Neurobiological and psychophysiological correlates of emotional dysregulation in ADHD patients

Targeting working memory to modify emotional reactivity in adult attention deficit hyperactivity disorder: a functional magnetic resonance imaging study

Understanding the neural mechanisms of emotional reactivity in Attention-Deficit/Hyperactivity Disorder (ADHD) may help develop more effective treatments that target emotion dysregulation. In adult ADHD, emotion regulation problems cover a range of dimensions, including emotional reactivity (ER). One important process that could underlie an impaired ER in ADHD might be impaired working memory (WM) processing. We recently demonstrated that taxing WM prior to the exposure of emotionally salient stimuli reduced physiological and subjective reactivity to such cues in heavy drinkers, suggesting lasting effects of WM activation on ER. Here, we investigated neural mechanisms that could underlie the interaction between WM and ER in adult ADHD participants. We included 30 male ADHD participants and 30 matched controls. Participants performed a novel functional magnetic resonance imaging paradigm in which active WM-blocks were alternated with passive blocks of negative and neutral images. We demonstrated group-independent significant main effects of negative emotional images on amygdala activation, and WM-load on paracingulate gyrus and dorsolateral prefrontal cortex activation. Contrary to earlier reports in adolescent ADHD, no impairments were found in neural correlates of WM or ER. Moreover, taxing WM did not alter the neural correlates of ER in either ADHD or control participants. While we did find effects on the amygdala, paCG, and dlPFC activation, we did not find interactions between WM and ER, possibly due to the relatively unimpaired ADHD population and a well-matched control group. Whether targeting WM might be effective in participants with ADHD with severe ER impairments remains to be investigated.

The Efficacy of Parent-Child Interaction Therapy (PCIT) in Children with Attention Problems, Hyperactivity, and Impulsivity in Dubai

Disruptive behaviors can be associated with significant functional impairment. Early intervention for young children is essential to prevent long-term consequences. Parent-Child Interaction Therapy (PCIT) is a psychotherapeutic intervention, which has shown to be effective for children with externalizing symptoms. We present the treatment course of PCIT for two kindergarten children. The first has Attention-Deficit/Hyperactivity Disorder (ADHD), and the second has frontal lobe epilepsy. Both presented with attention problems, hyperactivity, and impulsivity associated with significant impairment in multiple settings. Two certified PCIT therapists provided 17 sessions to the parents of the first patient and 25 sessions to the parents of the second patient. Most of the sessions were in-person; however, some were “virtual” due to the circumstances associated with the COVID-19 pandemic. Parents of both patients achieved the “mastery” criteria. In both cases, PCIT contributed to improving the disruptive behaviors. PCIT may serve as an effective therapeutic option for young children with externalizing symptoms in Dubai.

The amygdala in adolescents with attention-deficit/hyperactivity disorder: Structural and functional correlates of delay aversion

OBJECTIVES

Recent magnetic resonance imaging (MRI) studies implicate structural alterations of amygdala, a brain region responsible for processing and experiencing negative emotions, in adolescents with attention-deficit/hyperactivity disorder (ADHD). Here we examined ADHD-related structural correlates of amygdala functional activity elicited during a functional MRI task designed to test behavioural and brain responses to the imposition of delay - an event known to both elicit amygdala hyperactivation and aversity in ADHD.

METHODS

Structural MRI scans from 28 right-handed male adolescents with combined type ADHD and 32 age-matched controls were analysed. Regional grey matter volumes of ADHD and control participants (P[FWE] < 0.05) were correlated with delay aversion self-ratings and neural activity in response to delay-related cues on the Escape Delay Incentive fMRI task.

RESULTS

ADHD was associated with significantly reduced volumes in bilateral amygdala, parahippocampal and temporal gyrus (P[FWE] < 0.05), greater basolateral amygdala activation to delay-related cues (P[FWE] < 0.05) and higher delay aversion self-ratings. Amygdala volume reductions were significantly correlated with, and statistically mediated the pathway from ADHD to, delay-cue-related amygdala hyperactivity (P < 0.01) and self-reported delay aversion (P < 0.01).

CONCLUSIONS

We provide the first evidence of the functional significance of reduced amygdala volumes in adolescents with ADHD by highlighting its relation to delay-induced brain activity that is linked to delay aversion.

