ADHD is a neurodevelopmental disorder.
(World Health Organization, 2022)ADHD is rooted in the brain's structure as it develops.
Symptoms will most often first appear (onset) in the early developmental period or middle childhood (3-12 years old).
Symptoms persist at least into adolescence in 50-80% of cases, and through adulthood in a 50-70% of cases (Barkley, 2006).
There are no true "cures" for ADHD because the disorder is built into the brain's structure.
ADHD is heavily rooted in genetics, heritability is 0.80 (Barkley, 2006).
ADHD is very common.
3-7% of children and 2-5% of adults experience ADHD (Barkley, 2006).
ADHD is more common in males, especially in childhood.
The ratio is around 3:1 in children and 2:1 (or lower) in adults (Barkley, 2006).
ADHD symptoms may be categorized as predominately inattentive or predominantly hyperactive-impulsive.
(World Health Organization, 2022)Hyperactive symptoms are more common in early childhood and often diminish into adolescence.
Inattentive symptoms are less common early childhood and more common adolescence.
ADHD may cause struggles or delays with:
(World Health Organization, 2022)Self control or delayed gratification.
Consistent intrinsic motivation (self-motivation).
Physical or mental restlessness.
Attention and persistence in task completion.
Working memory.
Sense of time.
Development of internal language/self-talk.
This can cause struggles with self-reflection and self-regulation
Emotional regulation.
Flexibility and problem solving in long-term goals.
That is, struggling to adapt to roadblocks.
Variable quality/quantity/speed of performance.
The 30% rule is sometimes used to understand patients with ADHD.
(Barkley, 2014)It suggests that ADHD individuals are 30% younger executively than they are biologically.
"Executively," meaning in their development of executive functions; this is not the same as cognitively.
ADHD symptoms may be related to atypicalities regarding neurotransmission of norepinephrine.
(Silver, 2022)ADHD brains may receive less reward or stimulation from activities.
This may be due to having fewer or less active neurotransmission receptors.
Or it may be due to hyperactive neurotransmitter reuptake resulting in neurotransmitters being removed from the system too fast.
When the ADHD brain doesn't receive enough reward or stimulation, it has to constantly seek out new sources.
This seeking may happen inwardly/mentally appearing as inattention, or outwardly/physically, appearing as hyperactivity/impulsivity.
SCT is a symptom cluster related to and common with ADHD, but separate from it.
There is controversy as to whether SCT should be considered a symptom cluster, a subtype of ADHD, or a separate attention disorder altogether.
When described as a separate disorder, the term "concentration deficit disorder (CDD)" is often used.
SCT is briefly mentioned in the ICD-11, but little elaboration is provided.
40-50% of individuals who experience SCT symptoms have ADHD, and 39% of individuals with ADHD experience SCT (Barkley, 2018).
Excessive daydreaming.
Trouble staying alert or awake in boring situations.
Easily confused.
Spacey of "in a fog"; mind seems to be elsewhere.
Stares a lot.
Lethargic, more tired than others.
Underactive or have less energy than others.
Slow moving or sluggish.
Doesn't seem to understand or process information as quickly or accurately as others.
Apathetic or withdrawn; less engaged in activities.
Gets lost in thought.
Slow to complete tasks.
These symptoms are very rare in the general population.
(Barkley, 2018)The presence of 3 or more of these traits puts an individual in the 93rd percentile.
An estimated 5% of children and adults in the US experience SCT (Barkley, 2018).
Symptoms can be categorized as either daydreamy-confused or sluggish/sleepy/lethargic (Barkley, 2018).
These two symptom categories correlate more with each other (0.75) than with ADHD-I (0.40-0.50) (Barkley, 2018).
This is a detail used in the argument that SCT should be considered a separate attention disorder.
What differentiates CDD from ADHD?
(Barkley, 2018).SCT symptoms do not diminish with age.
SCT is only slightly more common in males, and only in childhood.
SCT symptoms do not include impulsivity.
This is described as the most reliable differentiation between SCT and ADHD.
SCT and impulsivity may even be negatively correlated; SCT patients may be less likely to be impulsive than patients without either disorder.
SCT does not include executive functioning struggles.
