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1.
Cogn Emot ; : 1-20, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38738654

ABSTRACT

Inhibition, an executive function, is critical for achieving goals that require suppressing unwanted behaviours, thoughts, or distractions. One hypothesis of the emotion and goal compatibility theory is that emotions of sadness and fear enhance inhibitory control. Across Experiments 1-4, we tested this hypothesis by inducing a happy, sad, fearful, and neutral emotional state prior to completing an inhibition task that indexed a specific facet of inhibition (oculomotor, resisting interference, behavioural, and cognitive). In Experiment 4, we included an anger induction to examine whether valence or motivational-orientation best-predicted performance. We found support that fear and sadness enhanced inhibition except when inhibition required resisting interference. We argue that sadness and fear enhance inhibitory control aiding the detection and analysis of problems (i.e. sadness) or threats (i.e. fear) within one's environment. In sum, this work highlights the importance of identifying how negative emotions can be beneficial for and interact with specific executive functions influencing down-stream processing including attention, cognition, and memory.

2.
J Psychiatry Neurosci ; 48(3): E217-E231, 2023.
Article in English | MEDLINE | ID: mdl-37339816

ABSTRACT

BACKGROUND: Decision-making under approach-avoidance conflict (AAC; e.g., sacrificing quality of life to avoid feared outcomes) may be affected in multiple psychiatric disorders. Recently, we used a computational (active inference) model to characterize information processing differences during AAC in individuals with depression, anxiety and/or substance use disorders. Individuals with psychiatric disorders exhibited increased decision uncertainty (DU) and reduced sensitivity to unpleasant stimuli. This preregistered study aimed to determine the replicability of this processing dysfunction. METHODS: A new sample of participants completed the AAC task. Individual-level computational parameter estimates, reflecting decision uncertainty and sensitivity to unpleasant stimuli ("emotion conflict"; EC), were obtained and compared between groups. Subsequent analyses combining the prior and current samples allowed assessment of narrower disorder categories. RESULTS: The sample in the present study included 480 participants: 97 healthy controls, 175 individuals with substance use disorders and 208 individuals with depression and/or anxiety disorders. Individuals with substance use disorders showed higher DU and lower EC values than healthy controls. The EC values were lower in females, but not males, with depression and/or anxiety disorders than in healthy controls. However, the previously observed difference in DU between participants with depression and/or anxiety disorders and healthy controls did not replicate. Analyses of specific disorders in the combined samples indicated that effects were common across different substance use disorders and affective disorders. LIMITATIONS: There were differences, although with small effect size, in age and baseline intellectual functioning between the previous and current sample, which may have affected replication of DU differences in participants with depression and/or anxiety disorders. CONCLUSION: The now robust evidence base for these clinical group differences motivates specific questions that should be addressed in future research: can DU and EC become behavioural treatment targets, and can we identify neural substrates of DU and EC that could be used to measure severity of dysfunction or as neuromodulatory treatment targets?


Subject(s)
Depression , Substance-Related Disorders , Female , Humans , Uncertainty , Depression/therapy , Quality of Life , Anxiety Disorders/psychology , Anxiety , Substance-Related Disorders/psychology
3.
Psychother Psychosom ; 92(2): 87-100, 2023.
Article in English | MEDLINE | ID: mdl-36630946

ABSTRACT

INTRODUCTION: Repetitive negative thinking (RNT) is a cognitive process focusing on self-relevant and negative experiences, leading to a poor prognosis of major depressive disorder (MDD). We previously identified that connectivity between the precuneus/posterior cingulate cortex (PCC) and right temporoparietal junction (rTPJ) was positively correlated with levels of RNT. OBJECTIVE: In this double-blind, randomized, sham-controlled, proof-of-concept trial, we employed real-time functional magnetic resonance imaging neurofeedback (rtfMRI-nf) to delineate the neural processes that may be causally linked to RNT and could potentially become treatment targets for MDD. METHODS: MDD-affected individuals were assigned to either active (n = 20) or sham feedback group (n = 19). RNT was measured by the Ruminative Response Scale-brooding subscale (RRS-B) before and 1 week after the intervention. RESULTS: Individuals in the active but not in the sham group showed a significant reduction in the RRS-B; however, a greater reduction in the PCC-rTPJ connectivity was unrelated to a greater reduction in the RRS-B. Exploratory analyses revealed that a greater reduction in the retrosplenial cortex (RSC)-rTPJ connectivity yielded a more pronounced reduction in the RRS-B in the active but not in the sham group. CONCLUSIONS: RtfMRI-nf was effective in reducing RNT. Considering the underlying mechanism of rtfMIR-nf, the RSC and rTPJ could be part of a network (i.e., default mode network) that might collectively affect the intensity of RNT. Understanding the relationship between the functional organization of targeted neural changes and clinical metrics, such as RNT, has the potential to guide the development of mechanism-based treatment of MDD.