SDQ Dysregulation Profile and Its Relation to the Severity of Psychopathology and Psychosocial Functioning in a Sample of Children and Adolescents With ADHD

Objective: A substantial number of children and adolescents with ADHD show severe affective and behavioral dysregulation. A dysregulation profile (DP) distinguishes those participants at a higher risk of comorbidity, dysfunction, and a poorer response to treatment. It was identified as high scoring in certain subscales of the Strengths and Difficulties Questionnaire (SDQ-DP). We developed a cross-sectional study to assess the clinical utility of the SDQ-DP in ADHD. Method: Two hundred fifty clinic-referred children and adolescents with ADHD were assessed. Univariate and linear regression analyses were performed to compare those participants with high levels of SDQ-DP with those with low levels, as well as to examine the association between the SDQ-DP and clinical variables. Results: In all, 28% of ADHD participants had high levels of SDQ-DP. These participants showed higher functional impairment and clinical severity. Conclusion: The use of the SDQ-DP will enable identification of those ADHD patients at greater risk.

Recognition of emotional facial expressions in adolescents with attention deficit/hyperactivity disorder

INTRODUCTION

Attention Deficit/Hyperactivity Disorder (ADHD) is associated with impaired social competencies, due in part to an inability to determine emotional states through facial expressions. Social interactions are a critical component of adolescence, which raises the question of how do adolescents with ADHD cope with this impairment. Yet, previous reviews do not distinguish between children and adolescents. This review focuses on the ability of adolescents (defined by the World Health Organization as 10-19 years old) with ADHD to recognize emotional facial expressions, when compared to their typically-developing peers.

METHODS

Comprehensive database search and analysis yielded 9 relevant studies published between 2008 and 2018.

RESULTS

The studies reviewed here examined recognition of emotional facial expressions in adolescents with ADHD. Behavioral measures (reaction time, reaction time variance and recognition accuracy) show no statistically significant differences between adolescents with ADHD and their typically-developing peers. However, neural responses as recorded using functional Magnetic Resonance Imaging (fMRI) or Event Related Potentials (ERP) find differences in brain activity and the temporal evolution of the reaction between the two groups.

CONCLUSIONS

Studies of children and of adults with ADHD find deficiencies in the recognition of emotional facial expressions. However, this review shows that adolescents with ADHD perform comparably to their peers on accuracy and rate, although their neural processing is different. This suggests that the methodologies employed by the ADHD and typically-developing adolescents to asses facial expressions are different. Further study is needed to determine what these may be.

Patients with mutations of the Thyroid hormone beta-receptor show an ADHD-like phenotype for performance monitoring: an electrophysiological study

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Mutations in the thyroid hormone receptor beta (THRB) lead to relative hyperthyroidism in the brain.

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Electrophysiological biomarkers of performance monitoring (ERN and Pe components) show a pattern similar to ADHD in carriers of THRB mutations.

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The phenotype of THRB mutation carriers is indistinguishable from ADHD with regard to performance monitoring.

Resistance to thyroid hormone beta (RTHβ) is a syndrome of reduced responsiveness of peripheral tissue to thyroid hormone, caused by mutations in the thyroid hormone receptor beta (THRB). Its cognitive phenotype has been reported to be similar to attention deficit hyperactivity disorder (ADHD). This study used electrophysiological biomarkers of performance monitoring in RTHβ to contribute further evidence on its phenotypical similarity to ADHD. Twenty-one participants with RTHβ aged 18–67 years and 21 matched healthy controls performed a modified flanker task during EEG recording. The RTHβ and control groups were compared on behavioural measures and components of event related potentials (ERPs), i.e. the error related negativity (ERN), the error positivity (Pe) and P3 component. There were no significant group differences with regard to behaviour. RTHβ subjects displayed significantly reduced ERN and Pe amplitudes compared to the controls in the response-locked ERPs. In addition, we observed reduced P3 amplitudes in both congruent and incongruent trials, as well as prolonged P3 latencies in RTHβ subjects in the stimulus-locked ERPs. Our findings reveal alterations in error detection and performance monitoring of RTHβ patients, likely indicating reduced error awareness. The electrophysiological phenotype of RTHß subjects with regard to action monitoring is indistinguishable from ADHD.

