ADHD and Balance Impairment: Visual and Inner Ear Deficiencies

Balance dysfunctions and visual or vestibular deficiencies: Uncommon comorbids in the ADHD spectrum:

When we think of comorbid disorders to ADHD, we often envision disorders which can be diagnosed psychiatrically. Common examples such as depression, anxiety, Obsessive Compulsive Disorders (OCD), oppositional defiant disorders, and conduct disorders often come to mind. In addition, it is perhaps no surprise that learning disabilities are relatively common in children and adults with ADHD. If we do delve into physical comorbid disorders, things like Tourette's and tics may come to mind. For those skilled in the diagnosis and treatment of ADHD, even non-trivial comorbids such as bedwetting and sleep disorders may be apparent.

However, there is another impairment that often goes along with the ADHD population, especially in children. Sensory processing disorders are often seen in the ADHD population, especially in children. This includes more "physical" dysfunctions including the ability of the child to maintain balance and equilibrium. To the frustrated parent of coach of an ADHD child, this may introduce another complication with regards to sports or other activities which involve coordination and balance, such as basketball, baseball, tennis, soccer, gymnastics, musical instruments, dance, etc.

The aim of this post is to investigate and discuss impairments in balance function in children with the disorder, We will be citing and highlighting some key studies in the overlap between ADHD and balance dysfunctions (especially relating to functions derived from visual and tactile signals) and look for possible underlying causes and treatment methods:

Brain regions involved in Balance Dysfunction in the ADHD Child:

Most experts often cite specific "hot spot" regions of the brain for the ADHD patients. Among these, the prefrontal cortex part of the brain often receives the most attention. Less pronounced, however, are the studies associating the cerebellum, and their implications on ADHD. For a reference to the Prefrontal Cortex and Cerebellum brain regions, please consult the brain diagrams below:

Shown above is a human brain. The Cerebellum region, which plays a major role in governing balancing functions and may be compromised in a significant subsection of ADHD children, is shown in purple in the top picture. The area highlighted in orange in the bottom drawing roughly corresponds to the prefrontal cortex region of the brain, which plays a major role in impulse control. Deficiencies in blood flow and overall activity of this prefrontal cortex region of the brain are often seen in children (and adults) with ADHD, and may be responsible for some of the difficulties in filtering out comments and actions for appropriateness.

The inter-relationship between attention and balance/coordination: The strong association of the prefrontal cortex and cerebellum regions of the brain:

Many studies involving brain regions and ADHD often miss this connection. The relationship between these brain regions may go a long ways in explaining ADHD comorbid disorders as well, especially the more "physical" ones such as speech complications, developmental coordination disorders, etc. While perennial "hot spot" brain regions, such as the prefrontal cortex, are frequently mentioned in studies involving brain activity in ADHD, this particular brain region is actually intricately interconnected with the cerebellum (as well as another key brain region, the basal ganglia. The role of the basal ganglia in kids with ADHD has been discussed previously in other postings, but in general, the basal ganglia tell how fast a person "idles". 'Type A' personalities, such as workaholics, individuals with OCD and overly focused individuals typically have overactive basal ganglia, whereas many with ADHD often exhibit underactive basal ganglia.).

We have already mentioned that the balance-governing regions of the brain (the cerebellum) is interconnected with a key impulse-control region of the brain (the prefrontal cortex or PFC). We also mentioned that impulsivity is a characteristic of the Hyperactive-impulsive and Combined ADHD subtypes (as opposed to the more inattentive forms of the disorder). Interestingly, the prevalence of balance dysfunction cases seems to predominate in the combined subtype of ADHD (main paper as reference source). This correlation lends further credence to the hypothesis that the balance-governing and impulse-governing regions of the brain may be "co-affected" in the case of the balance-deficient, hyper-impulsive ADHD child.

Key points concerning balance related deficiencies and ADHD:

• ADHD is often associated with developmental delays. Indeed, studies highlighting a delay in cortical maturation in children with ADHD suggests that children and teens with the disorder may fall "behind the curve". By its own very nature, the vestibular system often does not fully develop until the age of 15, so immature development in this brain region may result in deficiencies in this system throughout almost the entire span of childhood in an individual with ADHD.


• Additionally, EEG and imaging studies have also demonstrated relative deficiencies in both size and activity (by measuring blood flow patterns) in various brain regions of ADHD children. These include the cerebellum and the caudate nucleus. Both are interconnected and associate with the "ADHD region" of the prefrontal cortex (PFC). This PFC region plays a major role in the impulse-control process and deficiencies in its function can result in a weak self-regulatory system of impulsive behaviors (which are hallmark characteristics of ADHD, especially in the hyperactive/impulsive and Combined subtypes).


