Depressive self-focus bias following failure: an eye-tracking study among individuals with clinical depression.

Objective: Depression is often characterized by a persistent sense of failure. Cognitive theories of depression suggest that depressed individuals may exhibit a maladaptive cognitive style, characterized by increased self-focus following personal failure. The validity of this proposition, however, is yet to be fully examined. This study aimed to identify the relation between symptoms in major depressive disorder and increased self-focus in failure situations. Methods: This clinical study involved a cohort of 30 patients diagnosed with and treated for depression. We used an eye-tracking paradigm to observe and analyze gaze direction - indicative of either self-focus or self-avoidance - after remembering a significant failure event. Results: Contrary to the maladaptive cognitive style hypothesis, a majority of the depressed participants demonstrated an inclination towards self-avoidance following failure. Nevertheless, approximately 30% of the patient group - those with the highest scores of guilt, punishment, and self-blame - displayed a self-focused attentional bias post-failure. Conclusions: The presence of a maladaptive self-focusing style may be confined to severely depressed patients with high levels of guilt, punishment, and self-blame. These findings could have substantial clinical implications, as attention bias modification interventions could be particularly beneficial for this subgroup of patients.

Investigating brain structure and tDCS response in obsessive-compulsive disorder.

Obsessive-Compulsive Disorder (OCD) is characterized by intrusive thoughts and repetitive behaviors, with associated brain abnormalities in various regions. This study explores the correlation between neural biomarkers and the response to transcranial Direct Current Stimulation (tDCS) in OCD patients. Using structural MRI data from two tDCS trials involving 55 OCD patients and 28 controls, cortical thickness, and gray matter morphometry was analyzed. Findings revealed thicker precentral and paracentral areas in OCD patients, compared to control (p < 0.001). Correlations between cortical thickness and treatment response indicated a significant association between a thinner precentral area and reduced Yale-Brown Obsessive Compulsive Scale (YBOCS) scores (p = 0.02). While results highlight the complexity of treatment response predictors, this study sheds light on potential neural markers for tDCS response in OCD patients. Further investigations with larger datasets are warranted to better understand the underpinnings of these biomarkers and their implications for personalized treatment approaches.

Treating refractory obsessive compulsive disorder with cathodal transcranial direct current stimulation over the supplementary motor area: a large multisite randomized sham-controlled double-blind study.

Background: The present study evaluated the therapeutic efficacy and tolerability of 10 transcranial direct current stimulation (tDCS) sessions in treatment-resistance obsessive-compulsive disorder (OCD) patients using a multisite double-blind sham-controlled design. Methods: Eighty treatment-resistance outpatients suffering from obsessive-compulsive disorder were randomized to receive either active or sham transcranial direct current stimulation. The cathode was positioned over the supplementary motor area and the anode over the right supraorbital area. Patients were evaluated at baseline, end of treatment (day 14), one-month follow-up (day 45), and three-month follow-up (day 105) on the Yale-Brown Obsessive Compulsive Scale. Results: Although a significant interaction between time and treatment was observed, the primary endpoint-measuring the change in Yale-Brown obsessive compulsive scale scores after two weeks-was not achieved. Conversely, the secondary endpoint, which concerned the change in Yale-Brown obsessive compulsive scale scores after three months, was successfully met. It is important to note, however, that there were no significant differences in the percentage of responders and remitters at any of the post-treatment assessments. This suggests that the treatment may not have had a clinically relevant impact. Patients well received the transcranial direct current stimulation treatment, indicating its good tolerability. Conclusion: This is the largest controlled trial using transcranial direct current stimulation in treatment-resistance obsessive-compulsive disorder patients. Our results indicate the importance of studying the placebo effect in transcranial direct current stimulation and the necessity to consider a long follow-up time to best evaluate the effects of the intervention. Clinical trial registration: ClinicalTrials.gov, identifier NCT03304600.

Neurological soft signs as trait markers of a subset of patients with obsessive-compulsive disorder with low insight and altered cognitive abilities.