Subject(s)
Depressive Disorder, Major , Neurofeedback , Pessimism , Humans , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/therapy , Neurofeedback/methods , Depression , Magnetic Resonance Imaging/methods
4.
Cogn Affect Behav Neurosci ; 22(4): 849-867, 2022 08.
Article in English | MEDLINE | ID: mdl-35292905

ABSTRACT

Mindfulness training (MT) promotes the development of one's ability to observe and attend to internal and external experiences with objectivity and nonjudgment with evidence to improve psychological well-being. Real-time functional MRI neurofeedback (rtfMRI-nf) is a noninvasive method of modulating activity of a brain region or circuit. The posterior cingulate cortex (PCC) has been hypothesized to be an important hub instantiating a mindful state. This nonrandomized, single-arm study examined the feasibility and tolerability of training typically developing adolescents to self-regulate the posterior cingulate cortex (PCC) using rtfMRI-nf during MT. Thirty-four adolescents (mean age: 15 years; 14 females) completed the neurofeedback augmented mindfulness training task, including Focus-on-Breath (MT), Describe (self-referential thinking), and Rest conditions, across three neurofeedback and two non-neurofeedback runs (Observe, Transfer). Self-report assessments demonstrated the feasibility and tolerability of the task. Neurofeedback runs differed significantly from non-neurofeedback runs for the Focus-on-Breath versus Describe contrast, characterized by decreased activity in the PCC during the Focus-on-Breath condition (z = -2.38 to -6.27). MT neurofeedback neural representation further involved the medial prefrontal cortex, anterior cingulate cortex, dorsolateral prefrontal cortex, posterior insula, hippocampus, and amygdala. State awareness of physical sensations increased following rtfMRI-nf and was maintained at 1-week follow-up (Cohens' d = 0.69). Findings demonstrate feasibility and tolerability of rtfMRI-nf in healthy adolescents, replicates the role of PCC in MT, and demonstrate a potential neuromodulatory mechanism to leverage and streamline the learning of mindfulness practice. ( ClinicalTrials.gov identifier #NCT04053582; August 12, 2019).


Subject(s)
Mindfulness , Self-Control , Adolescent , Feasibility Studies , Female , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging/methods
5.
Neuroimage ; 230: 117796, 2021 04 15.
Article in English | MEDLINE | ID: mdl-33503481

ABSTRACT

BACKGROUND: The Monetary Incentive Delay task (MID) has been used extensively to probe anticipatory reward processes. However, individual differences evident during this task may relate to other constructs such as general arousal or valence processing (i.e., anticipation of negative versus positive outcomes). This investigation used a latent variable approach to parse activation patterns during the MID within a transdiagnostic clinical sample. METHODS: Participants were drawn from the first 500 individuals recruited for the Tulsa-1000 (T1000), a naturalistic longitudinal study of 1000 participants aged 18-55 (n = 476 with MID data). We employed a multiview latent analysis method, group factor analysis, to characterize factors within and across variable sets consisting of: (1) region of interest (ROI)-based blood oxygenation level-dependent (BOLD) contrasts during reward and loss anticipation; and (2) self-report measures of positive and negative valence and related constructs. RESULTS: Three factors comprised of ROI indicators emerged to accounted for >43% of variance and loaded on variables representing: (1) general arousal or general activation; (2) valence, with dissociable responses to anticipation of win versus loss; and (3) region-specific activation, with dissociable activation in salience versus perceptual brain networks. Two additional factors were comprised of self-report variables, which appeared to represent arousal and valence. CONCLUSIONS: Results indicate that multiview techniques to identify latent variables offer a novel approach for differentiating brain activation patterns during task engagement. Such approaches may offer insight into neural processing patterns through dimension reduction, be useful for probing individual differences, and aid in the development of optimal explanatory or predictive frameworks.


Subject(s)
Anticipation, Psychological/physiology , Brain/diagnostic imaging , Brain/metabolism , Motivation/physiology , Reward , Adolescent , Adult , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Neuroimaging/methods , Oxygen Consumption/physiology , Young Adult
6.
Brain Behav Immun ; 93: 214-225, 2021 03.
Article in English | MEDLINE | ID: mdl-33508469

