Inattentive Subtype Research Articles

The Co-Occurrence of Autism Spectrum Disorder in Children With ADHD

Objective: Children with ADHD frequently present with autism spectrum disorder (ASD) symptomatology, yet there is a notable gap in the treatment needs of this subpopulation, including whether the presence of ASD may be associated with more severe ADHD symptoms. Method: Data from the 2014 National Survey of the Diagnosis and Treatment of ADHD and Tourette Syndrome (n = 2,464) were used to compare children diagnosed with ADHD and ASD with children with ADHD, but not ASD. Children were classified as needing treatment if it was received or their parents reported it was needed, but not received. Results: Approximately one in eight children currently diagnosed with ADHD was also diagnosed with ASD. Children diagnosed with both disorders had greater treatment needs, more co-occurring conditions, and were more likely to have a combined hyperactive/impulsive and inattentive ADHD subtype. Conclusion: These findings highlight the complexity of children diagnosed with both ADHD and ASD.

16p11: Description of the behavioral and morphological phenotype of a “mirror” syndrome

Objective: Copy number variations (CNVs) in the 16p11.2 gene region are translated into different morphological and neurobehavioral phenotypes. The main objective of our study is to describe these differences according to the type of CNV. It is proposed as a secondary objective the design of a protocol of assessment and follow-up for these patients. Methods: Retrospective descriptive study in patients with CNVs in 16p11.2 diagnosed in a Tertiary Hospital using Array-CGH. We collected anthropometric data, dysmorphic features, and performed neuropsychological assessments (ASD, ADHD, intellectual and neurodevelopment screening). Results: A total of 9 patients with 16p11 CNVs were studied. 6 cases with a deletion, being 100% of these de novo; and 3 cases with a duplication, being 67% of the cases inherited. Patients with deletions were overweight / obese and macrocephalus, while patients with duplications present a normal BMI and microcephaly. Clinical manifestations observed in the patients studied included ophthalmological disorders (22%), psychomotor retardation (67%), mild intellectual deficit (56%), autism spectrum disorder (22%) and ADHD (78%). All of the patients that exceed cut point in SNAP -IV in the sample were carriers of a deletion, predominating in them the inattentive subtype ADHD. Conclusion: CNV carriers in the 16p11.2 gene region present mirror anthropometric phenotypes and the most frequently associated conditions were psychomotor development delay, ASD, and ADHD. Inattentive type ADHD is the most commonly observed in patients with deletions, and no significant differences in neuropsychological profile were observed at other levels depending on the type of CNVs. Taking into account the above, it is proposed to carry out an assessment and follow-up protocol that includes a standardized medical history, a comprehensive physical examination including ophthalmologic examination and complementary examinations to rule out intellectual deficit, ASD and ADHD.

Prevalence and clinical correlates of insomnia in adults with attention-deficit hyperactivity disorder.

To investigate the prevalence of insomnia in adults with Attention-deficit hyperactivity disorder (ADHD) and its association with clinical subtypes, current ADHD symptoms, and stimulant treatment. We obtained diagnostic information, symptom rating scales and treatment history from clinically ascertained adult ADHD patients diagnosed according to DSM-IV criteria (n = 268, mean age 38.1 years) and randomly selected population controls (n = 202, mean age 36.5 years). The Bergen Insomnia Scale (BIS) was used to measure insomnia. ADHD symptom domains were self-rated using the Adult ADHD Self-Rating Scale. Insomnia was far more frequent among adults with ADHD (66.8%) than in the population controls (28.8%) (P < 0.001). Insomnia was more common in adults with the combined subtype than in those with the inattentive subtype (79.7% and 55.6%, respectively) (P = 0.003). For self-reported current ADHD symptoms, inattention was strongly correlated to insomnia. Patients currently using stimulant treatment for ADHD reported a lower total insomnia score compared to patients without medication (P < 0.05). Insomnia was highly prevalent among adults with ADHD. The lower insomnia score in patients on current stimulant treatment suggests that stimulant treatment is not associated with worsening of insomnia symptoms in adult ADHD patients.