Neurological soft signs (NSS) are subtle motor control impairments that include involuntary movements and abnormalities of motor coordination, sensory integration and lateralization. They engage different brain networks, including the prefrontal networks that support the higher cognitive functions that are dysfunctional in obsessive-compulsive disorder (OCD). This study investigated the relationships between the presence of NSS and patients' severity of OCD symptoms, insight, and treatment resistance in a sample of 63 patients. Treatment-resistance was assessed considering all the treatments the patients received during the course of their disease. The four dimensions of OCD defined in the dimensional obsessive-compulsive scale were considered. Links between the patients' cognitive abilities and NSS were assessed using tests targeting specifically the core components of executive functions. As expected, OCD patients displayed more NSS than individually matched control participants. In OCD patients, high NSS scores were associated with poor insight and lower cognitive abilities. Multiple regression analysis identified worse visuospatial working memory, attentional control, and verbal fluency as predictive factors of high NSS scores among cognitive functions. Unexpectedly, the patients displaying symptoms in the contamination/washing dimension displayed less NSS than the other patients. In contrast, neither the severity of OCD symptoms nor long-range treatment resistance was significantly related to patients' NSS scores. Altogether, our findings suggest that high NSS scores may be a trait marker of a subset of OCD patients with low insight and particularly altered cognitive abilities who would not express the contamination/washing dimension of the pathology.

EEG microstate co-specificity in schizophrenia and obsessive-compulsive disorder.

The past 20 years of research on EEG microstates has yielded the hypothesis that the imbalance pattern in the temporal dynamics of microstates C (increased) and D (decreased) is specific to schizophrenia. A similar microstate imbalance has been recently found in obsessive-compulsive disorder (OCD). The aim of the present high-density EEG study was to examine whether this pathological microstate pattern is co-specific to schizophrenia and OCD. We compared microstate temporal dynamics using Bayesian analyses, transition probabilities analyses and the Topographic Electrophysiological State Source-Imaging method for source reconstruction in 24 OCD patients and 28 schizophrenia patients, respectively, free of comorbid psychotic and OCD symptoms, and 27 healthy controls. OCD and schizophrenia patients exhibited the same increased contribution of microstate C, decreased duration and contribution of microstate D and greater D → C transition probabilities, compared with controls. A Bayes factor of 4.424 for the contribution of microstate C, 4.600 and 3.824, respectively, for the duration and contribution of microstate D demonstrated that there was no difference in microstate patterns between the two disorders. Source reconstruction further showed undistinguishable dysregulations between the Salience Network (SN), associated with microstate C, and the Executive Control Network (ECN), associated with microstate D, and between the ECN and cognitive cortico-striato-thalamo-cortical (CSTC) loop in the two disorders. The ECN/CSTC loop dysconnectivity was slightly worsened in schizophrenia. Our findings provide substantial evidence for a common aetiological pathway in schizophrenia and OCD, i.e. microstate co-specificity, and same anomalies in salience and external attention processing, leading to co-expression of symptoms.

High treatment resistance is associated with lower performance in the Stroop test in patients with obsessive-compulsive disorder.

Around 50% of the patients with obsessive-compulsive disorder (OCD) are resistant to treatment, and patients with OCD show alterations in a broad range of cognitive abilities. The present study investigated the links between treatment-resistance, executive and working memory abilities, and the severity of OCD symptoms among 66 patients with OCD. The patients performed seven tests gauging their executive functions and working memory and filled in questionnaires for OCD severity and insight into their pathology. In addition, the executive and working memory abilities of a subset of these patients were compared with those of individually matched control participants. In contrast with previous studies, patients' treatment resistance was evaluated by considering the clinical outcomes of all the treatments that they received during the course of their disease. Higher treatment resistance was associated with lower performance in one particular executive test, the Stroop test, which assessed patients' ability to inhibit prepotent/automatic responses. Older age and more severe OCD symptoms were also associated with higher treatment resistance. Regardless of OCD severity, the patients displayed small to moderate deficits across most components of executive functions compared to control participants. Interestingly, patients with OCD took more time than control participants to perform speeded neuropsychological tests but never made more errors. Altogether, this study shows that the treatment-resistance of patients with OCD may be reliably quantified over the course of years and treatments using Pallanti and Quercioli's (2006) treatment resistance-related scales. The data suggest that the Stroop test could be used clinically to anticipate treatment outcomes in to-be-treated patients.

No mercy for victims: Exploring the link between dark personality traits, aggressive video game behavior, and severe traffic violations.

