October 1, 2024

Understanding Hyperactivity in Women with ADHD: Absent or Hidden?

ADHD (Attention-Deficit/Hyperactivity Disorder) has often been seen as a condition that mainly affects boys, especially when it comes to hyperactivity. However, a new study challenges this idea by showing that hyperactivity is also common in women with ADHD, pointing out the need for better diagnoses.

The study included 13,179 adults with ADHD and 1,910 adults without it. Researchers measured how active participants were using a special test, looking at both "provoked" activity (activity triggered by specific tasks that puts the brain “online”) and "basal" activity (resting or natural activity levels when the brain is “offline”). The study included almost an equal number of men and women, with the goal of finding out if there were any differences between the sexes in ADHD diagnosis, particularly in hyperactivity.

The results were eye-opening. Although men generally showed higher levels of activity when the brain was online, both men and women with ADHD had much higher levels of both offline and online activity compared to people without ADHD. Specifically, those with ADHD had about twice the resting activity and three times the provoked activity compared to those without the disorder.

A key finding was that women with ADHD had hyperactivity levels similar to men with ADHD. This goes against the common belief that women with ADHD don’t show hyperactivity or show it less. It suggests that hyperactivity in women may be missed or misunderstood due to societal expectations or differences in behavior.

These findings have big implications. They suggest that the way we currently understand ADHD, especially hyperactivity in women, might be wrong. By recognizing that women with ADHD can have significant hyperactivity, doctors can diagnose ADHD more accurately. This could lead to earlier treatment and better management of ADHD in women, which might also lower the chances of related problems like anxiety or depression.

The study highlights the importance of thinking about gender differences when diagnosing and treating ADHD. By realizing that hyperactivity isn't just a "male" trait, we can better support everyone with ADHD and ensure they get the right care. As research on ADHD continues, it’s important to challenge old assumptions and take a more inclusive approach to understanding and treating the disorder.

Wettstein R, Navarro Ovando V, Pirgon E, Kroesen J, Wettstein K, Kroesen H, Mathôt R, Dumont G. Absent or Hidden? Hyperactivity in Females With ADHD. J Atten Disord. 2024 Aug 19:10870547241273152. doi: 10.1177/10870547241273152. Epub ahead of print. PMID: 39161237.

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News Tuesday: Fidgeting and ADHD

A recent study delved into the connection between fidgeting and cognitive performance in adults with Attention-Deficit/Hyperactivity Disorder. Recognizing that hyperactivity often manifests as fidgeting, the researchers sought to understand its role in attention and performance during cognitively demanding tasks. They designed a framework to quantify meaningful fidgeting variables using actigraphy devices.

(Note: Actigraphy is a non-invasive method of monitoring human rest/activity cycles. It involves the use of a small, wearable device called an actigraph or actimetry sensor, typically worn on the wrist, similar to a watch. The actigraph records movement data over extended periods, often days to weeks, to track sleep patterns, activity levels, and circadian rhythms. In this study, actigraphy devices were used to measure fidgeting by recording the participants' movements continuously during the cognitive task. This data provided objective, quantitative measures of fidgeting, allowing the researchers to analyze its relationship with attention and task performance.)

The study involved 70 adult participants aged 18-50, all diagnosed with ADHD. Participants underwent a thorough screening process, including clinical interviews and ADHD symptom ratings. The analysis revealed that fidgeting increased during correct trials, particularly in participants with consistent reaction times, suggesting that fidgeting helps sustain attention. Interestingly, fidgeting patterns varied between early and later trials, further highlighting its role in maintaining focus over time.

Additionally, a correlation analysis validated the relevance of the newly defined fidget variables with ADHD symptom severity. This finding suggests that fidgeting may act as a compensatory mechanism for individuals with ADHD, aiding in their ability to maintain attention during tasks requiring cognitive control.

This study provides valuable insights into the role of fidgeting in adults with ADHD, suggesting that it may help sustain attention during challenging cognitive tasks. By introducing and validating new fidget variables, the researchers hope to standardize future quantitative research in this area. Understanding the compensatory role of fidgeting can lead to better management strategies for ADHD, emphasizing the potential benefits of movement for maintaining focus.

July 16, 2024

NEWS TUESDAY: Controllability in ADHD

Recent advancements in brain network analysis may help researchers better understand the dysfunctions of the complex neural networks associated with ADHD.