Variation in the Oxytocin Receptor Gene Is Associated With Social Cognition and ADHD

Objective: Children with ADHD show substantial deficits in social cognitive abilities. Oxytocin, mediated through its specific receptor (OXTR), is involved in the regulation of social behavior and social cognition. Method: The entire coding sequence of the human OXT and OXTR genes were sequenced to identify mutations and single nucleotide polymorphisms (SNPs) in 151 children with ADHD (ADHD-combined, n = 51; inattentive subtype, n = 50; ADHD-C plus conduct disorder [CD], n = 50; 11-18 years) and 100 healthy controls. Results: We examined the association of three detected SNPs of OXTR with social cognition deficits. A significant association was shown between the children with ADHD and children with CT/TT genotypes of rs4686302 (χ2 = 3.695; p = .037). ADHD children with CT/TT genotype for the OXTR rs4686302 performed significantly lower on the facial emotion recognition task than those with CC genotype. Conclusion: OXTR rs4686302 polymorphism was shown to be a genetic marker in social cognition deficits in ADHD children.

RANZCP 2017 Book of Abstracts

Background: Attention-deficit hyperactivity disorder (ADHD) is one of the most common mental health disorders in children. Limitations of behavioural interventions and pharmacological treatment have led to the development of other novel interventions. Neurofeedback has shown promise in improving not only inattention symptoms but also impulsivity/hyperactivity symptoms. A feed-forward mechanism has been proposed to be more feasible in the treatment of ADHD as it trains individuals to harness their ability to pay attention and also shows promise in improving impulsivity symptoms. Objectives: The aim of the current study is to investigate the impact of a novel intervention using (feed-forward) brain-to-computer interface (BCI) technology on an objective measure of attention and impulsivity in children with ADHD. Methods: A total of 172 children aged 6 to 12 years (mean = 8.63, standard deviation = 1.51) with a clinical diagnosis of ADHD, inattentive or combined subtype were recruited. Participants were randomized into the waitlist-control or intervention group. Participants in the intervention group underwent 24 sessions of brain-to-computer interface technology (BCI) intervention over a period of 8 weeks, whereas participants in the control group did not receive any intervention. The Conners’ Continuous Performance Test, second edition (CPT-II) was administered to the participants before and after the treatment. Findings: Analysis was conducted for the intervention and control groups at weeks 1 and 8.Conclusions: Results will be discussed with a view to inform future research.

IL-6 and TNF-α in unmedicated adults with ADHD: Relationship to cortisol awakening response

There is preliminary evidence that the immune system’s cytokines may have impact on ADHD in children. Nevertheless, studies exploring the possible role of pro-inflammatory cytokines in adults with ADHD are lacking. This study aimed to assess differences in serum IL-6 and TNF-α between patients and controls and their possible relationship to resting cortisol.108 adults with ADHD (DSM-IV), 44 inattentive and 64 combined, age ranging between 18 and 55 years, and 27 healthy controls were included. Major psychiatric disorders and organic comorbidities were excluded. Serum samples for IL-6 and TNF-α and salivary samples to assess cortisol awakening response were collected on the same day. Analysis of variance was applied to study differences in IL-6 and TNF-α between groups. Pearson correlations were used to study associations between IL-6, TNF-α, and CAR.There were no significant differences in serum IL-6 or TNF-α levels between patients and controls or between combined and inattentive patients. Negative associations between IL-6 (r=−0.386, p=0.020), TNF-α (r=−0.372, p=0.023) and cortisol awakening response were found in the inattentive subtype, whereas no association was seen in the combined subtype. A negative correlation between IL-6 and cortisol was also present in the control group (r=−0.44, 0.030).The peripheral pro-inflammatory markers, IL-6 and TNF-α, do not appear to be primarily involved in ADHD in adults, although the role of other inflammatory markers cannot be ruled out. The differences regarding the association between IL-6 and TNF-α and morning cortisol response suggest possible underlying neurobiological differences between the inattentive or combined patients that merit further studies.