This study investigates the relationship between dark personality traits, aggressive behavior in violent video games, and severe traffic violations among 200 driving offenders from Tehran, Iran, participating in a rehabilitation program. Participants engaged in a computerized shooting decision task, where their tendency to shoot unarmed targets (innocent victims), compared to armed targets (criminals), was used as an indicator of aggressive behavior toward innocent victims. Additionally, they completed self-report measures of narcissism, Machiavellianism, psychopathy, and sadism to evaluate the impact of Dark Tetrad personality traits on their behavior. Bivariate analyses revealed associations between Dark Tetrad personality traits and aggressive behavior in the video game with serious traffic offenses. Multivariate analyses identified Machiavellianism, sadism, and aggressive behavior in video games as significant predictors of severe traffic offenses. The results suggest that dark personality traits and aggressive behavior in video games may aid in better identifying road traffic offenders with the most severe violations. Potential implications for preventing repeated traffic offenses by tailoring rehabilitation programs are discussed.

Microstates imbalance is associated with a functional dysregulation of the resting-state networks in obsessive-compulsive disorder: a high-density electrical neuroimaging study using the TESS method.

The dysfunctional patterns of microstates dynamics in obsessive-compulsive disorder (OCD) remain uncertain. Using high-density electrical neuroimaging (EEG) at rest, we explored microstates deterioration in OCD and whether abnormal microstates patterns are associated with a dysregulation of the resting-state networks interplay. We used EEG microstates analyses, TESS method for sources reconstruction, and General Linear Models to test for the effect of disease severity on neural responses. OCD patients exhibited an increased contribution and decreased duration of microstates C and D, respectively. Activity was decreased in the Salience Network (SN), associated with microstate C, but increased in the Default Mode Network (DMN) and Executive Control Network (ECN), respectively, associated with microstates E and D. The hyperactivity of the right angular gyrus in the ECN correlated with the symptoms severity. The imbalance between microstates C and D invalidates the hypothesis that this electrophysiological pattern is specific to psychosis. Demonstrating that the SN-ECN dysregulation manifests as abnormalities in microstates C and D, we confirm that the SN deterioration in OCD is accompanied by a failure of the DMN to deactivate and aberrant compensatory activation mechanisms in the ECN. These abnormalities explain typical OCD clinical features but also detachment from reality, shared with psychosis.

The priming effect of repetitive transcranial magnetic stimulation on clinical response to electroconvulsive therapy in treatment-resistant depression: a randomized, double-blind, sham-controlled study.

BACKGROUND: Electroconvulsive therapy (ECT) is one of the most effective treatments for treatment-resistant depression (TRD). However, due to response delay and cognitive impairment, ECT remains an imperfect treatment. Compared to ECT, repetitive transcranial magnetic stimulation (rTMS) is less effective at treating severe depression, but has the advantage of being quick, easy to use, and producing almost no side effects. In this study, our objective was to assess the priming effect of rTMS sessions before ECT on clinical response in patients with TRD. METHODS: In this multicenter, randomized, double-blind, sham-controlled trial, 56 patients with TRD were assigned to active or sham rTMS before ECT treatment. Five sessions of active/sham neuronavigated rTMS were administered over the left dorsolateral prefrontal cortex (20 Hz, 90% resting motor threshold, 20 2 s trains with 60-s intervals, 800 pulses/session) before ECT (which was active for all patients) started. Any relative improvements were then compared between both groups after five ECT sessions, in order to assess the early response to treatment. RESULTS: After ECT, the active rTMS group exhibited a significantly greater relative improvement than the sham group [43.4% (28.6%) v. 25.4% (17.2%)]. The responder rate in the active group was at least three times higher. Cognitive complaints, which were assessed using the Cognitive Failures Questionnaire, were higher in the sham rTMS group compared to the active rTMS group, but this difference was not corroborated by cognitive tests. CONCLUSIONS: rTMS could be used to enhance the efficacy of ECT in patients with TRD. ClinicalTrials.gov: NCT02830399.

Baseline Clinical and Neuroimaging Biomarkers of Treatment Response to High-Frequency rTMS Over the Left DLPFC for Resistant Depression.