Controllability refers to the ability to steer the brain's activity from one state to another. In simpler terms, it’s about how different regions of the brain can influence and regulate each other to maintain normal functioning or respond to tasks and stimuli. 

The Study at a Glance

Researchers examined functional MRI (fMRI) data from 143 healthy individuals and 102 ADHD patients, they focused on a specific metric called the node controllability index (CA-scores). This metric helps quantify how different brain regions contribute to overall brain function.

Key Findings

The study revealed that individuals with ADHD exhibit significantly different CA-scores in various brain regions compared to healthy controls. These regions include:

  • Rolandic operculum
  • Superior medial orbitofrontal cortex
  • Insula
  • Posterior cingulate gyrus
  • Supramarginal gyrus
  • Angular gyrus
  • Precuneus
  • Heschl gyrus
  • Superior temporal gyrus

These areas are crucial for processes such as decision-making, sensory processing, and attention.

This new study suggests that the controllability index might be a more effective tool in identifying brain regions that work differently in those with ADHD. This means that controllability could provide a clearer picture of the brain networks associated with ADHD.

Although ADHD still cannot be diagnosed with this type of imaging, studies such as this highlight the complexity of the disorder and provide new avenues for future research. 

August 6, 2024

Non-stimulant Medications for Adults with ADHD: An Overview

NEW STUDY: Non-stimulant Medications for Adults with ADHD: An Overview

Attention-Deficit/Hyperactivity Disorder (ADHD) in adults is commonly treated with stimulant medications such as methylphenidate and amphetamines. However, not all patients respond well to these stimulants or tolerate them effectively. For such cases, non-stimulant medications provide an alternative treatment approach.

Recent research by Brancati et al. reviews the efficacy and safety of non-stimulant medications for adult ADHD. Atomoxetine, a well-studied non-stimulant, has shown significant effectiveness in treating ADHD symptoms in adults. The review highlights the importance of considering dosage, treatment duration, safety, and the presence of psychiatric comorbidities when prescribing atomoxetine.

Additionally, certain antidepressants, including tricyclic compounds, bupropion, and viloxazine, which possess noradrenergic or dopaminergic properties, have demonstrated efficacy in managing adult ADHD. Antihypertensive medications, especially guanfacine, have also been found effective. Other medications like memantine, metadoxine, and mood stabilizers show promise, whereas treatments like galantamine, antipsychotics, and cannabinoids have not yielded positive results.

The expert opinion section of the review emphasizes that while clinical guidelines primarily recommend atomoxetine as a second-line treatment, several other non-stimulant options can be utilized to tailor treatments based on individual patient needs and comorbid conditions. Despite these advancements, the authors call for further research to develop and refine more personalized treatment strategies for adults with ADHD.

This review underscores the growing landscape of non-stimulant treatment options, offering hope for more personalized and effective management of ADHD in adults.

June 25, 2024

Population Study Links ADHD Medication with Reduced Criminality, Suicides, Automotive Crashes, Substance Abuse

Many studies have shown that ADHD is associated with increased risks of suicidal behavior, substance misuse, injuries, and criminality. As we often discuss in our blogs, treatments for ADHD include medication and non-medication options, such as CBT (Cognitive Behavioral Therapy). While non-drug approaches are often used for young children or mild cases of ADHD, medications – both stimulants and non-stimulants – are common for adolescents and adults. 

Global prescriptions for ADHD drugs have risen significantly in recent years, raising questions about their safety and effectiveness. Randomized controlled trials have demonstrated that medication can help reduce the core symptoms of ADHD. However, research from these trials still offers limited or inconclusive insights into wider and more significant clinical outcomes, such as suicidal behavior and substance use disorder.

An international study team conducted a nationwide population study using the Swedish national registers. Sweden has a single-payer national health insurance system, which covers nearly every resident, enabling such studies. The researchers examined all Swedish residents aged 6 to 64 who received their first ADHD diagnosis between 2007 and 2018. Analyses of criminal behavior and transport accidents focused on a subgroup aged 15 to 64, since individuals in Sweden must be at least 15 years old to be legally accountable for crimes or to drive.

The team controlled for confounding factors, including demographics (age at ADHD diagnosis, calendar year, sex, country of birth, highest education (using parental education for those under 25), psychiatric and physical diagnoses, dispensations of psychotropic drugs, and health care use (outpatient visits and hospital admissions for both psychiatric and non-psychiatric reasons).

