The past two decades have seen significant advances in our understanding of the neuroscience of addiction and its implications for practice [reviewed in ]. However, despite such insights, there is a substantial lag in translating these findings into everyday practice, with few clinicians incorporating neuroscience-informed interventions in their routine practice . We recently launched the Neuroscience Interest Group within the International Society of Addiction Medicine to promote initiatives to bridge this gap between knowledge and practice. This article introduces the ISAM-NIG key priorities and strategies to achieve implementation of addiction neuroscience knowledge and tools in the assessment and treatment of substance use disorders . We cover four broad areas:cognitive assessment,neuroimaging,cognitive training and remediation, and neuromodulation. Cognitive assessment and neuroimaging provide multilevel biomarkers to be targeted with cognitive and neuromodulation interventions. Cognitive training/ remediation and neuromodulation provide neuroscience informed interventions to ameliorate neural, cognitive, and related behavioral alterations and potentially improve clinical outcomes in people with SUD. In the following sections, we review the current knowledge and challenges in each of these areas and provide ISAM-NIG recommendations to link knowledge and practice. Our goal is for researchers and clinicians to work collaboratively to address these challenges and recommendations. Cutting across the four areas,hydroponic vertical farming we focus on cognitive and neural systems that predict meaningful clinical outcomes for people with SUD and opportunities for harmonized assessment and intervention protocols.
Neuropsychological studies consistently demonstrate that many people with SUD exhibit mild to moderately severe cognitive deficits in processing speed, selective, and sustained attention, episodic memory, executive functions , decision-making and social cognition . Furthermore, neurobiologically informed theories and expert consensus have identified additional cognitive changes not typically assessed by traditional neuropsychological measures, namely, negative affectivity and reward-related processes. Cognitive deficits in SUD have moderate longevity, and although there is abstinence-related recovery , these deficits may significantly complicate treatment efforts during the first 3 to 6 months after discontinuation of drug use. Thus, one of the most critical implications of cognitive deficits for SUD is their potential negative impact on treatment retention and adherence, in addition to clinical outcomes such as craving, relapse, and quality of life. A systematic review of prospective cognitive studies measuring treatment retention and relapse across different SUD suggested that measures of processing speed and accuracy during attention and reasoning tasks were the only consistent predictors of treatment retention, whereas tests of decision-making were the only consistent predictors of relapse . A later review that focused on substance-specific cognitive predictors of relapse found that long-term episodic memory and higher-order EF predicted alcohol relapse, whereas attention and higher-order EF predicted stimulant relapse, while only higher-order EF predicted opioid relapse . Working memory and response inhibition have also been associated with increased risk of relapse among cannabis and stimulant users . Additionally, variation in response inhibition has been shown to predict poorer recovery of quality of life during SUD treatment . Therefore, consistent evidence suggests that processing speed, attention, and reasoning are critical targets for current SUD treatments, whereas higher-order EF and decision-making are critical for maintaining abstinence. Response inhibition deficits seem to be specifically associated with relapse prediction in cannabis and stimulant users and also predict quality of life.The workforce in the SUD specialist treatment sector is diverse, encompassing medical specialists, allied health professionals, generalist health workers, and peer and volunteer workers .
For instance, in the Australian context, multiple workforce surveys over the past decade suggest that around half the workforce have attained a tertiary level Bachelor degree or greater . Similarly, US and European data has shown that education qualifications in the SUD workforce are lower than in other health services . Because the administration and interpretation of many cognitive tests are restricted to individuals with specialist qualifications, this limits their adoption in the sector. In addition, when screening does occur in SUD treatment settings, its primary function is to identify individuals requiring referral to specialist service providers for more comprehensive assessment and intervention, rather than to inform individual treatment plans. Two fields in particular have driven progress in cognitive assessment practice for generalist workers: dementia, with an increasing emphasis on screening in primary care , and schizophrenia, where cognitive impairment is an established predictor of functional outcome necessitating the development of a standardized assessment battery specifically for this disorder. In the selection of domain-specific tests for the Measurement and Treatment Research to Improve Cognition in Schizophrenia standard battery, a particular emphasis was placed on test practicality and tolerability, as well as psychometric quality. Pragmatic issues of administration time, scoring time and complexity, and test difficulty and unpleasantness for the client should be considered .The dementia screening literature has also emphasized these pragmatic issues, leading to a greater awareness and access to general cognitive screening tools.To date, the majority of the published literature on routine cognitive screening in SUD contexts has focused on three tests commonly used in dementia screening : the Mini-Mental State Examination, Addenbrooke’s Cognitive Examination, and the Montreal Cognitive Assessment. Due to their development for application in dementia contexts, these screening tools placed a heavy emphasis on memory, attention, language and visuo spatial functioning . Multiple studies have demonstrated superior sensitivity of the MoCA and the ACE scales compared to the MMSE . It is possible that this arises from the MoCA and ACE including at least some items assessing EF which are absent in the MMSE.