Background: Repetitive transcranial magnetic stimulation (rTMS) has proven to be an efficient treatment option for patients with treatment-resistant depression (TRD). However, the success rate of this method is still low, and the treatment outcome is unpredictable. The objective of this study was to explore clinical and structural neuroimaging factors as potential biomarkers of the efficacy of high-frequency (HF) rTMS (20 Hz) over the left dorso-lateral pre-frontal cortex (DLPFC). Methods: We analyzed the records of 131 patients with mood disorders who were treated with rTMS and were assessed at baseline at the end of the stimulation and at 1 month after the end of the treatment. The response is defined as a 50% decrease in the MADRS score between the first and the last assessment. Each of these patients underwent a T1 MRI scan of the brain, which was subsequently segmented with FreeSurfer. Whole-brain analyses [Query, Design, Estimate, Contrast (QDEC)] were conducted and corrected for multiple comparisons. Additionally, the responder status was also analyzed using binomial multivariate regression models. The explored variables were clinical and anatomical features of the rTMS target obtained from T1 MRI: target-scalp distance, DLPFC gray matter thickness, and various cortical measures of interest previously studied. Results: The results of a binomial multivariate regression model indicated that depression type (p = 0.025), gender (p = 0.010), and the severity of depression (p = 0.027) were found to be associated with response to rTMS. Additionally, the resistance stage showed a significant trend (p = 0.055). Whole-brain analyses on volume revealed that the average volume of the left part of the superior frontal and the caudal middle frontal regions is associated with the response status. Other MRI-based measures are not significantly associated with response to rTMS in our population. Conclusion: In this study, we investigated the clinical and neuroimaging biomarkers associated with responsiveness to high-frequency rTMS over the left DLPFC in a large sample of patients with TRD. Women, patients with bipolar depressive disorder (BDD), and patients who are less resistant to HF rTMS respond better. Responders present a lower volume of the left part of the superior frontal gyrus and the caudal middle frontal gyrus. These findings support further investigation into the use of clinical variables and structural MRI as possible biomarkers of rTMS treatment response.

Preliminary Evidence That the Short Allele of 5-HTTLPR Moderates the Association of Psychiatric Symptom Severity on Suicide Attempt: The Example in Obsessive-Compulsive Disorder.

Background: The severity of symptoms represents an important source of distress in patients with a psychiatric disease. However, the extent to which this endogenous stress factor interacts with genetic vulnerability factors for predicting suicide risks remains unclear. Methods: We evaluated whether the severity of symptoms interacts with a genetic vulnerability factor (the serotonin transporter gene-linked promoter region variation) in predicting the frequency of lifetime suicide attempts in patients with a psychiatric disease. Symptom severity and 5-HTTLPR polymorphism were collected from a sample of 95 patients with obsessive-compulsive disorder (OCD). Lifetime suicide attempt was the primary outcome, and antecedent of multiple suicide attempts was the secondary outcome. Results: The gene-by-symptoms interaction was associated with an excess risk of suicide attempts (OR = 4.39, 95CI[1.44, 13.38], p < 0.009) and of multiple suicide attempts (OR = 4.18, 95CI[1.04, 16.77], p = 0.043). Symptom severity (moderate, severe, or extreme) was associated with an approximately five-fold increase in the odds of a lifetime suicide attempt in patients carrying one or two copies of the short allele of 5-HTTLPR. No such relationship was found for patients carrying the long allele. Conclusion: This study provides preliminary evidence for the gene-by-stress interaction on suicide attempt when stress is operationalized as symptom severity. Progress in suicide research may come from efforts to investigate the gene-by-symptoms interaction hypothesis in a variety of diseases.

How do they add up? The interaction between the placebo and treatment effect: A systematic review.

AIM: The placebo effect and the specific effect are often thought to add up (additive model). Whether additivity holds can dramatically influence the external validity of a trial. This assumption of additivity was tested by Kleijnen et al in 1994 but the data produced since then have not been synthetized. In this review, we aimed to systematically review the literature to determine whether additivity held. METHODS: We searched Medline and PsychInfo up to 10 January 2019. Studies using the balanced placebo design (BPD), testing two different strengths of placebos, were included. The presence of interaction was evaluated by comparing each group in the BPD with analysis of variance or covariance. RESULTS: Thirty studies were included and the overall risk of bias was high: four found evidence of additivity and 16 studies found evidence of interaction (seven had evidence of positive additivity). CONCLUSION: Evidence of additivity between placebo and specific features of treatments was rare in included studies. We suggest interventions for placebo-sensitive ailments should be tested in trials designed to take interactions seriously once an exploratory RCTs has proven their efficacy with sufficient internal validity.

Impact of brain-derived neurotrophic factor Val66Met polymorphism and response to escitalopram or paroxetine in obsessive-compulsive disorder.