ABSTRACT

BACKGROUND: Major depressive disorder (MDD) is the leading cause of years lived with disability worldwide, and up to 40% of individuals with MDD do not respond to current treatments. Studies suggest that peripheral inflammation plays an important role in the striatal mesolimbic dopamine pathway and corticostriatal reward circuitry in MDD. Although MDD patients show blunted striatal responses to reward, the link between degree of inflammation and attenuation of reward processing is unclear. We investigated whether MDD patients with elevated peripheral inflammation exhibit attenuated reward responses to enhance our understanding of MDD pathophysiology and develop more effective treatments for current non-responders. METHODS: MDD subjects varying on serum C-reactive protein (CRP) concentrations (MDD-High CRP, >3 mg/L, n = 44; MDD-Low CRP, <3 mg/L, n = 44) and healthy comparisons (HC, n = 44) completed a monetary incentive delay (MID) task and provided blood samples to measure inflammation-related markers. MDD-High and MDD-Low were propensity score-matched on age, sex, body mass index (BMI), smoking status, exercise and MID task head motion. Percent change in blood oxygen level-dependent (BOLD) signal during anticipation of wins and losses was extracted from bilateral nucleus accumbens, dorsal caudate and dorsolateral putamen regions of interest (ROIs). A linear mixed-effects model was used to test group (MDD-High, MDD-Low and HC), condition (large-win, small-win and no win), and their interaction for these ROIs as well as whole-brain voxelwise data. Analyses also tested group differences in inflammatory mediators. Correlations were used to explore the relationship between inflammatory mediators and brain regions showing differences between MDD-High and MDD-Low. RESULTS: MDD-High exhibited: (a) lower BOLD signal change in dorsal caudate, thalamus, left insula and left precuneus during anticipation of small wins than MDD-Low; and (b) higher serum soluble intercellular adhesion molecule 1 (sICAM-1) and interleukin 6 (IL-6) concentrations than MDD-Low and HC. MDD as a whole, regardless of CRP-based inflammation, exhibited: (a) lower precuneus BOLD signal change to large wins than HC; and (b) higher Interleukin 1 receptor antagonist (IL-1ra), macrophage-derived chemokine (MDC) and macrophage inflammatory protein-1 alpha (MIP-1α) concentrations than HC. Higher serum sICAM-1 concentrations were associated with lower caudate BOLD signal change to small wins only within the MDD-High group. CONCLUSION: Within MDD patients, high inflammation (CRP, sICAM-1) was linked to reduced striatal activation recruited to discriminate intermediate reward magnitudes. These findings support an association between levels of peripheral inflammation and the degree of reward-related activation in individuals with MDD. REGISTRATION OF CLINICAL TRIALS: The ClinicalTrials.gov identifier for the clinical protocol associated with data published in this current paper is NCT02450240, "Latent Structure of Multi-level Assessments and Predictors of Outcomes in Psychiatric Disorders."


Subject(s)
Depressive Disorder, Major , Corpus Striatum , Humans , Inflammation , Magnetic Resonance Imaging , Motivation , Reward
7.
J Psychiatry Neurosci ; 46(1): E74-E87, 2021 01 04.
Article in English | MEDLINE | ID: mdl-33119490

ABSTRACT

BACKGROUND: Imbalances in approach-avoidance conflict (AAC) decision-making (e.g., sacrificing rewards to avoid negative outcomes) are considered central to multiple psychiatric disorders. We used computational modelling to examine 2 factors that are often not distinguished in descriptive analyses of AAC: decision uncertainty and sensitivity to negative outcomes versus rewards (emotional conflict). METHODS: A previously validated AAC task was completed by 478 participants, including healthy controls (n = 59), people with substance use disorders (n = 159) and people with depression and/or anxiety disorders who did not have substance use disorders (n = 260). Using an active inference model, we estimated individual-level values for a model parameter that reflected decision uncertainty and another that reflected emotional conflict. We also repeated analyses in a subsample (59 healthy controls, 161 people with depression and/or anxiety disorders, 56 people with substance use disorders) that was propensity-matched for age and general intelligence. RESULTS: The model showed high accuracy (72%). As further validation, parameters correlated with reaction times and self-reported task motivations in expected directions. The emotional conflict parameter further correlated with self-reported anxiety during the task (r = 0.32, p < 0.001), and the decision uncertainty parameter correlated with self-reported difficulty making decisions (r = 0.45, p < 0.001). Compared to healthy controls, people with depression and/or anxiety disorders and people with substance use disorders showed higher decision uncertainty in the propensity-matched sample (t = 2.16, p = 0.03, and t = 2.88, p = 0.005, respectively), with analogous results in the full sample; people with substance use disorders also showed lower emotional conflict in the full sample (t = 3.17, p = 0.002). LIMITATIONS: This study was limited by heterogeneity of the clinical sample and an inability to examine learning. CONCLUSION: These results suggest that reduced confidence in how to act, rather than increased emotional conflict, may explain maladaptive approach-avoidance behaviours in people with psychiatric disorders.


Subject(s)
Anxiety Disorders/physiopathology , Conflict, Psychological , Decision Making/physiology , Depressive Disorder/physiopathology , Psychomotor Performance/physiology , Reward , Substance-Related Disorders/physiopathology , Uncertainty , Adult , Affect/physiology , Auditory Perception/physiology , Avoidance Learning/physiology , Female , Humans , Longitudinal Studies , Male , Middle Aged , Models, Theoretical , Pattern Recognition, Visual/physiology , Young Adult
8.
PLoS Comput Biol ; 16(12): e1008484, 2020 12.
Article in English | MEDLINE | ID: mdl-33315893