Indeed, this may demonstrate an important limitation of adopting existing screening tools designed for dementia in the context of SUD treatment. It can be argued that cognitive screening is most beneficial in SUD contexts when focused on SUD-relevant domains, rather than the identification of general cognitive deficits. Therefore, current neuroscience based frameworks emphasise the importance of assessing EF, incentive salience, and decision-making in SUD . As such, there is much to be gained by applying a process similar to the MATRICS effortin the SUD field to identify a ‘gold-standard’ set of practical and sensitive cognitive tests that can be routinely used in clinical practice.The most commonly used cognitive assessment approach in SUD research has been the “flexible test battery”. This approach combines different types of tests to measure selected cognitive domains . Attention, memory, EF, and decision-making are the most commonly assessed domains, although there is a considerable discrepancy in the tests selected to assess these constructs . Even within specific tests, different studies have used several different versions; for example, at least four different versions of the Stroop test have been employed in the SUD literature . Another commonly used approach is the “fixed test battery”, which involves a comprehensive suite of tests that have been jointly standardized and provide a general profile of cognitive impairment. The Cambridge Automated Neuropsychological Test Battery, the Repeatable Battery for the Assessment of Neuropsychological Status,vertical agriculture the Neuropsychological Assessment Battery– Screening Module and the MicroCog™are examples of fixed test batteries utilized in SUD research , although these too have limited assessment of EF. Another limitation of these assessment modules is the lack of construct validity, as they were not originally designed to measure SUD-related cognitive deficits. As a result, they overemphasize assessment of cognitive domains that are relatively irrelevant in the context of SUD and neglect other domains that are pivotal . A common limitation of flexible and fixed batteries is their reliance on face-to-face testing, normally involving a researcher or clinician, and their duration, which is typically around 60-90 min. To address this gap, a number of semi-automated tests of cognitive performance have been developed, including the Automated Neuropsychological Assessment Metrics , ImmediatePost-concussion Assessment and Cognitive Testing battery , and CogState brief battery, have been used more widely, although validation studies to date suggest they may not yet have sufficient psychometric evidence to support clinical use . Research specifically in addictions has begun to develop and validate cognitive tests that can be delivered in client/participants’ homes or via smartphone devices. Evaluations of the reliability, validity, and feasibility of mobile cognitive assessment in individuals with SUD have been scarce, but promising . Cognitive assessment via smartphone applications and web based computing is a rapidly developing field, following many of the procedures and traditions of Ecological Momentary Assessment. The flexibility and rapidity of assessment offered by mobile applications makes it particularly suited to questions assessing change in cognitive performance over various time scales . For example, cognitive performance can be assessed in event-based , time-based and randomly prompted procedures that were not previously feasible, and or valid, in laboratory testing. While the benefits of mobile testing to longitudinal research, particularly large-scale clinical trials, appear obvious , the rapidity and frequency of deployment also provide opportunities to test questions of much shorter delays between drug use behavior and cognition.
For example, recent studies have examined if daily within-individual variability in cognitive performance, principally response inhibition, was associated with variable likelihood for binge alcohol consumption . Similarly, influencing the immediate dynamic relationship between cognition and drug use has also been used for intervention purposes. Web and smartphone platforms have been used to administer cognitive-task based interventions, such as cognitive bias modification training , where cognitive performance is routinely measured as a central element of interventions that span several weeks. The outcomes of these trials show that mobile cognitive-task based interventions are feasible but not efficacious as in a stand-alone context . However, the combination of cognitive bias modification and normative feedback significantly reduces weekly alcohol consumption in excessive drinkers .A substantial proportion of people with SUD have cognitive deficits. Alcohol, stimulants and opioid users have overlapping deficits in EF and decision-making. Alcohol users have additional deficits in learning and memory and psychomotor speed. Heavy cannabis users have specific deficits in episodic memory and attention. Cognitive assessments of speed/attention, EF and decision-making are meaningfully associated with addiction treatment outcomes such as treatment retention, relapse and quality of life . In addition, there is growing evidence that motivational and affective domains are also implicated in SUD pathophysiology and clinical symptoms . For example, both reward expectancy and valuation and negative affect have been proposed to explain SUD chronicity . However, to date, there have been no studies linking these “novel domains” with clinical outcomes. Thus, it is important to explore the predictive validity of non-traditional cognitive-motivational and cognitive-affective domains in relation to treatment response. While flexible and fixed test batteries are the most common assessment approaches, data comparability is alarmingly low and future studies should aim to apply harmonized methods . Remote monitoring and mobile cognitive assessment remain in a nascent stage for SUD research and clinical care. It is too early to make accurate cost-benefit assessments of different mobile methodologies. Yet, their potential to provide more cost-effective assessment with larger and more representative samples and in greater proximity to drug use behavior justifies continued investment into their development.One of the main challenges for the cognitive assessment of people with SUD is the disparity of tests applied across sites and studies, and the lack of a common ontology and harmonized assessment approach . Furthermore, harmonization efforts must accommodate clinicians’ needs, including brevity, simplicity, and automated scoring and interpretation . Mobile cognitive testing is a highly promising approach, although its reliability and validity are influenced by a number of key factors. Test compliance, or lack thereof, seems to be problematic. A recent meta-analysis suggested that the compliance rate for EMA with SUD samples was below the recommended rate of 80% . Designs including participant-initiated event-based assessments were associated with test compliance issues, whereas duration and frequency of assessment were not. While the latter finding suggests that extensive cognitive assessment may be feasible with mobile methods, caution is advised with regard to the scope and depth of the data that can be obtained with these brief assessments and the validity of data sets collected . Remote methods for assessing confounds such as task distraction, malingering, and “cheating” are not well established or validated. As the capability of smartphones, for example, increases, so will the potential to minimize or control for such variables. Face-recognition and fingerprint technology has been proposed for ensuring identity compliance, although this presents ethical issues regarding confidential and de-identified data collection from samples that engage in illicit drug use .