• The cerebellum gathers input from visual, vestibular (inner ear), and somatosensory (mainly tactile senses, such as perceived through the skin and internal organs) systems. As we can imagine, a defect in one or more of these information-obtaining sensory systems, and the cerebellum (as well as the interconnected region of the PFC) may be compromised. Thus ADHD and sensory deficits may be intricately related.


• Taking this one step further, we may wish to explore the link between ADHD and sensory disorders, including processing disorders and sensory integration disorders. One thing is for sure, however: ADHD is not simply limited to deficits in the PFC!


• The vestibular system also plays a crucial role in what is known as "gaze stabilization" (i.e., stabilizing the focus on a particular fixed object when you yourself are moving). The very nature of "gazing" obviously has visual implications as well, so a deficiency in the vestibular component of gaze stabilization may also affect visual input success as well. Interestingly (an perhaps not surprisingly), visual input deficiencies are also seen at high rates in children with ADHD.
  
  This may actually serve as one of the key contributing factors as to why maintaining attention (to, say, a teacher), may be so difficult for ADHD kids, because they literally are having trouble focusing their visual attention (gaze) on their target of interest (i.e. a teacher standing up in class giving a lecture), especially if the child is already fidgeting around in their seat. In other words, there may be some inherent deficiency in this particular component of the attention span, and needs to be addressed further in the near future.

Investigating the sources of balance impairment in children with ADHD:
In order to clarify where I am coming from on this, I will highlight an extremely recent publication in the Journal of Pediatrics by Shum and Pang. This study investigated the different systems of balance in children, including somatosensory (balance governed by tactile features), visual, and vestibular (inner ear and the sense of equilibrium). They tested approximately 50 children (ages 6-12) with ADHD for balance discrepancies by isolating each of the three systems listed above to test sensory organizations of balance. A highlight of the study can be seen below:

Instruments/Methods of the study:

1. A platform which can induce a feeling of motion on a child who stands upon it (this disrupts the somatosensory component of balance, forcing the child to use their visual or vestibular functions to compensate for the somatosensory impairment).
2. Surrounding scenery which can visually give the illusion of motion. This forces the child to use their vestibular and somatosensory methods of equilibrium, as the visual sense is disrupted. Another variation of this is to have the child perform with their eyes closed.
3. A combination of the two methods above will isolate the vestibular component of balance, as both the somatosensory and visual sources of balance are now both compromised.
4. A total of six different environmental conditions were performed to isolate one or more senses of balance. The researchers noted which of the three modes of balance were most likely to be compromised in the ADHD children. The findings are highlighted below:
   

While balance-related issues can stem from visual discrepancies, somatosensory issues (i.e. the sensations of touch and pressure from the skin and even internal organs), and vestibular (inner ear) imbalances, it appears that ADHD children are most likely to suffer from visual imbalances. This is closely followed, however, by deficits in vestibular function. Somatosensory difficulties appear to occur in ADHD children as well, but the role of this system is likely to be much smaller than for the other 2.

Possible academic implications of balance dysfunction and ADHD: Does the source of an ADHD child's balance deficiency affect his or her sensory learning style? The following points are simply the result of this blogger thinking out loud. Nevertheless, these might be some good topics of future study, as balance difficulties may be useful in evaluating academic strategies.

• These findings on balance may even extend to the classroom and affect the learning environment of an ADHD child. Given the above, abnormalities in these areas may even affect a child's mode of learning and learning style. While these assertions simply remain personal hypotheses of this blogger, a child with visual discrepancies leading to balancing difficulties may also be deficient in visual perception and therefore struggle in a visual-dominated learning environment. He or she may gravitate towards a more auditory or kinesthetic style of learning.
  

• Conversely, it is also possible that vestibular-regulated balance dysfunctions, which stem from the inner ear may actually extend to a child's auditory learning capabilities. Again, this remains a hypothesis, but given the fact that severe childhood ear infections can affect both balance and hearing (as well as ADHD symptoms, see previous post on childhood ear infections and ADHD), a child with vestibular-related balance deficiencies may also have more difficulty in a predominantly auditory-based learning environment. This may spell bad news if an ADHD child's teacher engages in more auditory discussions or as the child moves up to high school and college courses where an auditory lecture is the more common form of teaching and communication.
  

• A double-whammy?: Given the fact that children with ADHD may suffer from both vestibular and visual (and even somatosensory) information processing for balance, it leads us to wonder if the child may also have learning deficits in 2 of the 3 major forms of learning (visual, auditory or kinesthetic). If this is the case, trying to accommodate an ADHD child's education could be extremely difficult, if he or she must heavily rely on only one predominant mode of acquiring and processing information.
  