ABSTRACT

Recent neurocomputational theories have hypothesized that abnormalities in prior beliefs and/or the precision-weighting of afferent interoceptive signals may facilitate the transdiagnostic emergence of psychopathology. Specifically, it has been suggested that, in certain psychiatric disorders, interoceptive processing mechanisms either over-weight prior beliefs or under-weight signals from the viscera (or both), leading to a failure to accurately update beliefs about the body. However, this has not been directly tested empirically. To evaluate the potential roles of prior beliefs and interoceptive precision in this context, we fit a Bayesian computational model to behavior in a transdiagnostic patient sample during an interoceptive awareness (heartbeat tapping) task. Modelling revealed that, during an interoceptive perturbation condition (inspiratory breath-holding during heartbeat tapping), healthy individuals (N = 52) assigned greater precision to ascending cardiac signals than individuals with symptoms of anxiety (N = 15), depression (N = 69), co-morbid depression/anxiety (N = 153), substance use disorders (N = 131), and eating disorders (N = 14)-who failed to increase their precision estimates from resting levels. In contrast, we did not find strong evidence for differences in prior beliefs. These results provide the first empirical computational modeling evidence of a selective dysfunction in adaptive interoceptive processing in psychiatric conditions, and lay the groundwork for future studies examining how reduced interoceptive precision influences visceral regulation and interoceptively-guided decision-making.


Subject(s)
Anxiety/physiopathology , Bayes Theorem , Computer Simulation , Depression/physiopathology , Feeding and Eating Disorders/physiopathology , Substance-Related Disorders/physiopathology , Adolescent , Adult , Case-Control Studies , Female , Heart Rate/physiology , Humans , Male , Middle Aged , Overweight/physiopathology , Thinness/physiopathology , Young Adult
9.
Hum Brain Mapp ; 41(2): 342-352, 2020 02 01.
Article in English | MEDLINE | ID: mdl-31633257

ABSTRACT

The ventromedial prefrontal cortex (vmPFC) is involved in regulation of negative emotion and decision-making, emotional and behavioral control, and active resilient coping. This pilot study examined the feasibility of training healthy subjects (n = 27) to self-regulate the vmPFC activity using a real-time functional magnetic resonance imaging neurofeedback (rtfMRI-nf). Participants in the experimental group (EG, n = 18) were provided with an ongoing vmPFC hemodynamic activity (rtfMRI-nf signal represented as variable-height bar). Individuals were instructed to raise the bar by self-relevant value-based thinking. Participants in the control group (CG, n = 9) performed the same task; however, they were provided with computer-generated sham neurofeedback signal. Results demonstrate that (a) both the CG and the EG show a higher vmPFC fMRI signal at the baseline than during neurofeedback training; (b) no significant positive training effect was seen in the vmPFC across neurofeedback runs; however, the medial prefrontal cortex, middle temporal gyri, inferior frontal gyri, and precuneus showed significant decreasing trends across the training runs only for the EG; (c) the vmPFC rtfMRI-nf signal associated with the fMRI signal across the default mode network (DMN). These findings suggest that it may be difficult to modulate a single DMN region without affecting other DMN regions. Observed decreased vmPFC activity during the neurofeedback task could be due to interference from the fMRI signal within other DMN network regions, as well as interaction with task-positive networks. Even though participants in the EG did not show significant positive increase in the vmPFC activity among neurofeedback runs, they were able to learn to accommodate the demand of self-regulation task to maintain the vmPFC activity with the help of a neurofeedback signal.


Subject(s)
Cerebral Cortex/physiology , Default Mode Network/physiology , Functional Neuroimaging , Neurofeedback/physiology , Prefrontal Cortex/physiology , Self-Control , Adult , Cerebral Cortex/diagnostic imaging , Default Mode Network/diagnostic imaging , Feasibility Studies , Female , Humans , Magnetic Resonance Imaging , Male , Pilot Projects , Prefrontal Cortex/diagnostic imaging
10.
Addict Biol ; 25(6): e12831, 2020 11.
Article in English | MEDLINE | ID: mdl-31617639

ABSTRACT

Blunted anterior insula activation during interoceptive perturbations has been associated with stimulant (cocaine and amphetamine) use disorder (SUD) and is related to risk for and prognosis of SUD. However, little is known whether these interoceptive alterations extend to opioid use disorder (OUD). This exploratory study used the same experimental probe during functional magnetic resonance imaging (fMRI) to test the hypothesis that SUD and OUD exhibit interoceptive discrepancies characterized by subjective ratings and activation within the insula. Recently, abstinent individuals diagnosed with current SUD (n = 40) or current OUD (n = 20) were compared with healthy individuals (CTL; n = 30) on brain and self-report responses during an interoceptive attention task known to elicit insula activation. Participants selectively attended to interoceptive (heartbeat and stomach) and exteroceptive signals during blood-oxygen-level-dependent fMRI recording. Groups and conditions were compared on (a) activation within probabilistic cytoarchitectonic segmentations of the insula and (b) self-reported stimulus intensity. First, SUD showed amplified ratings of heart-related sensations but attenuation of dorsal dysgranular insula activity relative to CTL. Amplified ratings were linked to drug use recency, while attenuation was normalized with greater past-year stimulant use. Second, SUD and OUD showed attenuation of dorsal dysgranular insula activity during attention to stomach sensations relative to CTL. Taken together, these results are consistent with altered neural processing of interoceptive signals in drug addiction, particularly as a function of SUD. Future studies will need to determine whether interoceptive metrics help to explain substance use disorder pathophysiology and are useful for predicting outcomes.


