Crossmodal processing of emotions in alcohol-dependence and Korsakoff syndrome

A biological framework for emotional dysregulation in alcohol misuse: from gut to brain

Alcohol use disorder (AUD) has been associated with impairments in social and emotional cognition that play a crucial role in the development and maintenance of addiction. Repeated alcohol intoxications trigger inflammatory processes and sensitise the immune system. In addition, emerging data point to perturbations in the gut microbiome as a key regulator of the inflammatory cascade in AUD. Inflammation and social cognition are potent modulators of one another. At the same time, accumulating evidence implicates the gut microbiome in shaping emotional and social cognition, suggesting the possibility of a common underlying loop of crucial importance for addiction. Here we propose an integrative microbiome neuro-immuno-affective framework of how emotional dysregulation and alcohol-related microbiome dysbiosis could accelerate the cycle of addiction. We outline the overlapping effects of chronic alcohol use, inflammation and microbiome alterations on the fronto-limbic circuitry as a convergence hub for emotional dysregulation. We discuss the interdependent relationship of social cognition, immunity and the microbiome in relation to alcohol misuse- from binge drinking to addiction. In addition, we emphasise adolescence as a sensitive period for the confluence of alcohol harmful effects and emotional dysregulation in the developing gut-brain axis.

Tackling heterogeneity: Individual variability of emotion decoding deficits in severe alcohol use disorder

BACKGROUND

Severe alcohol use disorder (SAUD) is associated with social cognition deficits. Patients with SAUD are impaired for the recognition of emotional facial expressions, particularly at early stages of abstinence. These deficits damage interpersonal relations and increase relapse risk. However, uncertainties still abound on their variation across emotions and on the heterogeneity of emotional impairments across patients. We addressed these questions by exploring how the deficit varies according to emotions' type/intensity and patients' heterogeneity.

METHODS

Sixty-five recently detoxified patients with SAUD and 65 matched healthy controls performed the Facial Emotion Recognition Test, assessing the ability to identify six emotions (anger, contempt, disgust, fear, happiness, sadness) displayed by morphed faces with various intensities. Accuracy scores and detection thresholds were collected for each emotion. Beyond group comparisons, multiple single-case analyses determined the percentage of patients presenting decoding deficits for each emotion.

RESULTS

When current depression and anxiety symptoms were controlled for, patients did not present a general emotion decoding deficit, but were rather characterized by specific deficits for disgust/contempt in accuracy, and for disgust in detection threshold scores. Single-case analyses showed that only a third of patients presented a clinically significant emotional deficit.

CONCLUSIONS

Patients with SAUD only present emotional decoding deficits for specific interpersonal emotions (disgust/contempt) when subclinical psychopathological states are controlled for, and show no general emotional impairment. This goes against the proposal of a generalized social cognition deficit in this population. This group effect moreover masks a massive heterogeneity across patients, which has implications at experimental and clinical levels.

Selective visual and crossmodal impairment in the discrimination of anger and fear expressions in severe alcohol use disorder

BACKGROUND

Severe alcohol use disorder (SAUD) is associated with impaired discrimination of emotional expressions. This deficit appears increased in crossmodal settings, when simultaneous inputs from different sensory modalities are presented. However, so far, studies exploring emotional crossmodal processing in SAUD relied on static faces and unmatched face/voice pairs, thus offering limited ecological validity. Our aim was therefore to assess emotional processing using a validated and ecological paradigm relying on dynamic audio-visual stimuli, manipulating the amount of emotional information available.

METHOD

Thirty individuals with SAUD and 30 matched healthy controls performed an emotional discrimination task requiring to identify five emotions (anger, disgust, fear, happiness, sadness) expressed as visual, auditory, or auditory-visual segments of varying length. Sensitivity indices (d') were computed to get an unbiased measure of emotional discrimination and entered in a Generalized Linear Mixed Model. Incorrect emotional attributions were also scrutinized through confusion matrices.

RESULTS

Discrimination levels varied across sensory modalities and emotions, and increased with stimuli duration. Crucially, performances also improved from unimodal to crossmodal conditions in both groups, but discrimination for anger crossmodal stimuli and fear crossmodal/visual stimuli remained selectively impaired in SAUD. These deficits were not influenced by stimuli duration, suggesting that they were not modulated by the amount of emotional information available. Moreover, they were not associated with systematic emotional error patterns reflecting specific confusions between emotions.

