At ADDspeaker we have our own term: ADHtism, which refers to those of us who have both ADHD and ASD, 20-50% of all cases meets this description. Here we look at some of the science behind our hypothesis.
What ADDspeaker says …
Many of those of us who suffer from both ADHD and ASD have long had the notion that when our ADHD is medicinally treated, our autistic traits become more obvious and create whole new challenges for us.
ADHD is a specific neurodevelopmental disorder, ASD is a pervasive neurodevelopmental disorder. This means that ASD is more wide-ranging in its symptomalogy than ADHD which is mostly related to higher brain functions in the prefrontal cortex (PFC), such as Executive Functions and Inhibition, whereas ASD is more related to sensory systems and basic brain functions within the Limbic System.
Since ADHD symptoms are more motor system related (verbal and non-verbal) than ASD (perceptions, sensations and emotions), it makes perfect sense that when the ADHD is treated with medication, the symptoms of ASD become more obvious.
ADHD and ASD relates to many neuronal systems in the brain and these operate using electrical and/or chemical signals, called neurotransmitters.
As you can see these are either excitatory or inhibitory.
Excitatory means that they will try to create an action in the brain, whereas Inhibitory will try to inhibit the creation of an action in the brain.
These neurotransmitters are crucial for controlling verbal (speech) and non-verbal (physical) behaviours which is what causes the relentless talking, excessive body movement, emotional dysregulation (anger, frustration) and mind wandering (aloofness, hyperfocus) etc.
As many of you maybe know, Dopamine is one of the key neurotransmitters related to the deficits in inhibition of motor control (verbal and non-verbal), which is at the core of all ADHD symptomatology, since ADHD is basically causing a 30% delay in normative brain development, compared to children at the same age and intellect.
This delay is due to the fact that the Motor Control Systems in the brain develops before the Inhibitory Systems in the brain, causing an out-of-control verbal and non-verbal motor systems. (Barkley, 1997)
ADHD causes a 30% delay in maturation in the brain, which causes the motor control systems to develop before the inhibitory control systems, and that is why ADHD causes massive deficits in behavior, our motor control is running amok, unrestricted from inhibitory control …ADDspeaker
There are many different types of these, but those we have found to be most relevant are:
- Dopamine (excitatory)
- Epinephrine (excitatory)
- Norepinephrine (excitatory)
- Serotonin (excitatory)
- GABA (inhibitory)
The overlooked missing link?
It is well known that Dopamine is crucial for all reward related actions, and that Serotonin is what controls our mood, but what is less known (in relation to ADHD) is that GABA plays a significant role in inhibiting behaviour as well.
I am following an online course in Medical Neuroscience (you know, just for the fun of it …) and in that course it was explained that GABA actually is excitatory in prenatal human brains, and that they become inhibitory postnatal. This sparked my interest immensely since this could explain why ADHD medication is not able to reduce all symptoms, only those related to Dopamine primarily, since our postnatal brain is 30% delayed and so GABA may invariably also be delayed, right?
So I thought, hmm … what if the prenatal immature GABA is still present in the postnatal ADHD brain (due to the neurodevelopmental delay) and what if GABA is adding fuel to the fire by not acting inhibitory, but excitatory?
I took my hypothesis to Dr. Russell A. Barkley, PhD, who have become my (unofficial) mentor (poor guy never volunteered, I might ad) and since he is an openminded, welcoming scientist with 40+ years of experience in ADHD (he literally wrote the book on ADHD back in 1997), he took time to answer me back and confirmed my hypothesis as plausible (note not factual!) in relation with GABA having a role to play in ADHD as well.
Hi Peter, Yes, GABA could be one influence on ADHD brain related problems and so medications that alter GABA might be useful. I would be more hesitate about all those drug combinations without more research on their possible interactions. But the basic thesis has merit, as Amy Arnsten, MD discussed in her presentation last weekend at our APSARD meeting. Be well, RussDr. Russell A. Barkley, PhD, Jan 22nd, 2019
That made me feel like the most brilliant guy in the world, right? and to add fuel to my ever growing Megalomanic Personality Disorder (joke, you autist, joke), I began to take myself serious and formulated this hypothesis …
Possible medical treatment for ADHtism?