Subject(s)
Amphetamine-Related Disorders/physiopathology , Attention , Cerebral Cortex/physiopathology , Cocaine-Related Disorders/physiopathology , Interoception , Opioid-Related Disorders/physiopathology , Adult , Cerebral Cortex/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Young Adult
11.
J Int Neuropsychol Soc ; 24(9): 928-938, 2018 10.
Article in English | MEDLINE | ID: mdl-30375314

ABSTRACT

OBJECTIVES: To examine academic performance in dystrophinopathy as a function of dystrophin gene mutation position as well as intellectual function, executive skills, socioeconomic status (SES), behavior, and physical ability. METHODS: In a cross-sectional study, boys with dystrophinopathy (ages 5-17; n=50) completed tests of academics (Woodcock-Johnson-III: spelling, reading, calculation and total scores), executive functioning (selective attention/inhibitory control, set shifting, working memory, and processing speed), single word comprehension and nonverbal reasoning. Motor skills were assessed and parents provided demographic information and child behavioral assessments. Dystrophin gene mutation positions were dichotomized into groups (upstream versus downstream of exon 43, location of isoforms previously linked to intellectual impairment). Genetic mutation groups were compared on measures of academic achievement, and multiple regression analyses examined unique and joint contributions of executive skills, intelligence quotient (IQ), SES, motor abilities, behavior, and mutation positions to academic outcomes. RESULTS: Academic performance was slightly, yet significantly, lower than IQ and varied as a function of dystrophin gene position, wherein boys possessing the downstream mutation exhibited greater impairment than boys with the upstream mutation. Digit span forward (indexing verbal span), but no other measure of executive function, contributed significant variance to total academic achievement, spelling and calculation. CONCLUSIONS: Weak academic performance is associated with dystrophinopathy and is more common in downstream mutations. A specific deficit in verbal span may underlie inefficiencies observed in children with dystrophinopathy and may drive deficits impacting academic abilities. (JINS, 2018, 24, 928-938).


Subject(s)
Dystrophin/genetics , Educational Status , Executive Function , Academic Success , Adolescent , Behavior , Child , Child, Preschool , Comprehension , Cross-Sectional Studies , Humans , Intelligence Tests , Male , Memory, Short-Term , Mutation , Psychomotor Performance , Social Class
12.
Brain ; 138(Pt 11): 3413-26, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26336910

ABSTRACT

Bayesian ideal observer models quantify individuals' context- and experience-dependent beliefs and expectations about their environment, which provides a powerful approach (i) to link basic behavioural mechanisms to neural processing; and (ii) to generate clinical predictors for patient populations. Here, we focus on (ii) and determine whether individual differences in the neural representation of the need to stop in an inhibitory task can predict the development of problem use (i.e. abuse or dependence) in individuals experimenting with stimulants. One hundred and fifty-seven non-dependent occasional stimulant users, aged 18-24, completed a stop-signal task while undergoing functional magnetic resonance imaging. These individuals were prospectively followed for 3 years and evaluated for stimulant use and abuse/dependence symptoms. At follow-up, 38 occasional stimulant users met criteria for a stimulant use disorder (problem stimulant users), while 50 had discontinued use (desisted stimulant users). We found that those individuals who showed greater neural responses associated with Bayesian prediction errors, i.e. the difference between actual and expected need to stop on a given trial, in right medial prefrontal cortex/anterior cingulate cortex, caudate, anterior insula, and thalamus were more likely to exhibit problem use 3 years later. Importantly, these computationally based neural predictors outperformed clinical measures and non-model based neural variables in predicting clinical status. In conclusion, young adults who show exaggerated brain processing underlying whether to 'stop' or to 'go' are more likely to develop stimulant abuse. Thus, Bayesian cognitive models provide both a computational explanation and potential predictive biomarkers of belief processing deficits in individuals at risk for stimulant addiction.


Subject(s)
Amphetamine-Related Disorders/physiopathology , Brain/physiopathology , Cocaine-Related Disorders/physiopathology , Inhibition, Psychological , Neural Inhibition , Adolescent , Adult , Bayes Theorem , Caudate Nucleus/physiopathology , Central Nervous System Stimulants , Cerebral Cortex/physiopathology , Cohort Studies , Female , Functional Neuroimaging , Gyrus Cinguli/physiopathology , Humans , Logistic Models , Longitudinal Studies , Magnetic Resonance Imaging , Male , Marijuana Smoking , Prefrontal Cortex/physiopathology , Prospective Studies , Substance-Related Disorders/physiopathology , Thalamus/physiopathology , Young Adult
13.
J Neurosci ; 34(13): 4567-80, 2014 Mar 26.
Article in English | MEDLINE | ID: mdl-24672002