Latent Class Analysis of ADHD Symptoms in Korean Children and Adolescents

Objective: The objective of this study was to conduct latent class analysis (LCA) of ADHD symptoms to characterize the underlying structure of ADHD. Method: Participants were recruited from September 2012 to January 2015 from the Department of Psychiatry of Asan Medical Center, Seoul, Korea. Diagnoses of ADHD and comorbid psychiatric disorders were confirmed with the Kiddie–Schedule for Affective Disorders and Schizophrenia–Present and Lifetime Version (K-SADS-PL). We performed LCA of ADHD symptoms in those who had (n = 141, age = 8.1 ± 2.3 years, 106 boys) and did not have (n = 82, age = 9.1 ± 2.5 years, 40 boys) ADHD. Results: A three-class solution was found to be the best model, revealing classes of children with mostly combined and hyperactive/impulsive subtypes of ADHD (Class 1), non-ADHD (Class 2), and inattentive subtype of ADHD (Class 3). Conclusion: The three-class solution with LCA supports a two-factor two-class structure of ADHD symptoms.

Regional brain network organization distinguishes the combined and inattentive subtypes of Attention Deficit Hyperactivity Disorder.

Attention Deficit Hyperactivity Disorder (ADHD) is characterized clinically by hyperactive/impulsive and/or inattentive symptoms which determine diagnostic subtypes as Predominantly Hyperactive-Impulsive (ADHD-HI), Predominantly Inattentive (ADHD-I), and Combined (ADHD-C). Neuroanatomically though we do not yet know if these clinical subtypes reflect distinct aberrations in underlying brain organization.We imaged 34 ADHD participants defined using DSM-IV criteria as ADHD-I (n = 16) or as ADHD-C (n = 18) and 28 matched typically developing controls, aged 8–17 years, using high-resolution T1 MRI. To quantify neuroanatomical organization we used graph theoretical analysis to assess properties of structural covariance between ADHD subtypes and controls (global network measures: path length, clustering coefficient, and regional network measures: nodal degree). As a context for interpreting network organization differences, we also quantified gray matter volume using voxel-based morphometry.Each ADHD subtype was distinguished by a different organizational profile of the degree to which specific regions were anatomically connected with other regions (i.e., in “nodal degree”). For ADHD-I (compared to both ADHD-C and controls) the nodal degree was higher in the hippocampus. ADHD-I also had a higher nodal degree in the supramarginal gyrus, calcarine sulcus, and superior occipital cortex compared to ADHD-C and in the amygdala compared to controls. By contrast, the nodal degree was higher in the cerebellum for ADHD-C compared to ADHD-I and in the anterior cingulate, middle frontal gyrus and putamen compared to controls. ADHD-C also had reduced nodal degree in the rolandic operculum and middle temporal pole compared to controls. These regional profiles were observed in the context of no differences in gray matter volume or global network organization.Our results suggest that the clinical distinction between the Inattentive and Combined subtypes of ADHD may also be reflected in distinct aberrations in underlying brain organization.

Relationship between Impulsivity and Serum Oxytocin in Male Children and Adolescents with Attention-Deficit and Hyperactivity Disorder: A Preliminary Study

Here we aimed to determine the relationship between oxytocin levels and impulsivity, which is an important aspect at Attention Deficit Hyperactivity Disorder (ADHD) clinics. The study population comprised 40 ADHD patients diagnosed based on the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version, without other psychiatric disorders and chronic diseases aged between 8 and 15 years. The control group comprised 40 healthy, age-matched, male children and adolescents who voluntarily participated in the study. Patients and controls filled the Barratt impulsivity scale-11 (BIS-11). Ten cubic centimeters of blood was collected at 8 am for determining serum oxytocin levels. ELISA kits were used to measure serum oxytocin levels in a biochemistry laboratory. The obtained data were evaluated using appropriate statistical methods. In this study, compared with the control group, the impulsivity scores were significantly higher and serum oxytocin levels were lower in the ADHD group (52.5±18.1 and 37.62±9.0, respectively, p<0.001). Serum oxytocin levels showed a negative correlation with impulsivity and attention subscale scores of BIS-11 in the ADHD group. ADHD and impulsivity, which comprise an aspect of ADHD, may be associated with oxytocin. Serum oxytocin levels may contribute to inattention subtypes of impulsivity observed in ADHD.

