The Translational Value of Psychophysiology Methods and Mechanisms: Multilevel, Dynamic, Personalized

Applying dynamic systems theory and complexity theory methods in psychotherapy research: A systematic literature review

OBJECTIVE

Dynamic systems theory and complexity theory (DST/CT) is a framework explaining how complex systems change and adapt over time. In psychotherapy, DST/CT can be used to understand how a person's mental and emotional state changes during therapy incorporating higher levels of complexity. This study aimed to systematically review the variability of DST/CT methods applied in psychotherapy research.

METHODS

A primary studies search was conducted in the EBSCO and Web of Knowledge databases, extracting information about the analyzed DST/CT phenomena, employed mathematical methods to investigate these phenomena, descriptions of specified dynamic models, psychotherapy phenomena, and other information regarding studies with empirical data (e.g., measurement granularity).

RESULTS

After screening 38,216 abstracts and 4,194 full texts, N = 41 studies published from 1990 to 2021 were identified. The employed methods typically included measures of dynamic complexity or chaoticity. Computational and simulation studies most often employed first-order ordinary differential equations and typically focused on describing the time evolution of client-therapist dyadic influences. Eligible studies with empirical data were usually based on case studies and focused on data with high time intensity of within-session dynamics.

CONCLUSION

This review provides a descriptive synthesis of the current state of the proliferation of DST/CT methods in the psychotherapy research field.

Effects of arousal modulation via resonance breathing on craving and affect in women with substance use disorder

BACKGROUND

Craving for alcohol and other drugs is a complex in-the-moment experience that involves within-person changes in physiological arousal and affect. We evaluated the utility of a just-in-time, self-administered resonance breathing smartphone application (app) to reduce craving and improve affect in women during outpatient treatment for substance use disorders (SUD).

METHODS

Women (N = 57) receiving outpatient addiction treatment were randomized to practice either cardiovascular resonance breathing (0.1 Hz/6 breaths per minute) or a sham (∼0.23 Hz/14 breaths per minute) in the face of urges over an 8-week intervention. Craving (Penn Alcohol Craving Scale) and affect (Positive and Negative Affect Scale) were collected weekly throughout the intervention. App data were uploaded weekly to assess frequency of use. Generalized Estimated Equations modeled craving and affect as a function of group randomization and app use frequency across the 8-week intervention.

FINDINGS

Higher levels of craving were associated with more frequent app use. The group X app use interaction was significant for craving. Frequent app use during the intervention phase was associated with lower craving levels in the resonance breathing group relative to the sham group over the 8-week intervention. There was no effect of app use frequency on affect measures.

CONCLUSIONS

Women assigned to practice sham breathing who used the intervention frequently experienced elevations in craving that are commonly reported during outpatient SUD treatment. Women assigned to resonance breathing who used the intervention frequently did not experience such increases. Resonance breathing may be protective against triggers in outpatient treatment. Physiological mechanisms are discussed.

Closing the brain-heart loop: Towards more holistic models of addiction and addiction recovery

Much research seeks to articulate the brain structures and pathways implicated in addiction and addiction recovery. Prominent neurobiological models emphasize the interplay between cortical and limbic brain regions as a main driver of addictive processes, but largely do not take into consideration sensory and visceral information streams that link context and state to the brain and behavior. Yet these brain-body information streams would seem to be necessary elements of a comprehensive model of addiction. As a starting point, we describe the overlap between one current model of addiction circuitry and the neural network that not only regulates cardiovascular system activity but also receives feedback from peripheral cardiovascular processes through the baroreflex loop. We highlight the need for neurobiological, molecular, and behavioral studies of neural and peripheral cardiovascular signal integration during the experience of internal states and environmental contexts that drive alcohol and other drug use behaviors. We end with a call for systematic, mechanistic research on the promising, yet largely unexamined benefits to addiction treatment of neuroscience-informed, adjunctive interventions that target the malleability of the cardiovascular system to alter brain processes.

Pilot examination of stress, heart rate variability, and alcohol craving and use among female veterans

Rates of alcohol use disorder (AUD) are increasing among civilian and veteran populations of women in the United States, and stress pathophysiology (i.e., abnormal acute and long-term change in physiological responses to stress) is central to the maintenance of alcohol misuse within this population. Heart rate variability (HRV) is one measure of stress regulation that may help to explain the association of stress with alcohol misuse among women. In the current analysis of pilot data, 20 women veterans attended an in-person laboratory session and completed 35 daily assessments of their alcohol use and craving. During the lab session, the effects of a stress induction procedure on self-reported alcohol craving and HRV were assessed. HRV was continuously measured and indexed in the time domain, using the root mean square of successive differences between normal heartbeats (RMSSD). Alcohol craving and use during the longitudinal 35-day study period were measured via self-report questionnaires sent to participants' phones. Results indicated that resting HRV in the lab was positively associated with odds of daily craving. Moreover, HRV during the stressor, as measured in lab, was positively associated with (1) overall alcohol craving in the lab (i.e., with resting and post-stress craving), and (2) number of daily drinks during the 35-day study period. This pilot study suggests the potential role of HRV in response to stressors in predicting alcohol craving and use among female veterans. It provides pilot data for research on stress-reactive HRV as a biomarker for alcohol misuse among women, and discusses directions for future research.