Academic difficulties in SCT are more related to accuracy than productivity.
When ADHD children complete work they get 85% correct (vs. 94% in typical children).
SCT is associated with consistently slow reaction time.
Vs. ADHD which is characterized by extremely variable reaction time.
SCT has a very low or even negative correlation with behavioral disorders.
SCT is associated with social withdrawal or social reticence (being closed-off).
"ADHD children are rejected, SCT children are neglected, and typical children are accepted."
SCT is associated with social over-inhibition, where ADHD is associated with social disinhibition.
SCT is associated with anxiety and depression.
Coöccurrance of SCT with ADHD may account for the apparent correlation between ADHD and anxiety and depression.
SCT has no reliable link with intelligence or IQ.
64% of children with autism spectrum disorder have medium (33%) to high (31%) SCT symptoms.
SCT and ADHD combined creates worse impairment than either alone.
On their own, ADHD is much more impairing than SCT.
ADHD simulant medications are not helpful for SCT.
1/5 with SCT benefit from simulant medication, vs. 92% with ADHD.
Social skills training is beneficial with SCT students.
With ADHD students, social skills training is only temporarily beneficial.
The modern inclusion of CDD symptoms in the ADHD diagnostic criteria may account for ADHD's over-diagnosis trend.
(Barkley, 2018)If patients who qualify for CDD and not true ADHD under this model are removed from the sample, the rate of ADHD diagnosis has not increased.
Experienced by 70% of patients with ADHD (Gnanavel et al., 2019).
Experienced by 59% of patients with ADHD (Gnanavel et al., 2019).
Depression is experienced by 18-53.3% of patients with ADHD (Katzman et al., 2017).
This is more than five times higher than the rates non-ADHD youth experience (Gnanavel et al., 2019).
The association between ADHD and depression may be better explained by SCT.
Removing patients with SCT from samples eliminates the correlation (Barkley, 2018).
Experienced by up to 50% of patients with ADHD (Katzman et al., 2017).
Experienced by 40-50% of patients with ADHD (Brem et al., 2014).
Experienced by 30-50% of patients with ADHD (Gnanavel et al., 2019).
Experienced by 3.5-10% of patients with ADHD (Gnanavel et al., 2019).
ADHD is experienced by 55% of patients with Tourette's syndrome (TS) (Gnanavel et al., 2019).
Reality: ADHD brains seek out stimulation, so if an activity provides sustained stimulation then the individual can focus for a long time.
(World Health Organization, 2022)This is often referred to as hyperfocus.
Reality: Individuals with ADHD may present as hyperactive-impulsive, or they may present as inattentive (or as both).
(World Health Organization, 2022)Girls with ADHD often present as inattentive and may be overlooked at higher rate than boys because of this misconception.
Reality: ADHD is only slightly less common in girls (Barkley, 2006).
Reality: ADHD symptoms remain through adulthood in 50-70% of cases (Barkley, 2006).
International Classification of Diseases, Eleventh Revision (ICD-11), World Health Organization (WHO) 2019/2021 https://icd.who.int/browse11. Licensed under Creative Commons Attribution-NoDerivatives 3.0 IGO licence (CC BY-ND 3.0 IGO).
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Silver, L. (2022, April). ADHD Neuroscience 101. ADDitude Magazine. https://www.additudemag.com/adhd-neuroscience-101/
Barkley, R. A. & Adhd Videos. (2014, August). 30 essential ideas you should know about ADHD, 7B the 30% rule, 45 components for effective treatment. [Video]. YouTube. https://www.youtube.com/watch?v=4OVS16Abo80&list=PLzBixSjmbc8eFl6UX5_wWGP8i0mAs-cvY&index=15
Barkley, R. A. (2018, November 28). The second attention disorder - Sluggish cognitive tempo vs. ADHD. [Webinar]. University of Gothenburg. https://www.gu.se/en/gnc/birgit-olsson-lecture-2018
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Brem, S., Grünblatt, E., Drechsler, R., Riederer, P., & Walitza, S. (2014). The neurobiological link between OCD and ADHD. Attention deficit and hyperactivity disorders, 6(3), 175–202. https://doi.org/10.1007/s12402-014-0146-x
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