ASD does not have any (official) medication for treatment, but our experience with combining Guanfacine (non-stimulant) with Methylphenidate or Dexamphetamine (stimulants), seems to work very well in unison, as the non-stimulant addresses the sensory and emotional symptoms (Limbic System), whereas the stimulants addresses the hyperactive, impulsive and inattentive symptoms (Executive Functions, PFC).
If you administer stimulants alone, to a person with ADHtism, you may only treat the visible symptoms and the ASD symptoms becomes very visible, especially you will experience heightened level of autistic hyperfocus, having lot more difficulty changing tasks and become even more (disassociated) impaired in social relations.
If you administer the Guanfacine first and the stimulants afterward, you may experience that the internal chronic stress of sensory overload from ASD will be significantly lowered, while the hyperactive, impulsive and inattentive symptoms will be treated with more efficacy, than seen with combining them.
The most surprising fact is that the impairments in emotional self-regulation and emotional self-control, called Emotional Dysregulation, which is primarily known from ADHD but which is also a (hidden) deficit in ASD, actually gets treated very well, when combining these drugs for those of us with the ADHD and ASD combo, aka ADHtism.
It makes sense, since sensory deficits leads to stress which leads to frustration which leads to aggression which cannot be self-soothed and self-regulated due to the ASD, and which becomes even more expressed in behaviour due to the ADHD.
When you lower the stress then you lower the rest of the ‘chain’ of events and since stimulants increase your ability to ‘stop, think and then act’, then I believe that we may have some credence in our hypothesis.
If you add the fact that GABA might be off balance as well in the ADHtistic brain, then one could argue administering Gabapentin as well, as that drug will increase the inhibitory function of the GABA system, and maybe it can help mediate some of the lack of inhibitory control, at the low level in the Limbic System and act in unison with Guanfacine and Methylphenidate/Dextroamphetamine could build on that to improve Executive Functions in the PFC.
But as Dr. Barkley cautioned me; be careful that critics don’t accuse you of practicing medicine without a license if you publicize this stuff in that you are making drug recommendations. The topic is fine to discuss.
So to make it abundantly clear, I AM NOT A LICENSED DOCTOR AND I DO NOT PRACTICE MEDICINE. THESE ARE NOT RECOMMENDATIONS, THESE ARE THOUGHTS AND ASSUMPTIONS THAT NEEDS TO BE VALIDATED BY SCIENCE, NOT ME!
That said … I feel lucky …
What the Science says …
The experiences that I have from real life (from our personal and community experiences) illustrate that the hypothesis of ADHtism may not be so far fetch, and this new study from Amori Mikami shows that the overlap in symptomalogy is something that is distinct, opening the door for future studies into this area.
There has been growing recognition of the frequent co-occurrence, and potential interrelatedness, between ADHD and ASD without intellectual disability. In fact, the most recent (5th) edition of the DSM is the first to allow ADHD and ASD to be diagnosed in the same individual (Mikami et al., 2019).
The study of transdiagnostic features in ADHD and ASD is important for understanding, and treating, these commonly co-occurring disorders. Social impairment is central to the description and prognosis of both disorders, and many youth with some combination of ADHD and ASD present to clinics for social skills training interventions (Mikami et al., 2019).
These findings have implications for interventions to address social problems in youth with these conditions. We conclude with a discussion about areas for future research and novel intervention targets in youth with ADHD, ASD, and their comorbidity (Mikami et al., 2019).
However, the aspects of social functioning that are impaired may have both shared and distinct features between the two disorders, relating to some overlapping and some diverse etiologies of social problems in ADHD compared to ASD.Mikami et al., 2019
Dr. Amori Mikami is a Professor in the Department of Psychology at the University of British Columbia. She is also a registered clinical psychologist in British Columbia, Canada.
- Association for Psychological Science Rising Star (2011)
- Canadian Psychological Association Rising Star (2011)
- International Social Cognition Network (ISCON) Award (2005)
- American Psychological Association Award (2005)
Mikami is known as one of the foremost researcher on peer-relatedness related to ADHD and her work is widely accepted as the Gold Standard for psychosocial treatment for children with ADHD. Dr. Barkley have talked highly about her work as well. For a full list of Mikami’s publications, visit the lab website.