Getting to the Heart of Low Sensitivity to Alcohol: Context Moderates Low Cardiovascular Response to Alcohol in Persons With a Family History of Alcohol Use Disorder

Background

Low sensitivity to alcohol in persons with a family history of alcoholism (FH+), compared to those without (FH−), contributes to risk for alcohol use disorder (AUD). However, sensitivity of FH+ cardiovascular response to alcohol is not well understood. This gap is significant because cardiovascular processes contribute to emotional regulation and stress response problems theorized to be central to the development and persistence of AUD. This study compared changes in heart rate (HR) and HR variability (HRV) between FH groups after consuming alcohol and control beverages and examined how these changes were moderated by emotional and alcohol‐related contexts.

Methods

Young adults (N = 165) with FH+ (n = 110) or FH− (n = 55) each completed 2 sessions, separated by 1 week. They received one of 3 different beverages (alcohol, placebo, and told‐no‐alcohol) in each session. Electrocardiogram data were recorded during pre–beverage consumption and post–beverage consumption baselines, and then during 4 picture cue tasks (neutral, positive, negative, and alcohol‐related). Generalized estimating equations were used to examine differences in cardiovascular reactivity (changes in HR and HRV power at ~ 0.1 Hz) across FH groups, beverage conditions, and picture cue tasks.

Results

A significant beverage condition × cue task × FH interaction effect on HRV was observed. The FH+ group, compared to the FH− group, showed (a) significantly less HRV suppression in specific cue contexts following alcohol, (b) a mixed pattern of more and less HRV suppression across cue contexts following placebo, and (c) a similar HRV reactivity pattern in the told‐no‐alcohol condition across cue tasks. For HR, there were no significant effects involving FH.

Conclusions

Diminished cardiovascular sensitivity to oral alcohol in FH+ persons varied within a given drinking episode depending on emotional and alcohol‐related features of the context, suggesting that environmental characteristics play a role in the expression of low sensitivity to alcohol among FH+ individuals.

Improvement in women's cardiovascular functioning during cognitive-behavioral therapy for alcohol use disorder

The cardiovascular system is disrupted by chronic excessive alcohol use and often impaired in individuals with an alcohol use disorder (AUD). Less is known about cardiovascular recovery when an individual receives treatment for AUD. This observational study aimed to extend the growing body of evidence for cardiovascular biomarkers and intervention targets in the treatment of AUD. We examined cardiovascular function in 92 women before and after 12 weeks of cognitive-behavioral therapy (CBT) for AUD. Participants were recruited exclusively from a randomized clinical trial comparing group versus individual CBT treatment strategies (parent study); no control group of untreated, but treatment-seeking women was available. Demographic and drinking data were obtained from the parent study. Cardiovascular data were collected as part of this separate study, prior to and following the clinical trial. Mixed-model analyses revealed multiple within-person cardiovascular changes indicative of improving health from pre- to posttreatment, including reduced heart rate and vessel stiffness as well as increased heart rate variability and baroreflex sensitivity. These significant improvements remained when extent of drinking during treatment was included in the models, suggesting that active ingredients of AUD treatment may serve to benefit physical health over and above drinking reductions. Future studies should assess the time course of cardiovascular recovery during addiction treatment and the mechanisms by which evidence-based AUD treatments may benefit physical as well as mental health. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Substance craving changes in university students receiving heart rate variability biofeedback: A longitudinal multilevel modeling approach

BACKGROUND

Previously published findings from a study of university students living in substance use disorder (SUD) recovery housing showed an eight-session heart rate variability biofeedback (HRVB) intervention significantly reduced craving. That study, however, uncovered pronounced inter-participant variability in craving change patterns through the course of HRVB that warranted further exploration. The purpose of the current investigation was to examine how within- and between-person factors may have differentially influenced craving changes.

METHODS

A longitudinal multilevel modeling approach was used with time at level-1 nested within persons at level-2. Multilevel models of change were estimated to model craving trajectories and predictor relationships over time as a function of age, sex, length of abstinence, daily HRVB practice, anxiety, depression, and stress.

