Matthew K Nock

Harvard University | Harvard · Department of Psychology

Childhood adversity (CA) is associated with increased risk of negative health outcomes. Research implicates brain structure following CA as a key mechanism of this risk, and recent models suggest different forms of adversity differentially impact neural structure as a function of development (accelerated or attenuated development). Employing the Di...

The goal of this research was to expand theoretical models of adolescent suicide by exploring whether individual differences in adolescent girls’ need for approval (NFAavoid and NFAapproach) contribute to risk for, or protection against, self-injurious thoughts and behaviors (SITBs). We examined these novel hypotheses in a series of concurrent and...

Most theories of suicide suggest that it occurs as a result of negative affect, but surprisingly few studies test nuanced associations between negative affect and suicidal thoughts. We hypothesized that negative affect would be especially likely to predict suicidal thoughts among those with strong emotion reactivity: that is, those with greater sen...

Background Real-time monitoring captures information about suicidal thoughts and behaviors (STBs) as they occur and offers great promise to learn about STBs. However, this approach also introduces questions about how to monitor and respond to real-time information about STBs. Given the increasing use of real-time monitoring, there is a need for nov...

Objectives To develop a composite score for differential resilience to effects of combat‐related stressors (CRS) on persistent DSM‐IV post‐traumatic stress disorder (PTSD) among US Army combat arms soldiers using survey data collected before deployment. Methods A sample of n = 2542 US Army combat arms soldiers completed a survey shortly before dep...

Suicide risk is highest immediately after psychiatric hospitalization, but the field lacks methods for identifying which patients are at greatest risk, and when. We built personalized models predicting suicidal thoughts after psychiatric hospital visits (N = 89 patients), using ecological momentary assessment (EMA; average EMA responses per partici...

Researchers often want to measure a broad variety of constructs such as anxiety, discrimination, or loneliness in text data from surveys, academic articles, interviews, social media, and electronic health records. In practice, using large language models (LLMs) remain infeasible for many researchers due to concerns around privacy, cost, compute req...

Self-harm is when someone hurts themselves on purpose, regardless of the reasons for doing this. Often, shame and stigma stop people from seeking help. Self-harming behaviour increases the risk of death by suicide, and it is a common cause of disability in young people. Currently, people attending health services only represent the tip of the icebe...

Self-harm is when someone hurts themselves on purpose, regardless of the reasons for doing this. Often, shame and stigma stop people from seeking help. Self-harming behaviour increases the risk of death by suicide, and it is a common cause of disability in young people. Currently, people attending health services only represent the tip of the icebe...

Background Smartphone-based monitoring in natural settings provides opportunities to monitor mental health behaviors, including suicidal thoughts and behaviors. To date, most suicidal thoughts and behaviors research using smartphones has primarily relied on collecting so-called “active” data, requiring participants to engage by completing surveys....

Approximately 9% of people think about suicide during their lifetime. Suicidal thoughts are consistently associated with perceived failures in emotion regulation. However, factors contributing to these perceptions remain insufficiently clear. New evidence suggests that when people know little about the cause of their emotions (i.e., low source attr...

Background The period after psychiatric hospital discharge is one of elevated risk for suicide‐related behaviors (SRBs). Post‐discharge clinical outreach, although potentially effective in preventing SRBs, would be more cost‐effective if targeted at high‐risk patients. To this end, a machine learning model was developed to predict post‐discharge su...

Importance A major portion of adolescents and adults seeking psychiatric treatment report nonsuicidal self-injury (NSSI) within the past month, yet the short-term course of NSSI among these patients remains poorly understood. Objective To advance the understanding of the short-term course of NSSI cognitions (ie, thoughts, urges, and self-efficacy...

Background While previous studies have reported high rates of documented suicide attempts (SAs) in the U.S. Army, the extent to which soldiers make SAs that are not identified in the healthcare system is unknown. Understanding undetected suicidal behavior is important in broadening prevention and intervention efforts. Methods Representative survey...