Stimulus control in two rodent models of attention-deficit/hyperactivity disorder

The spontaneously hypertensive (SHR/NCrl) rat from Charles River is one of the most widely used models of the combined subtype of Attention-Deficit/Hyperactivity Disorder (ADHD-C). Although often used as its control strain, the Wistar Kyoto (WKY/NCrl) from Charles River has been proposed as a model of the predominately inattentive subtype of ADHD (ADHD-PI). In Experiment 1 SHR/NCrl, WKY/NCrl, and Wistar (WI; the progenitor strain for the two models) rats were trained on a left→right lever-press sequence in the presence of light discriminative stimuli that signaled the active lever in the sequence. In subsequent conditions the discriminative light cues were removed or reversed. WKY/NCrl accuracy remained relatively stable across cue light transitions. SHR/NCrl and WI accuracy was more disrupted when light cues were removed or reversed—an indication that behavior of the WKY/NCrl rats may not have come under control of the discriminative light cues as it did for the other strains, but relied more on past behavior and spatial cues. In Experiment 2, all three strains were exposed to a response-initiated fixed-interval (RIFI) 8-s schedule of reinforcement. In RIFI schedules behavior must be timed from a past instance of the target response. Replicating previous work, timing during the FI was roughly equivalent across the three strains; however, latencies to initiate the FI were significantly longer for SHR/NCrl than WKY/NCrl and WI rats, suggesting SHR/NCrl behavior was less sensitive to the first-response:food contingency in the RIFI schedule. These findings identify differences in stimulus control between the three strains and may help determine the efficacy of SHR/NCrl and WKY/NCrl as models of ADHD subtypes in humans.

Adult attention-deficit/hyperactivity disorder: Associations between subtype and lifetime substance use – a clinical study

ADHD is the one of the most prevalent childhood disorders and has been associated with impairments persisting into adulthood. Specifically, childhood ADHD is an independent clinical risk factor for the development of later substance use disorders (SUD). Moreover, adults who meet diagnostic criteria for ADHD have shown high rates of comorbid SUDs. Few studies, however, have reported on the relationship between ADHD subtypes and SUD in adult samples. The purpose of this study was to characterize a clinical sample of adults with ADHD and to identify possible associations between ADHD subtypes, lifetime substance use, and if ADHD subtypes may be preferentially associated with specific substances of abuse. We recruited 413 adult ADHD patients, performed an evaluation of their ADHD and conducted an interview on their use of psychotropic substances. Complete data was obtained for 349 patients. Lifetime substance abuse or dependence was 26% and occasional use was 57% in this sample. The inattentive subtype was significantly less likely to abuse or be dependent on cocaine than the combined subtype. Our findings underscore the high rate of comorbidity between substance use and ADHD in adults. The more frequent abuse/dependence of cocaine by adult patients with hyperactive-impulsive symptoms should be kept in mind when treating this patient group.

Adult attention-deficit/hyperactivity disorder: Associations between subtype and lifetime substance use – a clinical study