RESULTS

A quadratic pattern of craving reductions was found, indicating that craving reductions accelerated over time for some participants. Daily HRVB practice of >12 min and older age significantly enhanced craving reductions over time. Increases in depressive symptoms attenuated the effects of HRVB on craving. The other predictors were not significantly associated with craving in this study. The true R² for the final model indicated that 20.5% of the variance in craving was explained by older age, daily HRVB >12 min, and within-person changes in depression.

CONCLUSIONS

HRVB shows promise as an accessible, scalable, and cost-effective complementary anti-craving intervention. Healthcare providers may help persons recovering from SUD to better manage substance craving by the routine and strategic use of HRVB practice.

Theoretical implications and clinical support for heart rate variability biofeedback for substance use disorders

Heart rate variability (HRV) biofeedback is an accessible, cost-effective intervention that has demonstrated clinical value for numerous physical and mental health conditions; however, research on HRV biofeedback in substance use disorders (SUD) is in its nascence. We argue that HRV biofeedback may be particularly beneficial as an adjunct treatment for SUD by targeting bodily systems that are known to be disrupted by chronic substance use and are not historically the focus of psychosocial or pharmacological SUD treatment approaches. In addition to advocating for HRV biofeedback applications in SUD, we identify several gaps within the existing experimental literature, and propose new studies that could accelerate understanding of how and for whom HRV biofeedback is most likely to promote positive behavior change.

Resonance-Paced Breathing Alters Neural Response to Visual Cues: Proof-of-Concept for a Neuroscience-Informed Adjunct to Addiction Treatments

Conscious attempts to regulate alcohol and drug use are often undermined by automatic attention and arousal processes that are activated in the context of salient cues. Response to these cues involves body and brain signals that are linked via dynamic feedback loops, yet no studies have targeted the cardiovascular system as a potential conduit to alter automatic neural processes that maintain cue salience. This proof-of-concept study examined within-person changes in neural response to parallel but unique sets of visual alcohol-related cues at two points in time: prior to versus following a brief behavioral intervention. The active intervention was resonance breathing, a rhythmical breathing task paced at 0.1 Hz (6 breaths per minute) that helps normalize neurocardiac feedback. The control intervention was a low-demand cognitive task. Functional magnetic resonance imaging (fMRI) was used to assess changes in brain response to the cues presented before (A1) and after (A2) the intervention in 41 emerging adult men and women with varying drinking behaviors. The resonance breathing group exhibited significantly less activation to A2 cues compared with A1 cues in left inferior and superior lateral occipital cortices, right inferior lateral occipital cortex, bilateral occipital pole, and temporal occipital fusiform cortices. This group also showed significantly greater activation to A2 cues compared with A1 cues in medial prefrontal, anterior and posterior cingulate, and precuneus cortices, paracingulate, and lingual gyri. The control group showed no significant changes. Thus, following resonance breathing, activation in brain regions involved in visual processing of cues was reduced, while activation in brain areas implicated in behavioral control, internally directed cognition, and brain-body integration was increased. These findings provide preliminary evidence that manipulation of the cardiovascular system with resonance breathing alters neural activation in a manner theoretically consistent with a dampening of automatic sensory input and strengthening of higher-level cognitive processing.

Current Evidence on Heart Rate Variability Biofeedback as a Complementary Anticraving Intervention

BACKGROUND

The limited success of conventional anticraving interventions encourages research into new treatment strategies. Heart rate variability biofeedback (HRVB), which is based on slowed breathing, was shown to improve symptom severity in various disorders. HRVB, and certain rates of controlled breathing (CB), may offer therapeutic potential as a complementary drug-free treatment option to help control substance craving.

METHODS

This review evaluated current evidence on the effectiveness of HRVB and CB training as a complementary anticraving intervention, based on guidelines from the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Studies that assessed a cardiorespiratory feedback or CB intervention with substance craving as an outcome were selected. Effect sizes were calculated for each study. The Scale for Assessing Scientific Quality of Investigations in Complementary and Alternative Medicine was used to evaluate the quality of each study reviewed.

RESULTS

A total of eight articles remained for final review, including controlled studies with or without randomization, as well as noncontrolled trials. Most studies showed positive results with a variety of methodological quality levels and effect size. Current HRVB studies rated moderately on methodological rigor and showed inconsistent magnitudes of calculated effect size (0.074-0.727) across populations. The largest effect size was found in a nonclinical college population of high food cravers utilizing the most intensive HRVB training time of 240 min.

CONCLUSIONS

Despite the limitations of this review, there is beginning evidence that HRVB and CB training can be of significant therapeutic potential. Larger clinical trials are needed with methodological improvements such as longer treatment duration, adequate control conditions, measures of adherence and compliance, longitudinal examination of craving changes, and more comprehensive methods of craving measurement.