ABSTRACT

Identification of neurocognitive predictors of substance dependence is an important step in developing approaches to prevent addiction. Given evidence of inhibitory control deficits in substance abusers (Monterosso et al., 2005; Fu et al., 2008; Lawrence et al., 2009; Tabibnia et al., 2011), we examined neural processing characteristics in human occasional stimulant users (OSU), a population at risk for dependence. A total of 158 nondependent OSU and 47 stimulant-naive control subjects (CS) were recruited and completed a stop signal task while undergoing functional magnetic resonance imaging (fMRI). A Bayesian ideal observer model was used to predict probabilistic expectations of inhibitory demand, P(stop), on a trial-to-trial basis, based on experienced trial history. Compared with CS, OSU showed attenuated neural activation related to P(stop) magnitude in several areas, including left prefrontal cortex and left caudate. OSU also showed reduced neural activation in the dorsal anterior cingulate cortex (dACC) and right insula in response to an unsigned Bayesian prediction error representing the discrepancy between stimulus outcome and the predicted probability of a stop trial. These results indicate that, despite minimal overt behavioral manifestations, OSU use fewer brain processing resources to predict and update the need for response inhibition, processes that are critical for adjusting and optimizing behavioral performance, which may provide a biomarker for the development of substance dependence.


Subject(s)
Brain Mapping , Brain/physiopathology , Inhibition, Psychological , Substance-Related Disorders/pathology , Bayes Theorem , Brain/blood supply , Choice Behavior , Female , Humans , Image Processing, Computer-Assisted , Linear Models , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Oxygen/blood , Reaction Time/physiology , Risk , Substance-Related Disorders/physiopathology , Young Adult
14.
J Nurs Scholarsh ; 46(1): 11-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24119253

ABSTRACT

PURPOSE: Nonventilator hospital-acquired pneumonia (NV-HAP) is an underreported and unstudied disease, with potential for measurable outcomes, fiscal savings, and improvement in quality of life. The purpose of our study was to (a) identify the incidence of NV-HAP in a convenience sample of U.S. hospitals and (b) determine the effectiveness of reliably delivered basic oral nursing care in reducing NV-HAP. DESIGN: A descriptive, quasi-experimental study using retrospective comparative outcomes to determine (a) the incidence of NV-HAP and (b) the effectiveness of enhanced basic oral nursing care versus usual care to prevent NV-HAP after introduction of a basic oral nursing care initiative. METHODS: We used the International Statistical Classification of Diseases and Related Problems (ICD-9) codes for pneumonia not present on admission and verified NV-HAP diagnosis using the U.S. Centers for Disease Control and Prevention diagnostic criteria. We completed an evidence-based gap analysis and designed a site-specific oral care initiative designed to reduce NV-HAP. The intervention process was guided by the Influencer Model (see Figure) and participatory action research. FINDINGS: We found a substantial amount of unreported NV-HAP. After we initiated our oral care protocols, the rate of NV-HAP per 100 patient days decreased from 0.49 to 0.3 (38.8%). The overall number of cases of NV-HAP was reduced by 37% during the 12-month intervention period. The avoidance of NV-HAP cases resulted in an estimated 8 lives saved, $1.72 million cost avoided, and 500 extra hospital days averted. The extra cost for therapeutic oral care equipment was $117,600 during the 12-month intervention period. Cost savings resulting from avoided NV-HAP was $1.72 million. Return on investment for the organization was $1.6 million in avoided costs. CONCLUSIONS: NV-HAP should be elevated to the same level of concern, attention, and effort as prevention of ventilator-associated pneumonia in hospitals. CLINICAL RELEVANCE: Nursing needs to lead the way in the design and implementation of policies that allow for adequate time, proper oral care supplies, ease of access to supplies, clear procedures, and outcome monitoring ensuring that patients are protected from NV-HAP.


Subject(s)
Cross Infection/prevention & control , Oral Hygiene/nursing , Pneumonia/prevention & control , Adult , Cross Infection/epidemiology , Humans , Incidence , Nursing Care/methods , Nursing Evaluation Research , Nursing Methodology Research , Pneumonia/epidemiology , Retrospective Studies , Risk Factors , United States/epidemiology
15.
J Psychopharmacol ; 38(3): 236-246, 2024 03.
Article in English | MEDLINE | ID: mdl-38279659