CONCLUSIONS

These results clarify the nature and extent of crossmodal impairments in SAUD and converge with earlier findings to ascribe a specific role for anger and fear in this pathology.

Emotional processing and social cognition in alcohol use disorder

OBJECTIVE

To review deficits in emotional processing and social cognition potentially contributing to the dysfunctional emotion regulation and difficulties with interpersonal relationships observed in individuals with alcohol use disorder (AUD) and to provide directions for future research.

METHOD

First is presented a review of emotional and social-cognitive impairments in recently detoxified AUD individuals that include alexithymia, difficulties in decoding others' emotions, and reduced theory of mind and empathy skills. Social cognition disorders in AUD pose different issues discussed, such as whether (1) these deficits are consequences of excessive alcohol consumption or premorbid risk factors for addiction, (2) emotional and social impairments impede positive treatment outcome, (3) recovery of social abilities is possible with sustained abstinence, and (4) AUD patients are unaware of their emotional and social dysfunctions. Finally, current knowledge on structural and functional brain correlates of these deficits in AUD are reviewed.

RESULTS

Emotional and social-cognitive functions affected in AUD can potentially compromise efforts to initiate and maintain abstinence by hampering efficacy of clinical treatment. Such dysfunction can obstruct efforts to enable or reinstate higher-order abilities such as emotional self-regulation, motivation to change, success in interpersonal/social interactions, and emotional insight and awareness of social dysfunctions (i.e., accurate metacognition).

CONCLUSIONS

The present review highlights the need to account for emotional processing and social cognition in the evaluation and rehabilitation of alcohol-related neurocognitive disorders and to consider psychotherapeutic treatment involving remediation of emotional and social skills as implemented in psychiatric and neurological disorders. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Cognitive and affective theory of mind in Korsakoff's syndrome

OBJECTIVE

Korsakoff's syndrome (KS) is a chronic neuropsychiatric disorder characterised by severe anterograde amnesia and executive deficits. Theory of Mind (ToM) is the capacity to represent others' mental states such as their knowledge, thoughts, feelings, beliefs, and intentions in order to explain and predict their behaviour. Surprisingly this topic has received hardly any attention in research on KS, although the severity of behavioural problems in KS suggest possible ToM difficulties. The aim of the present study was therefore to assess whether cognitive and affective ToM are impaired in patients with KS.

METHODS

We examined 21 KS patients and 21 age- and gender-matched healthy controls on three standardised tests that assess cognitive and affective ToM, including the subtests of the mini-Social Cognition and Emotional Assessment battery and a specialised version of the Sally-Anne Test.

RESULTS

KS patients showed largely impaired cognitive and affective ToM compared to healthy controls, as reflected in large effect sizes on both cognitive and affective ToM tests. Executive deficits explained problems in emotion recognition, but not other ToM aspects.

CONCLUSION

KS patients have large impairments in both cognitive and affective aspects of social cognition. Their ability to recognise emotions, take the perspective of others, and understand socially awkward situations is vastly compromised. The impairments in ToM functioning are to a large degree functionally discrepant from executive disorders that are commonly present in KS. This study therefore highlights the importance to properly index ToM functioning in neuropsychological assessments for individuals with a possible KS diagnosis.

Behavioral and Cerebral Impairments Associated with Binge Drinking in Youth: A Critical Review

Binge drinking is a widespread alcohol consumption pattern in youth that is linked to important behavioral and cerebral impairments, in both the short and the long term. From a critical review of the current literature on this topic, we conclude that binge drinkers display executive impairments, cerebral modifications, and problems with emotion-related processes. Five key empirical and theoretical topics are discussed to pave the way for future research in the field: (1) the specificity of the brain modifications observed in binge drinkers that may index a compensatory mechanism or result from multiple withdrawals; (2) the nature of the relationship between binge drinking and impairments, suggesting reciprocal influences between excessive alcohol consumption and executive deficits; (3) the possible recovery of brain and cognitive functioning after the cessation of binge drinking; (4) the validity of the continuum hypothesis, suggesting links between binge drinking and severe alcohol use disorders; and (5) the existing strategies to reduce binge drinking habits or rehabilitate the associated cognitive deficits. Future perspectives are described in relation to the questions raised to identify the crucial variables to be addressed in research and clinical practice.

