and in autism: The case of hesitation marker usage in Dutch-speaking autistic preschoolers.

English-speaking autistic children use the hesitation marker less often than non-autistic children but use at a similar rate. It is unclear why this is the case. We employed a sample of Dutch-speaking children from the Preschool Brain Imaging and Behavior Project to examine hesitation markers in autistic and non-autistic preschoolers with the aim to 1) make a crosslinguistic comparison of hesitation marker usage and 2) examine hypotheses regarding the underlying linguistic mechanisms of hesitation markers: the symptom hypothesis and the signal hypothesis.

Parent attitudes towards data sharing in developmental science.

Background: Data sharing in developmental science is increasingly encouraged, supported by funder and publisher mandates for open data access. Data sharing can accelerate discovery, link researchers with high quality analytic expertise to researchers with large datasets and democratise the research landscape to enable researchers with limited funding to access large sample sizes. However, there are also significant privacy and security concerns, in addition to conceptual and ethical considerations.

Three year outcomes in infants with a family history of autism and/or attention deficit hyperactivity disorder.

Background: Most research on early outcomes in infants with a family history (FH) of autism has focussed on categorically defined autism, although some have language and developmental delays. Less is known about outcomes in infants with a FH of attention deficit hyperactivity disorder (ADHD).

Methods: Infants with and without a FH of autism and/or ADHD, due to a first-degree relative with either or both conditions, were recruited at 5 or 10 months.

From the lab to the field: acceptability of using electroencephalography with Indian preschool children.

: Measurement of social and cognitive brain development using electroencephalography (EEG) offers the potential for early identification of children with elevated risk of developmental delay. However, there have been no published reports of how acceptable EEG technology is to parents and children within communities, especially in low-resource contexts such as in low and middle income countries (LMICs), which is an important question for the potential scalability of these assessments. We use a mixed-methods approach to examine whether EEG assessments are acceptable to children and their caregivers in a low resource community setting in India.

Cortical responses to social stimuli in infants at elevated likelihood of ASD and/or ADHD: A prospective cross-condition fNIRS study.

Autism spectrum disorders (ASD) and attention-deficit hyperactivity disorder (ADHD) are highly prevalent neurodevelopmental conditions that often co-occur and present both common and distinct neurodevelopmental profiles. Studying the developmental pathways leading to the emergence of ASD and/or ADHD symptomatology is crucial in understanding neurodiversity and discovering the mechanisms that underpin it. This study used functional near-infrared spectroscopy (fNIRS) to investigate differences in cortical specialization to social stimuli between 4- to 6-month-old infants at typical and elevated likelihood of ASD and/or ADHD.

Using the Infant Sibling-Design to Explore Associations Between Autism and ADHD Traits in Probands and Temperament in the Younger Siblings.

The purpose of the current study was to use the infant sibling design to explore whether proband traits of autism and ADHD could provide information about their infant sibling's temperament. This could help us to gain information about the extent to which infant temperament traits are differentially associated with autism and ADHD traits. We used parent-ratings of autistic traits and ADHD traits (CRS-3) in older siblings diagnosed with autism (age range 4 to 19 years), and their infant siblings' temperament traits (IBQ) at 9 months of age in 216 sibling pairs from two sites (BASIS, UK, and EASE, Sweden) to examine associations across siblings.

Infant excitation/inhibition balance interacts with executive attention to predict autistic traits in childhood.

Background: Autism is proposed to be characterised by an atypical balance of cortical excitation and inhibition (E/I). However, most studies have examined E/I alterations in older autistic individuals, meaning that findings could in part reflect homeostatic compensation. To assess the directionality of effects, it is necessary to examine alterations in E/I balance early in the lifespan before symptom emergence.

Altered theta-beta ratio in infancy associates with family history of ADHD and later ADHD-relevant temperamental traits.

Background: Uncovering the neural mechanisms that underlie symptoms of attention deficit hyperactivity disorder (ADHD) requires studying brain development prior to the emergence of behavioural difficulties. One new approach to this is prospective studies of infants with an elevated likelihood of developing ADHD.

Methods: We used a prospective design to examine an oscillatory electroencephalography profile that has been widely studied in both children and adults with ADHD - the balance between lower and higher frequencies operationalised as the theta-beta ratio (TBR).

INTERSTAARS: Attention training for infants with elevated likelihood of developing ADHD: A proof-of-concept randomised controlled trial.

Attention-deficit/hyperactivity disorder (ADHD) is first diagnosed during middle childhood, when patterns of difficulty are often established. Pre-emptive approaches that strengthen developing cognitive systems could offer an alternative to post-diagnostic interventions. This proof-of-concept randomised controlled trial (RCT) tested whether computerised gaze-based attention training is feasible and improves attention in infants liable to develop ADHD.

Behavioural Measures of Infant Activity but Not Attention Associate with Later Preschool ADHD Traits.

Mapping infant neurocognitive differences that precede later ADHD-related behaviours is critical for designing early interventions. In this study, we investigated (1) group differences in a battery of measures assessing aspects of attention and activity level in infants with and without a family history of ADHD or related conditions (ASD), and (2) longitudinal associations between the infant measures and preschool ADHD traits at 3 years. Participants ( = 151) were infants with or without an elevated likelihood for ADHD (due to a family history of ADHD and/or ASD).

Use of a physiologically-based pharmacokinetic model to explore the potential disparity in nicotine disposition between adult and adolescent nonhuman primates.

The widespread use and high abuse liability of tobacco products has received considerable public health attention, in particular for youth, who are vulnerable to nicotine addiction. In this study, adult and adolescent squirrel monkeys were used to evaluate age-related metabolism and pharmacokinetics of nicotine after intravenous administration. A physiologically-based pharmacokinetic (PBPK) model was created to characterize the pharmacokinetic behaviors of nicotine and its metabolites, cotinine, trans-3'-hydroxycotinine (3'-OH cotinine), and trans-3'-hydroxycotinine glucuronide (3'-OH cotinine glucuronide) for both adult and adolescent squirrel monkeys.