CK1δ over-expressing mice display ADHD-like behaviors, frontostriatal neuronal abnormalities and altered expressions of ADHD-candidate genes

The cognitive mechanisms underlying attention-deficit hyperactivity disorder (ADHD), a highly heritable disorder with an array of candidate genes and unclear genetic architecture, remain poorly understood. We previously demonstrated that mice overexpressing CK1δ (CK1δ OE) in the forebrain show hyperactivity and ADHD-like pharmacological responses to D-amphetamine. Here, we demonstrate that CK1δ OE mice exhibit impaired visual attention and a lack of D-amphetamine-induced place preference, indicating a disruption of the dopamine-dependent reward pathway. We also demonstrate the presence of abnormalities in the frontostriatal circuitry, differences in synaptic ultra-structures by electron microscopy, as well as electrophysiological perturbations of both glutamatergic and GABAergic transmission, as observed by altered frequency and amplitude of mEPSCs and mIPSCs. Furthermore, gene expression profiling by next-generation sequencing alone, or in combination with bacTRAP technology to study specifically Drd1a versus Drd2 medium spiny neurons, revealed that developmental CK1δ OE alters transcriptional homeostasis in the striatum, including specific alterations in Drd1a versus Drd2 neurons. These results led us to perform a fine molecular characterization of targeted gene networks and pathway analysis. Importantly, a large fraction of 92 genes identified by GWAS studies as associated with ADHD in humans are significantly altered in our mouse model. The multiple abnormalities described here might be responsible for synaptic alterations and lead to complex behavioral abnormalities. Collectively, CK1δ OE mice share characteristics typically associated with ADHD and should represent a valuable model to investigate the disease in vivo.

Exploring deficient emotion regulation in adult ADHD: electrophysiological evidence

Emotional dysregulation (ED) is being increasingly recognized as a core feature of attention-deficit/hyperactivity disorder (ADHD), but the pathophysiological underpinnings remain unclear. In this study, we provide meaningful electrophysiological evidence of ED in adult patients with ADHD (n = 39) compared to healthy controls (n = 40) by exploring the electrophysiological correlates of the emotion regulation strategies reappraisal, distraction, and expressive suppression. Event-related potentials (ERPs) were recorded during passive viewing of neutral and negative images, as well as during emotion regulation. The patients with ADHD exhibited increased frontal late positive potential (LPP) amplitudes during passive viewing of the aversive images and during emotion regulation. Compared with the healthy controls, a subgroup of medication-naïve patients with ADHD (n = 25) also exhibited larger centroparietal LPP amplitudes and provided more negative ratings of the aversive and neutral images. Both the frontal and centroparietal LPP amplitudes were associated with ADHD symptom severity. However, no significant deficit in LPP modulation during emotion regulation was found. These findings strongly support the clinical observation of increased emotional responsivity toward negative stimuli and difficulty during the implementation of emotion regulation strategies and thus encourage the implementation of emotion regulation modules in the treatment of adult patients with ADHD.

ADHD symptoms in healthy adults are associated with stressful life events and negative memory bias

Stressful life events, especially Childhood Trauma, predict ADHD symptoms. Childhood Trauma and negatively biased memory are risk factors for affective disorders. The association of life events and bias with ADHD symptoms may inform about the etiology of ADHD. Memory bias was tested using a computer task in N = 675 healthy adults. Life events and ADHD symptoms were assessed using questionnaires. The mediation of the association between life events and ADHD symptoms by memory bias was examined. We explored the roles of different types of life events and of ADHD symptom clusters. Life events and memory bias were associated with overall ADHD symptoms as well as inattention and hyperactivity/impulsivity symptom clusters. Memory bias mediated the association of Lifetime Life Events, specifically Childhood Trauma, with ADHD symptoms. Negatively biased memory may be a cognitive marker of the effects of Childhood Trauma on the development and/or persistence of ADHD symptoms.

Key Factors to Improve the Outcome of Retinal Reattachment Surgery in Proliferative Vitreoretinopathy and Proliferative Diabetic Retinopathy

INTRODUCTION

For management of complicated retinal detachments, a pars plana vitrectomy with temporary silicone oil (SO) fill is the method of choice. According to literature, the retinal redetachment rate varies between <10% and >70% with around 36% in our own group (retrospective data analysis, n = 119 eyes).