Time-varying covariates from the previous month covered diagnoses, medication dispensations, and healthcare use. During the study, ADHD treatments licensed in Sweden included amphetamine, atomoxetine, dexamphetamine, guanfacine, lisdexamphetamine, and methylphenidate.

After accounting for covariates, individuals diagnosed with ADHD who received medication treatment showed better outcomes than those who did not. Specifically:

-Suicidal behaviors dropped by roughly 15% in both first-time and recurrent cases.

-Initial criminal activity decreased by 13%, with repeated offences falling by 25%.

-Substance abuse initiation declined by 15%, while recurring substance abuse was reduced

by 25%.

-First automotive crashes were down 12%, and subsequent crashes fell by 16%.

There was no notable reduction in first-time accidental injuries, and only a marginally significant 4% decrease in repeated injuries.

The team concluded, “Drug treatment for ADHD was associated with beneficial effects in reducing the risks of suicidal behaviours, substance misuse, transport accidents, and criminality, but not accidental injuries when considering first event rate. The risk reductions were more pronounced for recurrent events, with reduced rates for all five outcomes.”

Meta-analysis of Non-invasive Brain Stimulation Finds Limited Evidence of Efficacy

Background: 

Pharmacotherapies, such as methylphenidate, are highly effective for short-term ADHD management, but issues remain with medication tolerability and adherence. Some patients experience unwanted side effects from stimulant medications, leaving them searching for alternative ADHD treatments. Alternative treatments such as cognitive training, behavioral therapies, psychological interventions, neurofeedback, and dietary changes have, so far, shown limited success. Thus, there is a critical need for non-pharmacological options that boost neurocognitive performance and address core ADHD symptoms.

First— What Are NIBS (Non-Invasive Brain Stimulation) Techniques?

Non-invasive brain stimulation (NIBS) techniques, including transcranial direct current stimulation (tDCS), transcranial random noise stimulation (tRNS), transcranial alternating current stimulation (tACS), and repetitive transcranial magnetic stimulation (rTMS) are generating growing attention within the scientific community. 

NIBS techniques are methods that use external stimulation, such as magnets or electrical currents, to affect brain activity without any invasive procedures. In transcranial alternating current stimulation (tACS), for example, small electrodes are placed on the scalp of the patient, and a weak electrical current is administered. 

The theory behind these techniques is that when a direct current is applied between two or more electrodes placed on specific areas of the head, it makes certain neurons more or less likely to fire. This technique has been successfully used to treat conditions like depression and anxiety, and to aid recovery from stroke or brain injury. 

The Study: 

Previous meta-analyses have produced conflicting indications of efficacy. A Chinese research team consisting of sports and rehabilitative medicine professionals has just published a network meta-analysis to explore this further, through direct comparison of five critical outcome domains: inhibitory control, working memory, cognitive flexibility, inattention, hyperactivity and impulsivity.

To be included, randomized controlled trials needed to have participants diagnosed with ADHD, use sham control groups, and assess ADHD symptoms and executive functions – such as inhibitory control, working memory, cognitive flexibility, inattention, hyperactivity, and impulsivity – using standardized tests.

A total of thirty-seven studies encompassing 1,615 participants satisfied the inclusion criteria. It is worth noting, however, that the authors did not specify the number of randomized controlled trials nor the number of participants included in each arm of the network meta-analysis.

Furthermore, the team stated, “We checked for potential small study effects and publication bias by conducting comparison-adjusted funnel plots,” but did not share their findings. They also did not provide information on outcome variation (heterogeneity) among the RCTs.

Results:

Ultimately, none of the interventions produced significant improvements in ADHD symptoms, whether in inattention symptoms or hyperactivity/impulsivity symptoms.  Likewise, none of the interventions produced significant improvements in inhibitory control. Some tDCS interventions enhanced working memory and cognitive flexibility, but details about trial numbers and participants were missing. The team concluded, “none of the NIBS interventions significantly improved inhibitory control compared to sham controls. … In terms of working memory, anodal tDCS over the left DLPFC plus cathodal tDCS over the right DLPFC … and anodal tDCS over the right inferior frontal cortex (rIFC) plus cathodal tDCS over the right supraorbital area ... were associated with significant improvements compared to sham stimulation. For cognitive flexibility, only anodal tDCS over the left DLPFC plus cathodal tDCS over the right supraorbital area demonstrated a statistically significant benefit relative to sham. ... Compared to the sham controls, none of the NIBS interventions significantly improved inattention. ... Compared to the sham controls, none of the NIBS interventions significantly improved hyperactivity and impulsivity.”