Positron emission tomography (PET) imaging of nicotine-induced dopamine release in squirrel monkeys using [F]Fallypride.

Background: Nicotine, the principal psychoactive tobacco constituent, is thought to produce its reinforcing effects via actions within the mesolimbic dopamine (DA) system. The objective of the current study was to examine the effect of nicotine on DA D/D receptor availability in the nonhuman primate brain with the use of the radioligand [F]fallypride and positron emission tomography (PET).

Methods: Ten adult male squirrel monkeys were used in the current study.

Attention training for infants at familial risk of ADHD (INTERSTAARS): study protocol for a randomised controlled trial.

Background: Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder that can negatively impact on an individual's quality of life. It is pathophysiologically complex and heterogeneous with different neuropsychological processes being impaired in different individuals. Executive function deficits, including those affecting attention, working memory and inhibitory control, are common.

An intravenous self-administration procedure for assessing the reinforcing effects of hallucinogens in nonhuman primates.

Introduction: Self-administration procedures are the gold standard for investigating the reinforcing effects of drugs. The notable exception to good correspondence between laboratory self-administration studies and human drug taking behavior has historically been the classic hallucinogens.

Method: The present study used a well-established daily access procedure, followed by a novel intermittent access procedure, to investigate the reinforcing effects of LSD in baboons.

The Reinforcing Effects of Nicotine in Humans and Nonhuman Primates: A Review of Intravenous Self-Administration Evidence and Future Directions for Research.

Introduction: Cigarette smoking is largely driven by the reinforcing properties of nicotine. Intravenous (IV) self-administration procedures are the gold standard for investigating the reinforcing effects of psychoactive drugs. The goal of this review was to examine the results of published investigations of the reinforcing effects of nicotine measured using IV self-administration procedures in humans and nonhuman primates.

Effects of adolescent treatment with nicotine, harmane, or norharmane in male Sprague-Dawley rats.

The initiation of tobacco use occurs most often in adolescence and may be especially detrimental as the adolescent brain is undergoing substantial development. In addition to nicotine, there are over 9000 other compounds present in tobacco products, including the β-carbolines harmane and norharmane. The present study aimed to determine the long-term effects of adolescent exposure to nicotine (NIC), harmane (HAR), or norharmane (NOR) on locomotor activity, learning and memory, anxiety-like behavior, motor coordination, and monoamine/metabolite concentrations in the striatum and nucleus accumbens of male Sprague-Dawley rats.

Physical dependence on gamma-hydroxybutrate (GHB) prodrug 1,4-butanediol (1,4-BD): time course and severity of withdrawal in baboons.

Background: 1,4-Butanediol (1,4-BD) is a gamma-hydroxybutyrate (GHB) pro-drug, with multiple commercial uses, and a drug of abuse. Although there are case reports of a withdrawal syndrome following 1,4-BD use, no studies have evaluated the physical dependence potential of 1,4-BD and characterized the time course of withdrawal.

Methods: Vehicle and then 1,4-BD were administered continuously 24 h/day via intragastric catheters in male baboons (Papio anubis, n=3).

Behavioral effects and pharmacokinetics of (±)-3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) after intragastric administration to baboons.

(±)-3,4-Methylenedioxymethamphetamine (MDMA, "Ecstasy") is a popular drug of abuse. We aimed to characterize the behavioral effects of intragastric MDMA in a species closely related to humans and to relate behavioral effects to plasma MDMA and metabolite concentrations. Single doses of MDMA (0.

Self-administration of gamma-hydroxybutyric acid (GHB) precursors gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD) in baboons.

Rationale: Gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD) are gamma-hydroxybutyrate (GHB) pro-drugs and drugs of abuse.

Objective: Given the reports of abuse, and the ease at which GBL and 1,4-BD may be obtained, we investigated the reinforcing effects of GBL (n = 5) and 1,4-BD (n = 4) in baboons using IV self-administration procedures.

Methods: Sessions ran 24 h/day.

Smoking cessation program with exercise improves cardiovascular disease biomarkers in sedentary women.

Background: Several cardiovascular disease (CVD) biomarkers sensitive to tobacco exposure have been identified, but how tobacco use cessation impacts them is less clear. We sought to investigate the effects of a smoking cessation program with an exercise intervention on CVD biomarkers in sedentary women.

Methods: This is a cohort study on a subsample of a 2×2 factorial randomized controlled trial (RCT) (exercise setting: home vs.

Metabolism and disposition of 3,4-methylenedioxymethamphetamine ("ecstasy") in baboons after oral administration: comparison with humans reveals marked differences.

The baboon is potentially an attractive animal for modeling 3,4-methylenedioxymethamphetamine (MDMA) effects in humans. Baboons self-administer MDMA, are susceptible to MDMA neurotoxicity, and are suitable for positron emission tomography, the method most often used to probe for MDMA neurotoxicity in humans. Because pharmacokinetic equivalence is a key feature of a good predictive animal model, we compared the pharmacokinetics of MDMA in baboons and humans.

Intravenous self-administration of γ-hydroxybutyrate (GHB) in baboons.

Background: Abuse of gamma-hydroxybutyrate (GHB) poses a public health concern. In previous studies, intravenous (IV) self-administration of GHB doses up to 10 mg/kg was not maintained in non-human primates under limited-access conditions, which was inconsistent with the usual good correspondence between drugs abused by humans and those self-injected by laboratory animals.

Methods: Self-administration of GHB was studied in 10 baboons using procedures standard for our laboratory to assess drug abuse liability.