ADHD is the one of the most prevalent childhood disorders and has been associated with impairments persisting into adulthood. Specifically, childhood ADHD is an independent clinical risk factor for the development of later substance use disorders (SUD). Moreover, adults who meet diagnostic criteria for ADHD have shown high rates of comorbid SUDs. Few studies, however, have reported on the relationship between ADHD subtypes and SUD in adult samples. The purpose of this study was to characterize a clinical sample of adults with ADHD and to identify possible associations between ADHD subtypes, lifetime substance use, and if ADHD subtypes may be preferentially associated with specific substances of abuse. We recruited 413 adult ADHD patients, performed an evaluation of their ADHD and conducted an interview on their use of psychotropic substances. Complete data was obtained for 349 patients. Lifetime substance abuse or dependence was 26% and occasional use was 57% in this sample. The inattentive subtype was significantly less likely to abuse or be dependent on cocaine than the combined subtype. Our findings underscore the high rate of comorbidity between substance use and ADHD in adults. The more frequent abuse/dependence of cocaine by adult patients with hyperactive-impulsive symptoms should be kept in mind when treating this patient group.

Comparing Auditory Noise Treatment with Stimulant Medication on Cognitive Task Performance in Children with Attention Deficit Hyperactivity Disorder: Results from a Pilot Study.

Background: Recent research has shown that acoustic white noise (80 dB) can improve task performance in people with attention deficits and/or Attention Deficit Hyperactivity Disorder (ADHD). This is attributed to the phenomenon of stochastic resonance in which a certain amount of noise can improve performance in a brain that is not working at its optimum. We compare here the effect of noise exposure with the effect of stimulant medication on cognitive task performance in ADHD. The aim of the present study was to compare the effects of auditory noise exposure with stimulant medication for ADHD children on a cognitive test battery. A group of typically developed children (TDC) took the same tests as a comparison.Methods: Twenty children with ADHD of combined or inattentive subtypes and twenty TDC matched for age and gender performed three different tests (word recall, spanboard and n-back task) during exposure to white noise (80 dB) and in a silent condition. The ADHD children were tested with and without central stimulant medication.Results: In the spanboard- and the word recall tasks, but not in the 2-back task, white noise exposure led to significant improvements for both non-medicated and medicated ADHD children. No significant effects of medication were found on any of the three tasks.Conclusion: This pilot study shows that exposure to white noise resulted in a task improvement that was larger than the one with stimulant medication thus opening up the possibility of using auditory noise as an alternative, non-pharmacological treatment of cognitive ADHD symptoms.

Sluggish Cognitive Tempo in a Child and Adolescent Clinical Outpatient Setting.

Sluggish cognitive tempo (SCT) symptoms have largely emerged from investigations of attention-deficit/hyperactivity disorder (ADHD). Recent research has demonstrated the relevance of SCT symptoms in the field of clinical child and adolescent psychiatry. The goal of this research was to study the symptoms of SCT in a clinical child and adolescent sample and to define its features and comorbid conditions. We reviewed 834 clinical records of patients referred to Child and Adolescent Mental Health Services and examined SCT symptoms and their relation with sociodemographic data, clinical diagnosis, comorbid conditions, Child Behavior Checklist dimensions, and intelligence quotient. Of the 515 patients (age range, 4 to 17 y, 62.5% male) for whom a fully completed Child Behavior Checklist for Children and Adolescents was available, 20.8% showed high levels of SCT symptoms. SCT symptoms were strongly associated with age, internalizing symptoms, learning disabilities, and ADHD inattentive subtype (ADHD-I). No significant correlations with intelligence quotient were found. We concluded that SCT symptoms are highly prevalent in a clinical sample, and that these symptoms might be related to the difficulties that some individuals have in responding to demands in their environments, such as academic or social demands, as they increase over time.

Is emotion recognition the only problem in ADHD? effects of pharmacotherapy on face and emotion recognition in children with ADHD.