Most studies aimed at understanding suicidal behavior have focused on quantifying the associations between putative risk factors and suicidal behavior in comparative studies of cases and controls. The current study, in comparison, exclusively focused on cases—89 Army soldiers presenting for hospital care following a suicide attempt—and attempted to...

Background Military Servicemembers and Veterans are at elevated risk for suicide, but rarely self-identify to their leaders or clinicians regarding their experience of suicidal thoughts. We developed an algorithm to identify posts containing suicide-related content on a military-specific social media platform. Methods Publicly-shared social media p...

Introduction The transition from suicidal thoughts to behaviors often involves considering the consequences of suicide as part of the decision‐making process. This study explored the relationship between this consideration process and the decision to either abort or carry out a suicide attempt. Methods Among inpatients with a suicide‐related event...

The weeks following an inpatient psychiatric hospitalization are known to be the highest-risk time for suicide. Interventions are needed that are well-matched to the dynamic nature of suicidal thoughts and easily implementable during this high-risk time. We sought to determine the feasibility and acceptability of a novel registered clinical trial t...

Introduction Little research has been done on how people mentally simulate future suicidal thoughts and urges, a process we term suicidal prospection . Methods Participants were 94 adults with recent suicidal thoughts. Participants completed a 42‐day real‐time monitoring study and then a follow‐up survey 28 days later. Each night, participants pro...

BACKGROUND Despite growing interest in the clinical translation of polygenic risk scores (PRS), it remains uncertain to what extent genomic information can enhance the prediction of psychiatric outcomes beyond the data collected during clinical visits alone. OBJECTIVE To assess the clinical utility of incorporating PRS into a suicide risk predicti...

Background Despite growing interest in the clinical translation of polygenic risk scores (PRSs), it remains uncertain to what extent genomic information can enhance the prediction of psychiatric outcomes beyond the data collected during clinical visits alone. Objective This study aimed to assess the clinical utility of incorporating PRSs into a su...

BACKGROUND Real-time monitoring captures information about suicidal thoughts and behaviors (STBs) as they occur and offers great promise to learn about STBs. However, this approach also introduces questions about how to monitor and respond to real-time information about STBs. Given the increasing use of real-time monitoring, there is a need for nov...

Introduction: Suicide loss survivors can provide information not otherwise available about the circumstances preceding a suicide. In this study, we analyzed interview data from suicide loss survivors collected as part of a psychological autopsy study of U.S. Army soldiers. Methods: Next-of-kin (NOK) (n = 61) and Army supervisors (SUP) (n = 107) of...

Despite copious data linking brain function with changes to social behavior and mental health, little is known about how puberty relates to brain functioning. We investigated the specificity of brain network connectivity associations with pubertal indices and age to inform neurodevelopmental models of adolescence. We examined how brain network conn...

Patients experiencing mental health crises often seek help through messaging-based platforms, but may face long wait times due to limited message triage capacity. Here we build and deploy a machine-learning-enabled system to improve response times to crisis messages in a large, national telehealth provider network. We train a two-stage natural lang...

Ecological momentary assessment (EMA) is increasingly used to study suicidal thoughts and behaviors (STBs). There is a potential ethical obligation for researchers to intervene when receiving information about suicidal thoughts in real time. A possible concern, however, is that intervening when receiving responses that indicate high risk for suicid...

This handbook is currently in development, with individual articles publishing online in advance of print publication. At this time, we cannot add information about unpublished articles in this handbook; however, the table of contents will continue to grow as additional articles pass through the review process and are added to the site. Please note...

Importance Psychiatric hospitalization is the standard of care for patients presenting to an emergency department (ED) or urgent care (UC) with high suicide risk. However, the effect of hospitalization in reducing subsequent suicidal behaviors is poorly understood and likely heterogeneous. Objectives To estimate the association of psychiatric hosp...

People’s ability to regulate emotions is crucial to healthy emotional functioning. One overlooked aspect in emotion-regulation research is that knowledge about the source of emotions can vary across situations and individuals, which could impact people’s ability to regulate emotion. Using ecological momentary assessments ( N = 396; 7 days; 5,466 ob...

