The area of mental health is pretty dinamic and ever-changing field, where new informations and insights are gained every day and old assumptions pretty easy turn into no more then a myth. To keep you up to date, I decided to compile the most important findings on ADHD in the year 2012. I tried to keep it simple for everybody to understand regardless of educational background, and if you want to know more the are links on every study cited in the article. This is the first review I made and I plan to make a whole series of reviewing posts about most important scientific discoveries in 2012. In the next few days I’ll cover topics of depression, anxiety, bipolar disorder, schizophrenia and more, so don’t forget to check it out. I hope we all learn something from this.
1. Toward Systems Neuroscience of ADHD: A Meta-Analysis of 55 fMRI Studies
The earlier model of ADHD pathopsychology were focused solely on prefrontal-striatal circuits but this study significantly extends these models. As this review found, ADHD is related to much broader range of dysfunctions than previously thought and includes dysfunction in multiple neuronal systems involved in higher-level cognitive functions, sensorimotor processes and visual systems. In ADHD children,frontoparietal network involved in executive functioning and ventral attentional network involved in attention were under-activated, while somatomotor networks were hyperactivated in comparison with non-ADHD children. In adults, ADHD-related hypoactivation was predominant in the frontoparietal system, while ADHD-related hyperactivation was present in the visual, dorsal attention, and default networks.
TL;DR: ADHD severely alters your brain circuits, and not only behind your forehead as previously thought, but all around the lobe: your high cognitive functions, attention, motor and visual systems are all affected.
2. A review of fronto-striatal and fronto-cortical brain abnormalities in children and adults with Attention Deficit Hyperactivity Disorder (ADHD) and new evidence for dysfunction in adults with ADHD during motivation and attention
An increasing number of studies suggests that structural and functional abnormalities, such as those in study 1 here,persist into adulthood despite a relative symptomatic improvement in the adult form of the disorder. This research presents new data that support this ADHD-persistance hypothesis. Researchers followed young adults with ADHD for 20 years, since their childhood and the results are dysfunctions in lateral fronto-striatoparietal regions, as well as in ventromedial orbitofrontal regions during reward, suggesting dysfunctions in cognitive-attentional as well as motivational neural networks. The authors conclude that their „review supported by the new data therefore suggest that both adult and childhood ADHD are associated with brain abnormalities in fronto-cortical and fronto-subcortical systems that mediate the control of cognition and motivation. The brain deficits in ADHD therefore appear to be multi-systemic and to persist throughout the lifespan.“
TL;DR: Your ADHD symptoms may improve as you get older, but unfortunately they won’t disapper. The reason is, ofcourse, all in neurology: some brain regions of ADHD people are sructurally damaged and time doesn’t fix them.
3. Fatty acids in ADHD: plasma profiles in a placebo-controlled study of Omega 3/6 fatty acids in children and adolescents
Seventy five ADHD children and adolescents were given Omega 3/6 (Equazen eye q) or placebo for three months, followed by three months of open phase Omega 3/6 for all. Omega 3, Omega 6 and Omega3/6 ratio were measured at baseline, 3 and 6 months. Of course, Omega group showed improvements in all measured parameters related to ADHD, in comparison to placebo group, both after 3 and 6 months. Compared to placeboists, the 6-month Omegists had significantly greater Omega 3 increase at 3 months and decrease in Omega 3/6 ratio at 3 and 6 months. Omega 3/6 supplementation had a clear impact on fatty acid composition of plasma phosphatidyl choline in active versus placebo group, and the fatty acid changes appear to be associated with treatment response. The most pronounced and long-lasting changes for treatment responders compared to non-responders were in the n-6/n-3 ratio. Here’s the link to the article.
TL;DR: Take fish oil or eat more fish, they contain Omega 3 fatty acids which will help you with your ADHD greatly.
4. Supplementation with flax oil and vitamin C improves the outcome of Attention Deficit Hyperactivity Disorder (ADHD)
This study evaluated the effects of alpha linolenic acid (ALA)-rich nutritional supplementation in the form of flax oil and antioxidant emulsion on blood fatty acids composition and behavior in children with ADHD. Flax oil supplementation corresponding to 200 mg ALA content along with 25 mg Vitamin C were given to the participants twice a day for 3 months. And the results were spectacular: individual scores for Inattention, Impulsivity, Restlessness and Self-Control, all symptoms of ADHD, reduced significantly. There’s one drawback of this study: a placebo group was not included which makes it unclear whether flax oil and flax oil only was responsible for this reduction of symptoms. Instead, the pre and post supplementation measures within the subjects were used which is also good measure so I think this study can be trusted.