OBJECTIVE: Obsessive-compulsive disorder (OCD) is a severe psychiatric disorder characterized by its heterogeneous nature and by different dimensions of obsessive-compulsive (OC) symptoms. Serotonin reuptake inhibitors (SRIs) are used to treat OCD, but up to 40% to 60% of patients do not show a significant improvement with these medications. In this study, we aimed to test the impact of brain-derived neurotrophic factor (BDNF) Val66Met polymorphism on the efficacy of antidepressants in OCD overall, and in relation to the different OC dimensions. METHODS: In a 6-month prospective treatment study, 69 Caucasian OCD patients were treated with escitalopram for 24 weeks or with escitalopram for 12 weeks followed by paroxetine for an additional 12-week period. Patients were genotyped and assessed for treatment response. The main clinical outcomes were improvement of the Yale-Brown Obsessive-Compulsive Scale score and in different OC symptom dimension scores. RESULTS: The Val/Val group comprised 43 (62%) patients, the Val/Met and Met/Met group comprised 26 (38%) patients. Forty-two patients were classified as responders at 12 weeks and 38 at 24 weeks; no significant association was found between BDNF Val66Met and SRIs response at 12 and 24 weeks. In analyses of the different OC symptom dimensions, the Met allele was associated with a slightly reduced score in the aggressive/checking dimension at 6 months (P = .048). CONCLUSIONS: Our findings do not support the usefulness of BDNF Val66Met genotyping to predict overall response to treatment with SRIs in OCD; they did however suggest a better outcome at 6 months for the aggressive/checking symptom dimension for patients carrying the Met allele.

Treating refractory obsessive-compulsive disorder with transcranial direct current stimulation: An open label study.

BACKGROUND: Obsessive-compulsive disorder (OCD) is a complex disorder with 40%-60% of patients' refractory to treatment. Transcranial direct current stimulation (tDCS) has been shown to induce potent and long-lasting effects on cortical excitability. The aim of the present clinical trial was to evaluate the therapeutic efficacy and tolerability of cathodal tDCS over the supplementary motor area (SMA) in treatment-resistant OCD patients. METHODS: Twenty-one treatment-resistant OCD outpatients received 10 sessions of tDCS. Each treatment session consisted of 2 mA stimuli for 30 min. The cathode was positioned over the bilateral SMA and the anode over the right supraorbital area. Patients were evaluated at baseline, end of treatment, one-month follow-up, and three-month follow-up. Response to treatment was defined as at least a decrease of 35% on the Yale-Brown Obsessive-Compulsive Scale (YBOCS) and a score of 2 or less on the Clinical Global Impressions-Improvement (CGI-I) between baseline and 1-month follow-up. RESULTS: There was a significant decrease of YBOCS scores between baseline and one-month assessment. At one month, five patients (24%) were considered as responders and 3 (15%) at 3 months. We also observed concomitant changes in depressive symptoms, and insight. The treatment was well tolerated. Short-lasting side effects were reported as localized tingling sensation and skin redness. CONCLUSION: Our results suggest that the use of cathodal tDCS over the SMA and anodal tDCS over the right supraorbital area in OCD treatment-refractory patients is safe and promising to improve obsessive and compulsive symptoms. Large randomized controlled trials are needed to confirm this positive result.

Predicting relapse in patients with severe alcohol use disorder: The role of alcohol insight and implicit alcohol associations.

Low insight is reported as a risk factor for relapse among patients treated for alcohol use disorders. However, to date, little is known on why patients with low insight are at higher risk for relapse. In this study, we tested the hypothesis that an implicit preference for alcohol over abstinence predicts relapse in patients with low, but not high, alcohol insight. Participants consisted of 77 patients who had received treatment for severe alcohol use disorder in a hospital in France. During hospitalization, they completed a self-report measure of insight and an implicit association test to assess implicit preference for alcohol over abstinence. The primary outcome was relapse assessed one month after discharge. Control variables were gender, age, cognitive deficit, anxiety, depression, craving, and impulsivity. Data were analysed using logistic regression analysis. After adjusting for demographic and clinical variables, relapse was predicted by the interaction between insight and implicit preference for alcohol but not by their main effects alone. Implicit preference for alcohol predicted relapse among patients with relatively low insight, but not among those with relatively high insight. These findings suggest that patients with low insight and strong implicit preference for alcohol are at a higher risk of relapse. Clinicians may therefore focus on and tailor specific interventions to prevent relapse in this vulnerable and at-risk population.

Forecasting a Fatal Decision: Direct Replication of the Predictive Validity of the Suicide-Implicit Association Test.