Background Suicidal behaviors are prevalent among college students; however, students remain reluctant to seek support. We developed a predictive algorithm to identify students at risk of suicidal behavior and used telehealth to reduce subsequent risk. Methods Data come from s everal waves of a prospective cohort study (2016–2022) of college stude...

Although the literature suggests trait-like differences in affective and cognitive vulnerabilities between individuals with and without a history of non-suicidal self-injury (NSSI), little is known about how these dispositional differences are experienced in the natural environment. The present study compares the intensity, inertia, interaction, an...

Introduction Psilocybin use has been linked to lowered odds of crime-related outcomes across a host of observational studies. No studies have investigated how these associations may differ among those of different races and ethnicities. Methods Using a nationally-representative sample of 734,061 adults from the National Survey on Drug Use and Heal...

Background: Nonsuicidal self-injury (NSSI) is a major mental health concern. Despite increased research efforts on establishing the prevalence and correlates of the presence and severity of NSSI, we still lack basic knowledge of the course, predictors, and relationship of NSSI with other self-damaging behaviors in daily life. Such information will...

Objective: Little is known about how female adolescent ballet dancers-a group at high-risk for the development of body dissatisfaction and eating disorders-construct body ideals, and how their social identities interact with body ideals to confer risk for disordered eating. Using a novel body figure behavioral task, this study investigated (1) whe...

Adverse social experiences are often linked to suicidal behavior in adolescence, perhaps particularly for girls. Social problem-solving abilities may indicate more or less adaptive responses to adverse social experiences that contribute to adolescent girls' risk for suicidal behavior. While social problem-solving is implicated in cognitive and beha...

This study examined descriptions of suicidal thoughts and behavior (STB) to identify risk and protective factors that may present in clinical settings among university students from Latin America. Our focus was on answering the following key questions: How are suicidal thoughts and behavior described? What are reasons for wanting to die and for liv...

This study aims to identify the timescale of suicidal thinking, leveraging real-time monitoring data and a number of different analytic approaches. Participants were 105 adults with past week suicidal thoughts who completed a 42-d real-time monitoring study (total number of observations = 20,255). Participants completed two forms of real-time asses...

Nine percent of people worldwide report thinking about suicide at some point during their lives. A fundamental question we currently lack a clear answer to is: why do suicidal thoughts persist over time? One possibility is that suicidal thoughts serve adaptive functions for people who experience them. We tested whether suicidal thinking may serve a...

Adolescents' suicidal behavior frequently is preceded by interpersonal stress, but not all who experience distress attempt to end their lives. Recent theories have posited individual differences in stress-related inflammatory reactivity may be associated with psychopathology risk; this study examined inflammatory reactivity as a moderator of the pr...

Several recent studies have applied machine learning techniques to develop risk algorithms that predict subsequent suicidal behavior based on electronic health record data. In this study we used a retrospective cohort study design to test whether developing more tailored predictive models—within specific subpopulations of patients—would improve pre...

Importance The months after psychiatric hospital discharge are a time of high risk for suicide. Intensive postdischarge case management, although potentially effective in suicide prevention, is likely to be cost-effective only if targeted at high-risk patients. A previously developed machine learning (ML) model showed that postdischarge suicides ca...

Objectives: To identify the extent to which the presence of recent stressful events are risk factors for suicide among active-duty soldiers as reported by informants. Methods: Next-of-kin (NOK) and supervisors (SUP) of active duty soldiers (n = 135) who died by suicide and two groups of living controls: propensity-matched (n = 128) and soldiers...

Clinical risk prediction models powered by electronic health records (EHRs) are becoming increasingly widespread in clinical practice. With suicide-related mortality rates rising in recent years, it is becoming increasingly urgent to understand, predict, and prevent suicidal behavior. Here, we compare the predictive value of structured and unstruct...

Suicide is among the most devastating problems facing clinicians, who currently have limited tools to predict and prevent suicidal behavior. Here we report on real-time, continuous smartphone and sensor data collected before, during, and after a suicide attempt made by a patient during a psychiatric inpatient hospitalization. We observed elevated a...