TL;DR: Along with fish oil, use flax oil too. It’s highly beneficial for ADHD.
5. Reinforcement, Dopamine and Rodent Models in Drug Development for ADHD
Current treatment with psychostimulants and nonstimulants is effective, but their mechanism of action beyond the cellular level is not well understood. There’s a bald suggestion that altered reinforcement mechanisms are a fundamental characteristic of ADHD. The article shows that a deficit in the transfer of dopamine signals from established positive reinforcers to cues that predict such reinforcers may underlie these altered reinforcement mechanisms, and in turn explain key symptoms of ADHD. The neural substrates controlling the excitation and inhibition of dopamine neurons during the transfer process should be concern in future development of ADHD drugs.
TL;DR: It seems that being unable to recognize cues that predict positive reinforcement explains key symptoms of ADHD. Dopamine is main suspect for this and future drugs should focus on fixing neural substrates of dopamine.
6. Sex, ADHD symptoms, and smoking outcomes: An integrative model
Both females and individuals with Attention-Deficit/Hyperactivity Disorder (ADHD) have been found to be at increased risk for a range of smoking outcomes, and recent empirical findings have suggested that women with ADHD may be particularly vulnerable to nicotine dependence.
This article proposes following hypotheses related to sex, ADHD, and smoking: (1) individuals with ADHD have altered functioning of the dopamine reward system, which diminishes their ability to efficiently form conditioned associations based on environmental contingencies; these deficits are partially ameliorated by nicotine; (2) nicotine interacts with estrogen and the dopamine reward system to increase the positive and negative reinforcement value of smoking in female smokers; (3) in adult females with ADHD, ovarian hormones interact with the dopamine reward system to exacerbate ADHD-related deficits in the capacity to form conditioned associations; and (4) during different phases of the menstrual cycle, nicotine and ovarian hormones may interact differentially with the dopamine reward processing system to affect the type and value of reinforcement smoking provides for women with ADHD.
TL;DR: ADHD are at greater risk of nicotine dependence. Nicotine interacts with estrogen to increase reinforcement value of smoking, and smoking ameliorates some ADHD related dysfunctions. Thus, ADHD females have the greatest risk of nicotine addiction.
7. Offspring ADHD as a Risk Factor for Parental Marital Problems: Controls for Genetic and Environmental Confounds
Offspring ADHD predicted parental divorce and marital conflict. The associations were also robust when comparing differentially exposed identical twins to control for unmeasured genetic and environmental factors, when controlling for measured maternal and paternal psychopathology, when restricting the sample based on timing of parental divorce and ADHD onset, and when controlling for other forms of offspring psychopathology. Each of these controls rules out alternative explanations for the association. The results of the current study converge with those of prior research in suggesting that factors directly associated with offspring ADHD increase parental marital problems.
TL;DR: You are more likely to get divorced if your child suffers from ADHD.
8. A randomized controlled trial of CBT therapy for adults with ADHD with and without medication
This was a secondary analysis comparing 23 participants randomized to CBT and Dextroamphetamine vs. 25 participants randomized to CBT and placebo. Both groups showed robust improvement in both symptoms and functioning, but the use of medication did not significantly improve outcome over and above use of CBT and placebo. This study replicates previous work demonstrating that CBT is an effective treatment for ADHD in adults.
TL;DR: Cognitive-behavioral therapy can help you deal with ADHD without medication
9. Practitioner Review: What have we learnt about the causes of ADHD?
This is a review of articles published since 1997 that deals with risk factors related to ADHD and discusses the likelihood that these risks are causal for developing ADHD. The main results are summarized as followes: no single risk factor explains ADHD. Both inherited and noninherited factors contribute and their effects are interdependent. ADHD is familial and heritable. Research into the inherited and molecular genetic contributions to ADHD suggest an important overlap with other neurodevelopmental problems, notably, autism spectrum disorders. Having a biological relative with ADHD, large, rare copy number variants, some small effect size candidate gene variants, extreme early adversity, pre and postnatal exposure to lead and low birth weight/prematurity have been most consistently found as risk factors, but none are yet known to be definitely causal. As far as environmental risk are concerned, they can only be regarded as correlates.
TL;DR: ADHD is complex disorder. We know some risk factors for developing ADHD but the causal factors remain mysterious.