The objectives of this study were to evaluate both face and emotion recognition, to detect differences among attention deficit and hyperactivity disorder (ADHD) subgroups, to identify effects of the gender and to assess the effects of methylphenidate and atomoxetine treatment on both face and emotion recognition in patients with ADHD. The study sample consisted of 41 male, 29 female patients, 8-15years of age, who were diagnosed as having combined type ADHD (N=26), hyperactive/impulsive type ADHD (N=21) or inattentive type ADHD (N=23) but had not previously used any medication for ADHD and 35 male, 25 female healthy individuals. Long-acting methylphenidate (OROS-MPH) was prescribed to 38 patients, whereas atomoxetine was prescribed to 32 patients. The reading the mind in the eyes test (RMET) and Benton face recognition test (BFRT) were applied to all participants before and after treatment. The patients with ADHD had a significantly lower number of correct answers in child and adolescent RMET and in BFRT than the healthy controls. Among the ADHD subtypes, the hyperactive/impulsive subtype had a lower number of correct answers in the RMET than the inattentive subtypes, and the hyperactive/impulsive subtype had a lower number of correct answers in short and long form of BFRT than the combined and inattentive subtypes. Male and female patients with ADHD did not differ significantly with respect to the number of correct answers on the RMET and BFRT. The patients showed significant improvement in RMET and BFRT after treatment with OROS-MPH or atomoxetine. Patients with ADHD have difficulties in face recognition as well as emotion recognition. Both OROS-MPH and atomoxetine affect emotion recognition. However, further studies on the face and emotion recognition are needed in ADHD.

Sex- and Subtype-Related Differences in the Comorbidity of Adult ADHDs

Objective: Comorbidity in adult ADHD (aADHD) has been investigated in a large number of studies using varying research approaches with divergent results. In contrast, there is limited information about sex- or subtype-related differences from studies with small sample size. Method: A large sample of 910 individuals (458 males, 452 females) affected with aADHD was recruited at a tertiary referral center. All probands underwent a four-step procedure for diagnosing aADHD, including the Structured Clinical Interview of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) Axis I disorders to assess comorbidity. This study will provide additional information regarding the co-morbidity of Axis I disorders in the currently largest clinical referral sample. However, the main objective of this study is to gain information about sex- or subtype-related differences. Results: Affected females show higher rates of mood (61% vs. 49%), anxiety (32% vs. 22%), and eating disorders (16% vs. 1%) than affected males, while substance use disorders were more frequent in affected males (45% vs. 29%), which mirrors sex differences in prevalence in the general population. There were hardly any relevant differences in comorbidities between subtypes, with the exception of the inattentive subtype having an especially low prevalence of panic disorder. Comorbidity in general and substance use disorders in particular, but not sex or subtype, were highly predictive of lower psychosocial status. Conclusion: Sex-related differences in the comorbidity of aADHD are more pronounced than subtype-related differences.

Neurofeedback as an Intervention to Improve Reading Achievement in Students with Attention Deficit Hyperactivity Disorder, Inattentive Subtype

Author(s): La Marca, Jeffry P; O'Connor, Rollanda E | Abstract: Research consistently demonstrates that attention deficits have a deleterious effect on academic achievement. Impairments in attention, and not hyperactivity/impulsivity, are associated with learning difficulties and academic problems in students with attention-deficit/hyperactivity disorder (ADHD). To date, most studies have focused on symptoms of hyperactivity/impulsivity, with little research being conducted on interventions for students with ADHD, inattentive subtype. This study examines the use of neurofeedback as an intervention to improve reading achievement in a public school setting. A multiple-baseline-across-participants single-case model was used to assess five fourth-grade students who received 40 daily sessions of neurofeedback. Following the intervention, improvements were observed on objective measures of attention: a continuous performance test (Integrated Visual and Auditory Continuous Performance Test [IVA+Plus]) and/or a testof shifting attention (CNS Vital Signs, Shifting Attention Test [CNS-VS, SAT]). Results on tests of reading fluency revealed little change, although participants demonstrated gains on a measure of reading comprehension (Gray Oral Reading Tests–Fifth Edition [GORT-5]). Results suggest that neurofeedback helped participants to become more accurately engaged with the text with more focused attention to content. Thus, neurofeedback may be a viable option to assist children with attention deficits for improving both attention and reading achievement.