METHODS

The main goal was to reduce the retinal redetachment rate. Standard operating procedures (SOPs) and evaluation protocols (EVALPs) were developed to prospectively analyse risk factors. Lab analysis of SO was performed, and the role of surgical experience was evaluated and investigated with Eyesi®.

RESULTS

We achieved a significant reduction of the retinal redetachment rate (to 6.80%, n = 101, p = 0.002). After surgery with SO injection, neither further membrane peeling (in 16.5%) nor retinal laser coagulation (in 100%) during revision surgery had a significant effect on the reattachment rate (p = 0.167, p = 0.23), while extensive additional laser coagulation reduced visual acuity (p = 0.01). A 3-port approach had to be set up to complete SO removal. A difference in success rate depending on surgical experience was confirmed, and the performance in Eyesi correlated with that in the patients' eye.

CONCLUSIONS

A SOP- and EVALP-based management and new strategies to secure the surgical performance seem to be essential for successful surgery.

Executive attention control and emotional responding in attention-deficit/hyperactivity disorder--A functional MRI study

Background

There are suggestions that patients with attention-deficit/hyperactivity disorder (ADHD) show impairment in executive attention control and emotion regulation. This study investigated emotion regulation as a function of the recruitment of executive attention in patients with ADHD.

Methods

Thirty-five healthy children/adolescents (mean age = 13.91) and twenty-six children/adolescents with ADHD (mean age = 14.53) participated in this fMRI study. They completed the affective Stroop paradigm viewing positive, neutral and negative images under varying cognitive loads. A 3-way ANOVA (diagnosis-by-condition-by-emotion) was conducted on the BOLD response data. Following this, 2 3-way ANOVAs (diagnosis-by-condition-by-emotion) were applied to context-dependent psychophysiological interaction (gPPI) analyses generated from a dorsomedial frontal cortex and an amygdala seed (identified from the BOLD response ANOVA main effects of condition and emotion respectively).

Results

A diagnosis-by-condition interaction within dorsomedial frontal cortex revealed reduced recruitment of dorsomedial frontal cortex as a function of increased task demands in the children/adolescents with ADHD relative to healthy children/adolescents. The level of reduction in recruitment of dorsomedial frontal cortex was significantly correlated with symptom severity (total and hyperactivity) measured by Conner's Parent Report Scale in the children/adolescents with ADHD. In addition, analysis of gPPI data from a dorsomedial frontal cortex seed revealed significant diagnosis-by-condition interactions within lateral frontal cortex; connectivity between dorsomedial frontal cortex and lateral frontal cortex was reduced in the patients with ADHD relative to comparison youth during congruent and incongruent task trials relative to view trials. There were no interactions of group, or main effect of group, within the amygdala in the BOLD response ANOVA (though children/adolescents with ADHD showed increased responses to positive images within temporal cortical regions during task trials; identified by the diagnosis-by-condition-by-emotion interaction). However, analysis of gPPI data from an amygdala seed revealed decreased connectivity between amygdala and lentiform nucleus in the presence of emotional stimuli in children/adolescents with ADHD (diagnosis-by-emotion interaction).

Conclusion

The current study demonstrated disrupted recruitment of regions implicated in executive function and impaired connectivity within those regions in children/adolescents with ADHD. There were also indications of heightened representation of emotional stimuli in patients with ADHD. However, as the findings were specific for positive stimuli, the suggestion of a general failure in emotion regulation in ADHD was not supported.

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ADHD showed decreased dorsomedial frontal cortex activity with increased cognitive demand.

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Decreased dorsomedial frontal cortex activity was correlated with symptom severity of ADHD.

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Connectivity of dorsomedial frontal cortex–lateral frontal cortex was compromised in ADHD.

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ADHD showed increased activities in emotional responding areas to positive emotional stimuli.

Predicting Methylphenidate Response in ADHD Using Machine Learning Approaches

BACKGROUND

There are no objective, biological markers that can robustly predict methylphenidate response in attention deficit hyperactivity disorder. This study aimed to examine whether applying machine learning approaches to pretreatment demographic, clinical questionnaire, environmental, neuropsychological, neuroimaging, and genetic information can predict therapeutic response following methylphenidate administration.

