficient amygdala habituation to unpleasant pictures in BPD; and 3) have significant implications for clinical assessment and treatment of BPD, e.g., alternative therapies for BPD such as gradual exposure to unpleasant emotional stimuli or amygdala neurofeedback may aid habituation deficits.

Distinguishing veterans with suicidal ideation from suicide attempt history: The role of emotion reactivity

INTRODUCTION

Growing evidence suggests emotion reactivity-sensitivity and intensity of emotional experience-may represent a diathesis for suicide risk. However, our understanding of its ability to differentiate risk for suicidal ideation (SI) from suicide attempt (SA) is limited.

METHOD

This study compares Veterans with SI (n = 81) to Veterans with SA (n = 177) history on factors relevant to emotion reactivity to determine which variable(s) best differentiate groups. Variables examined are multimodal: (a) self-report: childhood trauma, combat exposure; (b) clinician-assessed: non-suicidal self-injury (NSSI), structured diagnostic interview of psychopathology; and (c) psychophysiological: affect-modulated startle (AMS; proxy for amygdala reactivity and emotion reactivity) to unpleasant pictures was examined in a subset (n = 90).

RESULTS

SA history was independently predicted by NSSI history, MDD, PTSD, and SUD diagnosis. Childhood trauma and combat exposure did not differentiate groups. The composite risk index demonstrated good accuracy (AUC=0.71, sensitivity=0.90, specificity=0.49). Only AMS independently predicted SA history when added to the model and accuracy was improved (AUC=0.82, sensitivity=0.85, specificity=0.56).

CONCLUSION

NSSI history, MDD, PTSD, and SUD diagnosis may be salient risk factors for this population. However, emotion reactivity is a more parsimonious predictor of SA history among Veterans suggesting it is an important treatment target among Veterans with SI.

Is Emotion Dysregulation Associated With Suicidal Ideation in Post 9/11 Veterans?

Emotion dysregulation, a risk factor for suicide ideation and attempts, has not been studied in U.S. veterans of Operations Enduring and Iraqi Freedom and New Dawn (OEF/OIF/OND). Data were collected through standardized telephone interviews and computer-based surveys from 278 OEF/OIF/OND veterans (70.6% male, 29.4% female). Bivariate analyses indicated that emotion dysregulation was associated with suicidal ideation during the past-three-months (r = 0.30, p < 0.05) and lifetime suicide attempts (r = 0.21, p < 0.05). When PTSD and depression symptoms were added to a sequential logistic regression model, emotion dysregulation was no longer significantly associated with ideation or attempt. Emotion dysregulation was associated with suicidal ideation and attempt; however, current distress had greater associations. Dysregulation is one of several factors in veteran suicide risk.

Emotion regulation difficulties are associated with nightmares and suicide attempts in an adult psychiatric inpatient sample

Although many studies have examined potential moderators of the relation between nightmares and suicide, few have examined emotion regulation, particularly utilizing severe populations such as psychiatric inpatients. The present study sought to investigate whether emotion regulation difficulties are associated with nightmares and suicide attempts in an inpatient sample. We included 2,683 psychiatric inpatients ranging from 18 to 81 years (M = 34.35, SD = 14.70). Nightmare frequency, emotion regulation difficulties, and their interaction predicted previous suicide attempts. Limitations include the homogeneity and cross-sectional nature of the sample. Suggestions for future study are discussed.

Affective startle modulation and psychopathology: Implications for appetitive and defensive brain systems

Startle reflex potentiation versus startle attenuation to unpleasant versus pleasant stimuli likely reflect priming of the defensive versus appetitive motivational systems, respectively. This review summarizes and systemizes the literature on affective startle modulation related to psychopathologies with the aim to reveal underlying mechanisms across psychopathologies. We found evidence for psychopathologies characterized by increased startle potentiation to unpleasant stimuli (anxiety disorders), decreased startle potentiation to unpleasant stimuli (psychopathy), decreased startle attenuation to pleasant stimuli (ADHD), as well as a general hyporeactivity to affective stimuli (depression). Increased versus decreased startle responses to disorder-specific stimuli characterize specific phobia and drug dependence. No psychopathology is characterized by increased startle attenuation to standard pleasant stimuli or a general hyperreactivity to affective stimuli. This review indicates that the defensive and the appetitive systems operate independently mostly in accordance with the motivational priming hypothesis and that affective startle modulation is a highly valuable paradigm to unraveling dysfunctions of the defensive and appetitive systems in psychopathologies as requested by the Research Domain Criteria initiative.