A previous study by Nock et al. (2010) suggested that people's implicit identification with "death" or "suicide" can accurately predict whether they will attempt suicide several months in advance. We report the first direct and independent replication of this promising finding. Participants were 165 patients seeking treatment at a psychiatric unit in France. At baseline, patients completed the Suicide-Implicit Association Test (S-IAT), a semistructured interview, and a self-report measure of suicide ideation. Six months later, we contacted participants by phone and examined their hospital medical records to determine whether they had made a new suicide attempt. Results showed that the S-IAT did not distinguish between patients who were admitted to the hospital following suicide attempts and those who were admitted for other reasons. As in the original study, however, the S-IAT predicted suicide attempts within the 6-month follow-up period beyond well-known predictors. The test correctly classified 85% of patients (95% confidence interval = [76.91, 91.53]), supporting its diagnostic value for identifying who will make a suicide attempt.

[Influence of post-traumatic stress disorder on asthma]. / Influence du trouble stress post-traumatique sur l'asthme.

INTRODUCTION: Exposure to a traumatic event may not only lead to a large variety of mental disorders, such as post-traumatic stress disorder (PTSD) but also respiratory symptoms and/or respiratory diseases, as asthma. OBJECTIVES: Systematic literature review of data on the impact of post-traumatic stress disorder on asthma. DOCUMENTARY SOURCES: Medline, on the period 1980-2018 with the following keywords: "PTSD" or "post-traumatic stress disorder" or "post-traumatic stress disorder" and "asthma", limits "title/abstract"; the selected languages were English or French. Among 141 articles, 23 abstracts have given use to a dual reading to select 14 studies. RESULTS: While PTSD may develop 4 weeks after being exposed to a traumatic event during which the physical integrity of the person has been threatened, it might also develop several months or years later. PTSD has been reported to be a risk factor for asthma and also a factor that might enhance a preexisting asthma. It is also important to note that this relation has been highlighted among several populations, traumatic events and regardless the gender and/or cultural factors. Despite its impact on the development of asthma, in asthmatic patients, PTSD may be responsible for poor asthma control, increased rates of healthcare use (visit in the emergency department and/or hospitalization for asthma) and poor asthma-related quality of life. The study of the association between PTSD and asthma have to take into account some potentially confounding factors, such as smoking status and dust exposure (e.g.: asthma following the terrorist attacks of the World Trade Center). Less is known regarding the potential mechanisms involved in the association between PTSD and asthma. Several factors including the nervous system, the hypothalamo-pituitary-adrenal axis, the inflammatory response and the immune system may explain the association. CONCLUSION: PTSD is a risk factor for the development of asthma and for the worsening of preexisting asthma. In asthmatic patients, it is of primary importance to systematically screen potential PTSD that might be developed after a traumatic event or a preexisting traumatic condition. Moreover, after exposure to a traumatic event, a special attention needs to be paid to somatic reactions such as asthma. The majority of studies having been conducted on American samples, replicating studies among European samples appears of prime importance in order to add a body of knowledge on the association between somatic and psychiatric conditions.

Mummy, daddy, and addiction: Implicit insecure attachment is associated with substance use in college students.

Indirect measures of cognition have become an important tool in research on addiction. To date, however, no research has examined whether indirect measures of parent attachment relate to substance use. To examine this issue, a sample of college students (N = 121) was asked to complete two measures of explicit attachment (the Relationship Questionnaire; Bartholomew & Horowitz, 1991, and the Adult Attachment Styles; Collins & Read, 1990), and a measure of implicit attachment (the Single Category Implicit Association Test, Karpinski & Steinman, 2006). The indirect attachment measure assessed the strength of automatic mental association between the concepts parents and secure. Participants also completed different measures of tobacco, cannabis, and alcohol use. Results showed that, for most of the participants, the parents were considered a source of security at both the explicit and implicit levels. Direct and indirect attachment measures were not related to each other. Overall, explicit attachment was not related to substance use. However, implicit attachment was significantly associated with the use of licit (tobacco) and illicit (cannabis) drugs. We also found some evidence that polydrug use is especially common among students with an insecure implicit attachment. This is the first study to examine how implicit attachment processes relate to addictive behaviors. The results suggest that implicit attachment, thought to reflect unconscious traces of past experiences, is a better predictor of substance use in college students than direct, self-reported measures of attachment. Further studies should examine whether implicit attachment is associated with severe substance use disorders in clinical populations. (PsycINFO Database Record (c) 2019 APA, all rights reserved).