METHODS

The present study included 83 attention deficit hyperactivity disorder youth. At baseline, parents completed the ADHD Rating Scale-IV and Disruptive Behavior Disorder rating scale, and participants undertook the continuous performance test, Stroop color word test, and resting-state functional MRI scans. The dopamine transporter gene, dopamine D4 receptor gene, alpha-2A adrenergic receptor gene (ADRA2A) and norepinephrine transporter gene polymorphisms, and blood lead and urine cotinine levels were also measured. The participants were enrolled in an 8-week, open-label trial of methylphenidate. Four different machine learning algorithms were used for data analysis.

RESULTS

Support vector machine classification accuracy was 84.6% (area under receiver operating characteristic curve 0.84) for predicting methylphenidate response. The age, weight, ADRA2A MspI and DraI polymorphisms, lead level, Stroop color word test performance, and oppositional symptoms of Disruptive Behavior Disorder rating scale were identified as the most differentiating subset of features.

CONCLUSIONS

Our results provide preliminary support to the translational development of support vector machine as an informative method that can assist in predicting treatment response in attention deficit hyperactivity disorder, though further work is required to provide enhanced levels of classification performance.

Emotional lability: the discriminative value in the diagnosis of attention deficit/hyperactivity disorder in adults

OBJECTIVE

The aim of this study is to assess the discriminative value of emotional lability (EL) in the diagnosis of adults with ADHD.

METHODS

A group of adults who met ADHD DSM-IV diagnostic criteria (n=589), a clinical control group (n=138) and a community control group (n=98) were compared in EL scores. SCID-I, SCID-II and CAADID were used to select subjects. The specific subscale on EL of the Conners Adult ADHD Rating Scale (CAARS) was used to evaluate EL.

RESULTS

An analysis of the covariance was carried out in order to explore the association between EL, ADHD and comorbidity. The group factor (ADHD, clinical or community group) and the comorbidity factor (presence or absence of other psychiatric disorders different from ADHD) showed to be significant on EL intensity (group: F=81.78 p=0.000; comorbidity: F=25.48 p=0.000). However, no significant differences were found in the group × comorbidity interaction (F=1.006, p=0.366). EL showed a sensitivity of 87.1% and a specificity of 46.6% in discriminating between ADHD patients and subjects with other psychiatric disorders.

CONCLUSION

EL is specifically related to ADHD and this association is not explained for the presence of other psychiatric disorders. The presence of comorbid disorders is only related to a major intensity of EL.

The Amygdala's Neurochemical Ratios after 12 Weeks Administration of 20 mg Long-acting Methylphenidate in Children with Attention Deficit and Hyperactivity Disorder: A Pilot Study Using (1)H Magnetic Resonance Spectroscopy

Objective

Recent pediatric studies have suggested a correlation between decreased amygdala volume and attention deficit and hyperactivity disorder (ADHD) symptoms, including the emotional dysregulation. To investigate the hypothesis that medication treatment of ADHD specifically improves amygdala function, we used ¹H magnetic resonance spectroscopy (MRS) to study the effect of 12 weeks of treatment with daily 20 mg long-acting methylphenidate on the Glu/Cr, NAA/Cr, Cho/Cr, and mI/Cr ratios in the amygdala of medication-naïve children with ADHD.

Methods

This was a prospective study, using a pre- and post-test design, on a single group of 21 children (average age 8.52 years, 17 males and 4 females) diagnosed with ADHD. Low Time Echo MRS scans sampled voxels of interest (1.5×1.5×2.0) from both the right and left amygdala.

Results

There was significant clinical improvement after 12 weeks of treatment with 20 mg long-acting methylphenidate. On 1H MRS, there were no statistical significant differences of NAA/Cr ratio, Cho/Cr ratio, mI/Cr ratio before and after 12 weeks administration of 20 mg long-acting methylphenidate both in the right and left amygdala. In addition, Glu/Cr ratio decreased 14.1% in the right amygdala (p=0.029) and 11.4% in the left amygdala (p=0.008). Standardized mean effect sizes ranged from 0.14-0.32.