Disrupted Brain Network Efficiency and Decreased Functional Connectivity in Multi-sensory Modality Regions in Male Patients With Alcohol Use Disorder

Background: Recent studies have reported altered efficiency in selective brain regions and functional networks in patients with alcohol use disorder (AUD). Inefficient processing can reflect or arise from the disorganization of information being conveyed from place to place. However, it remains unknown whether the efficiency and functional connectivity are altered in large-scale topological organization of patients with AUD.

Methods: Resting-state functional magnetic resonance imaging (rsfMRI) data were experimentally collected from 21 right-handed males with AUD and 21 right-handed, age-, gender- and education-matched healthy controls (HCs). Graph theory was used to investigate inter-group differences in the topological parameters (global and nodal) of networks and inter-regional functional connectivity. Correlations between group differences in network properties and clinical variables were also investigated in the AUD group.

Results: The brain networks of the AUD group showed decreased global efficiency when compared with the HC group. Besides, increased nodal efficiency was found in the left orbitofrontal cortex (OFC), while reduced nodal efficiency was observed in the right OFC, right fusiform gyrus (FFG), right superior temporal gyrus, right inferior occipital gyrus (IOG), and left insula. Moreover, hypo-connectivity was detected between the right dorsolateral prefrontal cortex (DLPFC) and right superior occipital gyrus (SOG) in the AUD group when compared with the HC group. The nodal efficiency of the left OFC was associated with cognitive performance in the AUD group.

Conclusions: AUD patients exhibited alterations in brain network efficiency and functional connectivity, particularly in regions linked to multi-sensory modalities. These disrupted topological properties may help to obtain a more comprehensive understanding of large-scale brain network activity. Furthermore, these data provide a potential neural mechanism of impaired cognition in individuals with AUD.

Impaired affective prosody decoding in severe alcohol use disorder and Korsakoff syndrome

Recognizing others' emotions is a fundamental social skill, widely impaired in psychiatric populations. These emotional dysfunctions are involved in the development and maintenance of alcohol-related disorders, but their differential intensity across emotions and their modifications during disease evolution remain underexplored. Affective prosody decoding was assessed through a vocalization task using six emotions, among 17 patients with severe alcohol use disorder, 16 Korsakoff syndrome patients (diagnosed following DSM-V criteria) and 19 controls. Significant disturbances in emotional decoding, particularly for negative emotions, were found in alcohol-related disorders. These impairments, identical for both experimental groups, constitute a core deficit in excessive alcohol use.

Impact of intranasal oxytocin on interoceptive accuracy in alcohol users: an attentional mechanism?

Interoception, i.e. the perception and appraisal of internal bodily signals, is related to the phenomenon of craving, and is reportedly disrupted in alcohol use disorders. The hormone oxytocin influences afferent transmission of bodily signals and, through its potential modulation of craving, is proposed as a possible treatment for alcohol use disorders. However, oxytocin's impact on interoception in alcohol users remains unknown. Healthy alcohol users (n = 32) attended two laboratory sessions to perform tests of interoceptive ability (heartbeat tracking: attending to internal signals and, heartbeat discrimination: integrating internal and external signals) after intranasal administration of oxytocin or placebo. Effects of interoceptive accuracy, oxytocin administration and alcohol intake, were tested using mixed-effects models. On the tracking task, oxytocin reduced interoceptive accuracy, but did not interact with alcohol consumption. On the discrimination task, we found an interaction between oxytocin administration and alcohol intake: Oxytocin, compared with placebo, increased interoceptive accuracy in heavy drinkers, but not in light social drinkers. Our study does not suggest a pure interoceptive impairment in alcohol users but instead potentially highlights reduced flexibility of internal and external attentional resource allocation. Importantly, this impairment seems to be mitigated by oxytocin. This attentional hypothesis needs to be explicitly tested in future research.