Posttraumatic stress disorder clusters and suicidal ideation

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with suicidal ideation and behavior. However, less is known about how the PTSD symptom clusters, namely alterations in arousal and reactivity (AAR), negative alterations in cognitions and mood (NACM), avoidance, and intrusion, uniquely relate to suicidal ideation. This study aimed to characterize the associations among suicidal ideation and these symptom clusters.

METHODS

Study 1 (n = 346) and Study 2 (n = 194) included community members and treatment-seeking adults at an anxiety specialty clinic, respectively. Participants completed measures of trauma exposure, PTSD symptoms, and suicidal ideation.

RESULTS

In both studies, suicidal ideation significantly and positively correlated with all PTSD factors. In Study 1, Wald tests of parameter constraints indicated that NACM and AAR had the strongest associations with suicidal ideation, followed by intrusion and avoidance. Results were replicated when restricting the sample to individuals with probable PTSD. In Study 2, suicidal ideation significantly and positively correlated with all PTSD factors; there were no differences in the strength of the suicidal ideation-PTSD factors relations.

LIMITATIONS

The studies were cross-sectional and relied on a single-item measure of suicidal ideation.

DISCUSSION

All PTSD factors significantly and positively correlated with suicidal ideation, and the NACM and AAR PTSD clusters were most strongly associated with suicidal ideation in Study 1. Therefore, clinicians should be cautious to thoroughly screen patients with elevations on these PTSD cluster scores for suicide risk.

Psychoneurometric assessment of dispositional liabilities for suicidal behavior: phenotypic and etiological associations

BACKGROUND

Can core genetic liabilities for suicidal behavior be indexed using psychological and neural indicators combined? The current work addressed this question by examining phenotypic and genetic associations of two biobehavioral traits, threat sensitivity (THT) and disinhibition (DIS) - operationalized as psychoneurometric variables (i.e., composites of psychological-scale and neurophysiological measures) - with suicidal behaviors in a sample of adult twins.

METHODS

Participants were 444 identical and fraternal twins recruited from an urban community. THT was assessed using a psychological-scale measure of fear/fearlessness combined with physiological indicators of reactivity to aversive pictures, and DIS was assessed using scale measures of disinhibitory tendencies combined with indicators of brain response from lab performance tasks. Suicidality was assessed using items from structured interview and questionnaire protocols.

RESULTS

THT and DIS each contributed uniquely to prediction of suicidality when assessed psychoneurometrically (i.e., as composites of scale and neurophysiological indicators). In addition, these traits predicted suicidality interactively, with participants high on both reporting the greatest degree of suicidal behaviors. Biometric (twin-modeling) analyses revealed that a high percentage of the predictive association for each psychoneurometric trait (83% for THT, 68% for DIS) was attributable to genetic variance in common with suicidality.

CONCLUSIONS

Findings indicate that psychoneurometric assessments of biobehavioral traits index genetic liability for suicidal behavior, and as such, can serve as innovative targets for research on core biological processes contributing to severe psychopathology, including suicidal proclivities and actions.

From ideation to action: recent advances in understanding suicide capability

Suicide capability is one of few risk factors associated with suicide attempts among ideators. In the decade since the Interpersonal Psychological Theory of Suicide introduced the concept of acquired capability (i.e. the ability to face the fear and pain associated with death), understanding of the capability to attempt suicide has grown. Acquired (e.g. NSSI), dispositional (e.g. genetic), and practical contributors (e.g. access to firearms) appear to influence suicide capability via mechanisms such as the fear of death, persistence through pain, and familiarity with suicide methods. Self-report methods have shown mixed results, highlighting the importance of developing behavioral measures of suicide capability.