Conclusion

The findings are consistent with the possibility that hyperglutamatergic processes in the amygdale are related to the hyperactive-impulsive symptoms of ADHD.

Abnormal amygdala functional connectivity associated with emotional lability in children with attention-deficit/hyperactivity disorder

OBJECTIVE

A substantial proportion of children with attention-deficit/hyperactivity disorder (ADHD) also display emotion regulation deficits manifesting as chronic irritability, severe temper outbursts, and aggression. The amygdala is implicated in emotion regulation, but its connectivity and relation to emotion regulation in ADHD has yet to be explored. The purpose of this study was to examine the relationship between intrinsic functional connectivity (iFC) of amygdala circuits and emotion regulation deficits in youth with ADHD.

METHOD

Bilateral amygdala iFC was examined using functional magnetic resonance imaging in 63 children with ADHD, aged 6 to 13 years. First, we examined the relationship between amygdala IFC and parent ratings of emotional lability (EL) in children with ADHD. Second, we compared amygdala iFC across subgroups of children with ADHD and high EL (n = 18), ADHD and low EL (n = 20), and typically developing children (TDC), all with low EL (n = 19).

RESULTS

Higher EL ratings were associated with greater positive iFC between the amygdala and rostral anterior cingulate cortex in youth with ADHD. EL scores were also negatively associated with iFC between bilateral amygdala and posterior insula/superior temporal gyrus. Patterns of amygdala-cortical iFC in ADHD participants with low EL were not different from the comparison group, and the effect sizes for these comparisons were smaller than those for the trend-level differences observed between the high-EL and TDC groups.

CONCLUSIONS

In children with ADHD and a range of EL, deficits in emotion regulation were associated with altered amygdala-cortical iFC. When comparing groups that differed on ADHD status but not EL, differences in amygdala iFC were small and nonsignificant, highlighting the specificity of this finding to emotional deficits, independent of other ADHD symptoms.

Altered cingulate and amygdala response towards threat and safe cues in attention deficit hyperactivity disorder

BACKGROUND

Emotional dysregulation is becoming increasingly recognized as an important feature of attention deficit hyperactivity disorder (ADHD). In this study, two experiments were conducted investigating the neural response to either verbally instructed fear (IF) or uninstructed (classically conditioned) fear (UF) using the skin conductance response (SCR) and functional magnetic resonance imaging (fMRI).

METHOD

In the conditioning phase of the UF experiment (17 ADHD and 17 healthy controls), subjects experienced an unconditioned stimulus (UCS, unpleasant electrodermal stimulation) paired with a former neutral conditioned stimulus (CS+), whereas a control stimulus (CS-) was never paired with the UCS. In the subsequent test phase, only the CS+ and the CS- were presented. In the IF experiment (13 ADHD and 17 healthy controls), subjects were only told that an independently experienced UCS might occur together with the CS+ but not the CS- during testing. No UCS was presented.

RESULTS

Groups did not detectably differ in SCR or neural responses to UF. In IF, ADHD patients showed a trend-line decreased SCR and significantly decreased activation of the dorsal anterior cingulate cortex (dACC), a region prominently involved in fear responding, to the CS+. This was accompanied by higher amygdala activation to the CS-.

CONCLUSIONS

During IF, ADHD patients showed deficits in regions centrally involved in fear learning and expression in terms of diminished CS+-related dACC and increased CS--related amygdala signals. This suggests an impaired processing of verbally transmitted aversive information, which is central for conveying fear information in social contexts. This result extends the growing literature on emotional alterations in ADHD.

Current hypotheses on the mechanisms of alcoholism

Chronic use of alcohol results in progressive changes to brain and behavior that often lead to the development of alcohol dependence and alcoholism. Although the mechanisms underlying the development of alcoholism remain to be fully elucidated, diminished executive functioning due to hypoactive prefrontal cortex executive control and hyperactive limbic system anxiety and negative emotion might contribute mechanistically to the shift from experimental use to alcoholism and dependence. In the chapter that follows, behavioral deficits associated with cortical dysfunction and neurodegeneration will be related to the behavioral characteristics of alcoholism (e.g., diminished executive function, impulsivity, altered limbic modulation). We will provide evidence that alterations in cyclic AMP-responsive element binding protein (CREB: neurotrophic) and NF-κB (neuroimmune) signaling contribute to the development and persistence of alcoholism. In addition, genetic predispositions and an earlier age of drinking onset will be discussed as contributing factors to the development of alcohol dependence and alcoholism. Overall chronic ethanol-induced neuroimmune gene induction is proposed to alter limbic and frontal neuronal networks contributing to the development and persistence of alcoholism.