Introduction: The inclusion of suicide gestures in modern nomenclatures for self-injurious thoughts and behaviors (SITB) is contentious due to their history of pejorative connotations and inconsistent operationalization and measurement. Here we sought to investigate the extent to which participants who endorse this behavior on a standardized SITB...

The ILHBN is funded by the National Institutes of Health to collaboratively study the interactive dynamics of behavior, health, and the environment using Intensive Longitudinal Data (ILD) to (a) understand and intervene on behavior and health and (b) develop new analytic methods to innovate behavioral theories and interventions. The heterogenous st...

Although the literature suggests trait-like differences in affective and cognitive vulnerabilities between individuals with and without a history of non-suicidal self-injury (NSSI), little is known about how these dispositional differences are experienced in the natural environment. In the present study, we compare the intensity, stability, interac...

Background Although non-suicidal self-injury (NSSI) is known typically to begin in adolescence, longitudinal information is lacking about patterns, predictors, and clinical outcomes of NSSI persistence among emerging adults. The present study was designed to (1) estimate NSSI persistence during the college period, (2) identify risk factors and high...

The motivation to socially connect with peers increases during adolescence in parallel with changes in neurodevelopment. These changes in social motivation create opportunities for experiences that can impact risk for psychopathology, but the specific motivational presentations that confer greater psychopathology risk are not fully understood. To a...

Background People engage in nonsuicidal self-injury (NSSI) to reduce negative affect, but it is not clear why they engage in this harmful type of behavior instead of using healthier strategies. The primary goal of this study was to evaluate whether people choose NSSI to reduce negative affect because they perceive it to be less cognitively costly t...

Little is known about how female adolescent ballet dancers—a group at high-risk for the development of body dissatisfaction and eating disorders—construct body ideals, and how their social identities interact with body ideals to confer risk for disordered eating. Using a novel body figure behavioral task, this study investigated (1) whether degree...

Objective: Suicide is a major public health concern in the United States, but few effective and scalable interventions exist to help those with suicidal thoughts. We hypothesized that reading first-person narratives about working through suicidal thoughts would reduce the desire to die among adults and that this effect would be mediated by increas...

Psychology is a popular subject to study, with thousands entering graduate school each year, but unlike med or pre-law, there is limited information available to help students learn about the field, how to successfully apply, and how to thrive while completing doctoral work. The Portable Mentor is a useful, must-have resource for all students inter...

The suicide rate (currently 14 per 100,000) has barely changed in the United States over the past 100 years. There is a need for new ways of preventing suicide. Further, research has revealed that suicidal thoughts and behaviors and the factors that drive them are dynamic, heterogeneous, and interactive. Most existing interventions for suicidal tho...

The first year of college may carry especially high risk for onset of alcohol use disorders. We assessed the one-year incidence of alcohol use disorders (AUD) among incoming first-year students, predictors of AUD-incidence, prediction accuracy and population impact. A prospective cohort study of first-year college students (baseline: N = 5843; resp...

Cross-sectional studies and prospective studies with long follow-up periods (e.g., years) have shown that lower levels of social support are associated with nonsuicidal self-injury (NSSI) among adolescents. This study examined how short-term changes in social support may contribute to NSSI behavior and whether different sources of support (e.g., fr...

Despite significant advances in early-intervention services for psychosis, delays in identifying patients continue to impede the delivery of prompt and effective treatments. We sought to develop and preliminarily validate a self-administered psychosis implicit association task (P-IAT) as a screening and diagnostic support tool for identifying indiv...

Background Depression and anxiety are both prevalent among university students. They frequently co-occur and share risk factors. Yet few studies have focused on identifying students at highest risk of first-onset and persistence of either of these conditions. Methods Multicenter cohort study among Spanish first-year university students. At baselin...

Significance Using language to “distance” ourselves from distressing situations (i.e., by talking less about ourselves and the present moment) can help us manage emotions. Here, we translate this basic research to discover that such “linguistic distancing” is a replicable measure of mental health in a large set of therapy transcripts ( N = 6,229)....