ABSTRACT

BACKGROUND: Dysregulated ventral striatum function has been proposed as one important process occurring in individuals with substance use disorder. This study investigates the role of altered reward and loss anticipation, which is an important component of impaired decision-making, impulsivity, and vulnerability to relapse in individuals with amphetamine use disorder (AMP). AIMS: To determine whether AMP is associated with blunted striatum, prefrontal cortex, and insula signals during win and loss anticipation. METHODS: Participants with and without AMP (AMP+ n = 46, AMP- n = 90) from the Tulsa 1000 study completed a monetary incentive delay (MID) task during functional magnetic resonance imaging. RESULTS: Group main effects indicated that: (1) AMP+ exhibited lower bilateral caudate/putamen and left nucleus accumbens signal than AMP- across anticipation of wins and losses; and (2) AMP+ showed slower reaction times than AMP- during loss anticipation. Group*condition interactions demonstrated that AMP+ exhibited greater right amygdala signal than AMP- while anticipating large wins, a pattern that reversed when anticipating small losses. Left caudate/putamen attenuations in AMP+ during small loss anticipation were also evident. Groups did not differ in prefrontal or insula signals. CONCLUSIONS: AMP+ individuals have altered neural processing and response patterns during reward and loss anticipation, potentially reflecting impairments in dopamine function, which may influence their decision-making and reactions to different win/loss scenarios. These findings help to explain why AMP+ have difficulty with decision-making and exhibit a heightened focus on immediate rewards or punishments.


Subject(s)
Substance-Related Disorders , Ventral Striatum , Humans , Reward , Motivation , Magnetic Resonance Imaging , Ventral Striatum/diagnostic imaging , Amphetamines
16.
Drug Alcohol Depend ; 260: 111323, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38733735

ABSTRACT

BACKGROUND: Inflammatory biomarkers may differentiate clinical disorders, which could lead to more targeted interventions. Analyses within a clinical sample (May et al., 2021) revealed that females with substance use disorders (SUD) exhibited lower C-reactive protein (CRP) and higher interleukin (IL)-8 and -10 concentrations than females without SUD who met criteria for mood/anxiety disorders. We aimed to replicate these findings in a new sample. METHODS: Hypotheses and analyses were preregistered. Treatment-seeking individuals with mood/anxiety disorders and/or SUD (N = 184) completed a blood draw, clinical interview, and questionnaires. Participants were categorized as SUD+ (45F, 43M) and SUD- (78F, 18M). Principal component analysis (PCA) of questionnaire data resulted in two factors reflecting appetitive and aversive emotional states. SUD group and nuisance covariates (PCA factors, age, body mass index [BMI], medication, nicotine [and hormones in females]) predicted biomarker concentrations (CRP, IL-8, and IL-10) in regressions. RESULTS: In females, the omnibus CRP model [F(8, 114) = 8.02, p <.001, R²-adjusted =.32] indicated that SUD+ exhibited lower CRP concentrations than SUD- (ß = -.33, t = -3.09, p =.002, 95% CI [-.54, -.12]) and greater BMI was associated with higher CRP levels (ß =.58, t = 7.17, p <.001, 95% CI [.42,.74]). SUD+ exhibited higher IL-8 levels than SUD- in simple but not omnibus regression models. CONCLUSION: Findings across two samples bolster confidence that females with SUD show attenuated CRP-indexed inflammation. As SUD+ comorbidity was high, replication is warranted with respect to specific SUD classes (i.e., stimulants versus cannabis).


Subject(s)
Biomarkers , C-Reactive Protein , Substance-Related Disorders , Humans , Female , C-Reactive Protein/metabolism , Adult , Substance-Related Disorders/blood , Male , Biomarkers/blood , Middle Aged , Interleukin-8/blood , Interleukin-10/blood , Mood Disorders/blood , Mood Disorders/epidemiology , Anxiety Disorders/blood , Young Adult
17.
Neuropsychopharmacology ; 49(8): 1246-1254, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38291167

ABSTRACT

Hyperarousal symptoms in generalized anxiety disorder (GAD) are often incongruent with the observed physiological state, suggesting that abnormal processing of interoceptive signals is a characteristic feature of the disorder. To examine the neural mechanisms underlying interoceptive dysfunction in GAD, we evaluated whether adrenergic modulation of cardiovascular signaling differentially affects the heartbeat-evoked potential (HEP), an electrophysiological marker of cardiac interoception, during concurrent electroencephalogram and functional magnetic resonance imaging (EEG-fMRI) scanning. Intravenous infusions of the peripheral adrenergic agonist isoproterenol (0.5 and 2.0 micrograms, µg) were administered in a randomized, double-blinded and placebo-controlled fashion to dynamically perturb the cardiovascular system while recording the associated EEG-fMRI responses. During the 0.5 µg isoproterenol infusion, the GAD group (n = 24) exhibited significantly larger changes in HEP amplitude in an opposite direction than the healthy comparison (HC) group (n = 24). In addition, the GAD group showed significantly larger absolute HEP amplitudes than the HC group during saline infusions, when cardiovascular tone did not increase. No significant group differences in HEP amplitude were identified during the 2.0 µg isoproterenol infusion. Using analyzable blood oxygenation level-dependent fMRI data from participants with concurrent EEG-fMRI data (21 GAD and 21 HC), we found that the aforementioned HEP effects were uncorrelated with fMRI signals in the insula, ventromedial prefrontal cortex, dorsal anterior cingulate cortex, amygdala, and somatosensory cortex, brain regions implicated in cardiac signal processing in prior fMRI studies. These findings provide additional evidence of dysfunctional cardiac interoception in GAD and identify neural processes at the electrophysiological level that may be independent from blood oxygen level-dependent responses during peripheral adrenergic stimulation.