Sleep promotes consolidation of emotional memory in healthy children but not in children with attention-deficit hyperactivity disorder

Fronto-limbic brain activity during sleep is believed to support the consolidation of emotional memories in healthy adults. Attention deficit-hyperactivity disorder (ADHD) is accompanied by emotional deficits coincidently caused by dysfunctional interplay of fronto-limbic circuits. This study aimed to examine the role of sleep in the consolidation of emotional memory in ADHD in the context of healthy development. 16 children with ADHD, 16 healthy children, and 20 healthy adults participated in this study. Participants completed an emotional picture recognition paradigm in sleep and wake control conditions. Each condition had an immediate (baseline) and delayed (target) retrieval session. The emotional memory bias was baseline–corrected, and groups were compared in terms of sleep-dependent memory consolidation (sleep vs. wake). We observed an increased sleep-dependent emotional memory bias in healthy children compared to children with ADHD and healthy adults. Frontal oscillatory EEG activity (slow oscillations, theta) during sleep correlated negatively with emotional memory performance in children with ADHD. When combining data of healthy children and adults, correlation coefficients were positive and differed from those in children with ADHD. Since children displayed a higher frontal EEG activity than adults these data indicate a decline in sleep-related consolidation of emotional memory in healthy development. In addition, it is suggested that deficits in sleep-related selection between emotional and non-emotional memories in ADHD exacerbate emotional problems during daytime as they are often reported in ADHD.

Emotional dysregulation in adult ADHD: What is the empirical evidence?

Attention deficit/hyperactivity disorder (ADHD) is a common psychiatric disorder characterized by symptoms of inattention, hyperactivity and impulsivity. There is an ongoing discussion whether symptoms of emotional dysregulation should be added to the conceptualization of ADHD in order to describe the psychopathology of ADHD more precisely, at least in adult patients. Symptoms of emotional dysregulation are well defined and seem to be distinct factors of the psychopathology of adult ADHD. Assessment of this psychopathological dimension has shown sufficient reliability and validity. Empirical studies have confirmed a high prevalence of this psychopathological feature in adults with ADHD that compares to the frequency of the ADHD core symptoms, inattention, hyperactivity and impulsivity. Evidence is given that emotional dysregulation has an independent effect on social problems associated with ADHD in adult life. Moreover, pharmacological and psychotherapeutic interventions help to ameliorate emotional dysregulation together with symptoms of inattention and hyperactivity/impulsivity. Thus, there is growing evidence that emotional dysregulation might be recognized as a core feature of ADHD.

Abnormal functional connectivity in children with attention-deficit/hyperactivity disorder

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is typically characterized by symptoms of inattention and hyperactivity/impulsivity, but there is increased recognition of a motivation deficit too. This neuropathology may reflect dysfunction of both attention and reward-motivation networks.

METHODS

To test this hypothesis, we compared the functional connectivity density between 247 ADHD and 304 typically developing control children from a public magnetic resonance imaging database. We quantified short- and long-range functional connectivity density in the brain using an ultrafast data-driven approach.

RESULTS

Children with ADHD had lower connectivity (short- and long-range) in regions of the dorsal attention (superior parietal cortex) and default-mode (precuneus) networks and in cerebellum and higher connectivity (short-range) in reward-motivation regions (ventral striatum and orbitofrontal cortex) than control subjects. In ADHD children, the orbitofrontal cortex (region involved in salience attribution) had higher connectivity with reward-motivation regions (striatum and anterior cingulate) and lower connectivity with superior parietal cortex (region involved in attention processing).

CONCLUSIONS

The enhanced connectivity within reward-motivation regions and their decreased connectivity with regions from the default-mode and dorsal attention networks suggest impaired interactions between control and reward pathways in ADHD that might underlie attention and motivation deficits in ADHD.