Background Interest in developing machine learning models that use electronic health record data to predict patients’ risk of suicidal behavior has recently proliferated. However, whether and how such models might be implemented and useful in clinical practice remain unknown. To ultimately make automated suicide risk–prediction models useful in pra...

Prior research has struggled to differentiate cortisol stress response patterns reflective of well-regulated versus dysregulated hypothalamic–pituitary–adrenal (HPA) axis function among adolescents. Here, we show how exploring profiles of joint HPA– inflammatory stress responsivity, and linking those profiles to pubertal development and peer stress...

Background: Medically ill youth are at increased suicide risk, necessitating early detection. This study aimed to assess the feasibility of administering the Death Implicit Association Test (Death IAT) to pediatric medical inpatients. Methods: Participants completed measures including the Ask Suicide-Screening Questions (ASQ) and the Death IAT. Res...

Objective: The purpose of this study was to examine implicit affect toward suicide (i.e., how good/bad suicide is perceived). Some people might be more likely to think about/choose suicide because they perceive it as a good option (to gain relief) relative to available alternatives. Method: Implicit affect toward suicide among adults (N = 72) an...

Importance: Half of the people who die by suicide make a health care visit within 1 month of their death. However, clinicians lack the tools to identify these patients. Objective: To predict suicide attempts within 1 and 6 months of presentation at an emergency department (ED) for psychiatric problems. Design, setting, and participants: This p...

Inleiding: Er is weinig bekend over epidemiologische aspecten (prevalentie, comorbiditeit, impact en zorggebruik) van de depressieve stoornis bij universiteitsstudenten. In een descriptief-epidemiologisch onderzoek naar de depressieve stoornis (volgens DSM-IV) bij eerstejaarsstudenten aan de KU Leuven, België, werden de 12-maanden prevalentie, de p...

Bckground Theories of suicide suggest that suicidal ideation (SI) results in part from difficulty imagining the future, which itself relies on the ability to remember the past. The present study examines multiple components of episodic future thinking and memory including event richness, which is commonly measured within the cognitive literature bu...

This chapter describes the role of machine learning in youth suicide prevention. Following a brief history of suicide prediction, research is reviewed demonstrating that machine learning can enhance suicide prediction beyond traditional clinical and statistical approaches. Strategies for internal and external model evaluation, methods for integrati...

There has been growing interest in using wearable physiological monitors to passively detect the signals of distress (i.e., increases in autonomic arousal measured through increased electrodermal activity [EDA]) that may be imminently associated with suicidal thoughts. Before using these monitors in advanced applications such as creating suicide ri...

Background Stressful life events are a common antecedent of suicidal thoughts. However, not all stressful events lead to increased suicidal thinking, even among those who frequently have suicidal thoughts. In this study, we examined whether the ways that individuals regulate their emotions moderates the association between stressful events and suic...

Background and objectives Individuals with disordered eating display heightened attentional biases towards food- and body-related stimuli. However, it is unknown whether these attentional biases reflect maladaptive thinking/eating pathology. We investigated the differences between maladaptive and adaptive ways of thinking about food by assessing fo...

Introduction Emotion reactivity (ER) and distress intolerance (DI) may be associated with increased suicide attempt (SA) risk among U.S. Army soldiers. Method In this case–control study, 74 soldiers recently hospitalized for SA (cases) were compared with 133 control soldiers from the same Army installations selected based on either propensity scor...

Every day, individuals post suicide notes on social media asking for support, resources, and reasons to live. Some posts receive few comments while others receive many. While prior studies have analyzed whether specific responses are more or less helpful, it is not clear if the quantity of comments received is beneficial in reducing symptoms or in...

Objective Suicide is one of the leading causes of death worldwide, yet clinicians find it difficult to reliably identify individuals at high risk for suicide. Algorithmic approaches for suicide risk detection have been developed in recent years, mostly based on data from electronic health records (EHRs). Significant room for improvement remains in...