How Should We Interpret These Results?

In a word, skeptically.

If one were to read just the study’s abstract, which states, “The dual-tDCS and a-tDCS may be considered among the preferred NIBS interventions for improving cognitive function in ADHD”, it might seem that the takeaway from this study is that this combination of brain stimulation techniques might be a viable treatment option for those with ADHD. Upon closer inspection, however, the results do not suggest that any of these methods significantly improve ADHD symptoms. Additionally, this study suffers from quite a few methodological flaws, so any results should be viewed critically.

October 31, 2025

Meta-analysis of Transcranial Direct Current Stimulation Still Yields Little Sign of Efficacy

Background:

Despite recommendations for combined pharmacological and behavioral treatment in childhood ADHD, caregivers may avoid these options due to concerns about side effects or the stigma that still surrounds stimulant medications. Alternatives like psychosocial interventions and environmental changes are limited by questionable effectiveness for many patients. Increasingly, patients and caregivers are seeking other therapies, such as neuromodulation – particularly transcranial direct current stimulation (tDCS). 

tDCS seeks to enhance neurocognitive function by modulating cognitive control circuits with low-intensity scalp currents. There is also evidence that tDCS can induce neuroplasticity. However, results for ADHD symptom improvement in children and adolescents are inconsistent. 

The Method:

To examine the evidence more rigorously, a Taiwanese research team conducted a systematic search focusing exclusively on randomized controlled trials (RCTs) that tested tDCS in children and adolescents diagnosed with ADHD. They included only studies that used sham-tDCS as a control condition – an essential design feature that prevents participants from knowing whether they received the active treatment, thereby controlling for placebo effects. 

The Results:

Meta-analysis of five studies combining 141 participants found no improvement in ADHD symptoms for tDCS over sham-TDCS. That held true for both the right and left prefrontal cortex. There was no sign of publication bias, nor of variation (heterogeneity) in outcomes among the RCTs.  

Meta-analysis of six studies totaling 171 participants likewise found no improvement in inattention symptoms, hyperactivity symptoms, or impulsivity symptoms for tDCS over sham-TDCS. Again, this held true for both the right and left prefrontal cortex, and there was no sign of either publication bias or heterogeneity. 

Most of the RCTs also performed follow-ups roughly a month after treatment, on the theory that induced neuroplasticity could lead to later improvements. 

Meta-analysis of four RCTs combining 118 participants found no significant improvement in ADHD symptoms for tDCS over sham-TDCS at follow-up. This held true for both the right and left prefrontal cortex, with no sign of either publication bias or heterogeneity. 

Meta-analysis of five studies totaling 148 participants likewise found no improvement in inattention symptoms or hyperactivity symptoms for tDCS over sham-TDCS at follow-up. AS before, this was true for both the right and left prefrontal cortex, with no sign of either publication bias or heterogeneity. 

The only positive results came from meta-analysis of the same five studies, which reported a medium effect size improvement in impulsivity symptoms at follow-up. Closer examination showed no improvement from stimulation of the right prefrontal cortex, but a large effect size improvement from stimulation of the left prefrontal cortex

Interpretation: 

It is important to note that the one positive result was from three RCTs combining only 90 children and adolescents, a small sample size. Moreover, when only one of sixteen combinations yields a positive outcome, that begins to look like p-hacking for a positive result. 

In research, scientists use something called a “p-value” to determine if their findings are real or just due to chance. A p-value below 0.05 (or 5%) is considered “statistically significant,” meaning there's less than a 5% chance the result happened by pure luck. 

When testing twenty outcomes by this standard, one would expect one to test positive by chance even if there is no underlying association. In this case, one in 16 comes awfully close to that. 

To be sure, the research team straightforwardly reported all sixteen outcomes, but offered an arguably over-positive spin in their conclusion: “Our study only showed tDCS-associated impulsivity improvement in children/adolescents with ADHD during follow-ups and anode placement on the left PFC. ... our findings based on a limited number of available trials warrant further verification from large-scale clinical investigations.” 

October 24, 2025