Double-dissociation between the mechanism leading to impulsivity and inattention in Attention Deficit Hyperactivity Disorder: A resting-state functional connectivity study

Two core symptoms characterize Attention Deficit Hyperactivity Disorder (ADHD) subtypes: inattentiveness and hyperactivity–impulsivity. While previous brain imaging research investigated ADHD as if it was a homogenous condition, its two core symptoms may originate from different brain mechanisms. We, therefore, hypothesized that the functional connectivity of cortico-striatal and attentional networks would be different between ADHD subtypes. We studied 165 children (mean age 10.93 years; age range, 7–17 year old) diagnosed as having ADHD based on their revised Conner's rating scale score and 170 typical developing individuals (mean age 11.46 years; age range, 7–17 year old) using resting state functional fMRI. Groups were matched for age, IQ and head motion during the MRI acquisition. We fractionated the ADHD group into predominantly inattentive, hyperactive–impulsive and combined subtypes based on their revised Conner's rating scale score. We then analyzed differences in resting state functional connectivity of the cortico-striatal and attentional networks between these subtypes. We found a double dissociation of functional connectivity in the cortico-striatal and ventral attentional networks, reflecting the subtypes of the ADHD participants. Particularly, the hyperactive–impulsive subtype was associated with increased connectivity in cortico-striatal network, whereas the inattentive subtype was associated with increased connectivity in the right ventral attention network. Our study demonstrated for the first time a right lateralized, double dissociation between specific networks associated with hyperactivity–impulsivity and inattentiveness in ADHD children, providing a biological basis for exploring symptom dimensions and revealing potential targets for more personalized treatments.

Consequences of low or moderate prenatal ethanol exposures during gastrulation or neurulation for open field activity and emotionality in mice

In a previous study we used a mouse model for ethanol exposure during gastrulation or neurulation to investigate the effects of modest and occasional human drinking during the 3rd or 4th week of pregnancy (Schambra et al., 2015). Pregnant C57Bl/6J mice were treated by gavage during gastrulation on gestational day (GD) 7 or neurulation on GD8 with 2 doses 4h apart of either 2.4 or 2.9g ethanol/kg body weight, resulting in peak blood ethanol concentrations (BECs) of 104 and 177mg/dl, respectively. We found that mice exposed to the low dose on either day were significantly delayed in their neonatal sensorimotor development. In the present study, we tested the same cohort of mice in an open field as juveniles on postnatal day (PD) 23–25 and as young adults on PD65–67 for prenatal ethanol effects on exploration and emotionality with measures of activity, rearing, grooming and defecation. We evaluated the effects of dose, sex, day of treatment and day of birth by multiple regression analyses.We found that, compared to the respective gavage controls, juvenile mice that had been prenatally exposed to the low BEC on either GD7 or GD8 were significantly hypoactive on the first 2 test days, reared significantly more on the last 2 test days, and groomed and defecated significantly more on all 3 test days. Only mice that had been treated on GD7 remained hypoactive as adults. Juvenile mice prenatally exposed to the moderate BEC on GD7 groomed significantly more, while those exposed on GD8 reared and defecated significantly more. Sex differences were highly significant in adult control mice, with control males less active and more emotional than females. Similar, but smaller, sex differences were also evident in adults exposed to ethanol prenatally. Persistence into later life of a deleterious effect of premature birth (i.e., birth on GD19 rather than GD20) on weight and behavior was not consistently supported by these data.Importantly, mice shown previously to be delayed in sensorimotor development as neonates, in the present study demonstrated hypoactivity and increased emotionality in open field behaviors as juveniles, and those mice exposed during gastrulation remained hypoactive as adults. Thus, we propose that the delayed motor development, hypoactivity and emotionality we observed in mice exposed to a low BEC during gastrulation or neurulation may relate to an attention deficit–activity disorder in humans, possibly the inattentive subtype, or Sluggish Cognitive Tempo (SCT). We further discuss concerns about occasional light or moderate alcohol consumption during the 3rd or 4th week of human pregnancy.

Brain structural features that characterize the inattentive and combined subtypes of ADHD

Brain structural features that characterize the inattentive and combined subtypes of ADHD