Subject(s)
Anxiety Disorders , Electroencephalography , Heart Rate , Isoproterenol , Magnetic Resonance Imaging , Humans , Male , Female , Adult , Anxiety Disorders/physiopathology , Heart Rate/drug effects , Heart Rate/physiology , Double-Blind Method , Isoproterenol/pharmacology , Isoproterenol/administration & dosage , Young Adult , Brain/physiopathology , Brain/drug effects , Brain/diagnostic imaging , Evoked Potentials/drug effects , Evoked Potentials/physiology , Interoception/physiology , Interoception/drug effects , Adrenergic beta-Agonists/administration & dosage , Adrenergic beta-Agonists/pharmacology
18.
Biol Psychol ; 191: 108825, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38823571

ABSTRACT

Recent Bayesian theories of interoception suggest that perception of bodily states rests upon a precision-weighted integration of afferent signals and prior beliefs. In a previous study, we fit a computational model of perception to behavior on a heartbeat tapping task to test whether aberrant precision-weighting could explain misestimation of cardiac states in psychopathology. We found that, during an interoceptive perturbation designed to amplify afferent signal precision (inspiratory breath-holding), healthy individuals increased the precision-weighting assigned to ascending cardiac signals (relative to resting conditions), while individuals with anxiety, depression, substance use disorders, and/or eating disorders did not. In this pre-registered study, we aimed to replicate and extend our prior findings in a new transdiagnostic patient sample (N = 285) similar to the one in the original study. As expected, patients in this new sample were also unable to adjust beliefs about the precision of cardiac signals - preventing the ability to accurately perceive changes in their cardiac state. Follow-up analyses combining samples from the previous and current study (N = 719) also afforded power to identify group differences between narrower diagnostic categories, and to examine predictive accuracy when logistic regression models were trained on one sample and tested on the other. With this confirmatory evidence in place, future studies should examine the utility of interceptive precision measures in predicting treatment outcomes and test whether these computational mechanisms might represent novel therapeutic targets.

19.
medRxiv ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38947082

ABSTRACT

Elevated anxiety and uncertainty avoidance are known to exacerbate maladaptive choice in individuals with affective disorders. However, the differential roles of state vs. trait anxiety remain unclear, and underlying computational mechanisms have not been thoroughly characterized. In the present study, we investigated how a somatic (interoceptive) state anxiety induction influences learning and decision-making under uncertainty in individuals with clinically significant levels of trait anxiety. A sample of 58 healthy comparisons (HCs) and 61 individuals with affective disorders (iADs; i.e., depression and/or anxiety) completed a previously validated explore-exploit decision task, with and without an added breathing resistance manipulation designed to induce state anxiety. Computational modeling revealed a pattern in which iADs showed greater information-seeking (i.e., directed exploration; Cohen's d=.39, p=.039) in resting conditions, but that this was reduced by the anxiety induction. The affective disorders group also showed slower learning rates across conditions (Cohen's d=.52, p=.003), suggesting more persistent uncertainty. These findings highlight a complex interplay between trait anxiety and state anxiety. Specifically, while elevated trait anxiety is associated with persistent uncertainty, acute somatic anxiety can paradoxically curtail exploratory behaviors, potentially reinforcing maladaptive decision-making patterns in affective disorders.

20.
Psychol Sport Exerc ; 74: 102679, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38797225

ABSTRACT

Physical activity, beneficial for physical and psychological health, may facilitate affective mechanisms of positive emotion and approach-motivation. Greater resting frontal alpha asymmetry (FAA), an index of greater relative left than right frontal cortical activity, is a neural correlate of affective mechanisms possibly associated with active lifestyles. This study sought to amplify limited literature on the relationship between physical (in)activity, FAA, and gender differences. College students (n = 70) self-reported physical activity (Total PA) and sedentary activity (Total Sitting) via the International Physical Activity Questionnaire-Short Form (IPAQ-SF), followed by a resting electroencephalography session to record FAA. A Total PA × gender interaction (ß = 0.462, t = 3.163, p = 0.002) identified a positive relationship between Total PA and FAA in women (ß = 0.434, t = 2.221, p = 0.030) and a negative relationship for men (ß = -0.338, t = -2.300, p = 0.025). Total Sitting was positively linked to FAA (ß = 0.288, t = 2.228, p = 0.029; no gender effect). Results suggest affective mechanisms reflected by FAA (e.g., positive emotion, approach-motivation) are associated with physical activity for women, indicating a possible mechanism of the psychological benefits linked with physically active lifestyles. A positive relationship between sedentary behavior and greater left FAA may also reflect motivated mechanisms of behavior that aid in minimizing energy expenditure, particularly within the context of our highly active sample.


Subject(s)
Exercise , Sedentary Behavior , Humans , Female , Male , Young Adult , Exercise/physiology , Exercise/psychology , Sex Factors , Alpha Rhythm/physiology , Frontal Lobe/physiology , Electroencephalography , Adult , Adolescent , Self Report
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