  For example, if a child were to undergo a study similar to the one listed above, and it turns out that he or she is weak in both the visual and vestibular forms of balance, and (this is a big "if" and is only hypothetical at the moment) the whole balance governing/learning style hypothesis holds true, he or she may have to rely on a predominantly kinesthetic form of learning. While this child may succeed in hands-on learning subjects (i.e. frog dissection or wood shop class), he or she may have an exceedingly difficult time in other subjects such as algebra or history where hands-on-learning opportunities are more difficult to implement.
  
  

• The role of balance and sensory stimulation may have even greater-reaching academic implications. Another study just came out recently investigating the role of posture stability (i.e. how well a person stabilizes their center of balance) on ADHD and dyslexia. The study found that comorbid ADHD symptoms greatly influenced the effects of posture stability in dyslexic individuals, which may even have implications to affecting the reading environment of the individuals with dyslexia. It's important to keep in mind that this study involved adults instead of children, but the fact that ADHD may play such an integrated role into sensory modulation of other disorders into adulthood may signify the deep level of inter-relationship between cognitive function and sensory motor stimulation.
  

Vestibular Stimulation as an alternative form of ADHD Treatment?: As an interesting aside, there has been some pronounced effect on treating ADHD symptoms with a non-pharmaceutical alternative method called vestibular stimulation. We will be addressing the validity of these findings and their potential for practical usage in a later discussion.

Childhood Ear Infections and ADHD: Why the link?

When we scan the literature for statistics on ADHD and search for early warning signs or tip-offs that a young child may be prone to the disorder, a few common trends seem to pop up again and again. One of these is the high rates of ADHD and attentional difficulties in kids suffering infection of the middle ear (Otitis Media) in early childhood.

During early childhood, the actual positioning of the ear canal is still adjusting, the pathway into the middle part of the ear is actually at a flatter angle than in a mature adult. This difference in positioning actually makes younger children much more prone to ear infections than older children or adults. Unfortunately, these infections may increase the risk of further complications down the road, including an increased onset of attentional difficulties, including ADHD. Here is what some of the literature has to say about the ADHD/ear infection connections:

Relationship between middle ear infections and inattention: The basis for inattentive ADHD?

The main culprit for attentional deficits is often believed to be the result of hearing loss (even mild), early in a child's life due to complications with the middle ear, including infections, allergy-related causes or build-up of fluids in the canal. As a result, the child begins to miss out on verbal cues, and does not develop the same level of response to an adult voice. Auditory deficiencies (including auditory processing disorders) may stem from this key development period, even if the hearing difficulties are only temporary.

Not surprisingly, there is a wealth of data associated with hearing loss due to middle ear complications can lead to language processing difficulties. We have seen how auditory processing disorders can often occur as a comorbid factor in ADHD, and may be linked to seemingly unrelated behaviors including comorbid anxiety and conduct-related disorders.

It is important to note, however, that other early childhood studies have not seen a link between infection and attentional difficulties (observed by parents, teachers, or clinicians).

Interestingly, environment may play a huge role in explaining this discrepancy between study results. One study found that children who had middle ear complications early on along with poor home environments were significantly more likely to develop attentional difficulties (along the lines of what would be classified as ADHD). Therefore, the effects of early ear infections on compromised attentional difficulties may be significantly reduced if a supportive home environment is maintained for a child. This is good news for parents of children with ear infections. But what about the hyperactive component of ADHD?

The link between hyperactive behaviors and middle ear complications: The basis for hyperactive/impulsive or combined subtype ADHD?

While it seems more intuitive that ear infections could lead to auditory problems and subsequent attentional difficulties (especially to auditory cues), the relationship between ear infections and hyperactivity is less inherently obvious. This association would be more relevant to the hyperactive/impulsive and combined subtypes of ADHD.

For over 30 years, researchers have linked high rates of ear infections and hyperactivity (this study used the term "minimal brain dysfunction", a phrase which this blogger has personal objections, nevertheless, it is a relatively common term in the literature). Later studies confirmed these findings, including one which reported the majority of children medicated for hyperactivity had a past history of 10 or more childhood ear infections. These numbers were in sharp contrast to the prevalence of ADHD in non-hyperactive children.

One thought may be that ADHD which includes a significant hyperactive component (as opposed to the more inattention-dominated form of the disorder) is more likely to be associated with comorbid disorders that correspond to ear infections. We have seen previously that comorbid disorders to ADHD are often related to particular subtypes.

For example, anxiety and depressive-like symptoms are often more likely to co-exist with primarily inattentive ADHD, while conduct disorders are more likely to co-exist if there is a high hyperactive/impulsive behavior (especially in the combined subtype). In general, the prevalence of more severe learning disabilities is often more associated with the inattention-dominant form of ADHD, while motor tics are more likely to be a hyperactive/impulsive trait. Carrying these associations in mind, are the studies linking early ear infections to hyperactivity simply due to associations with hyperactive subtype-dominated comorbid disorders?

One particular study found that children with hyperactivity vs. children with learning disabilities (and not hyperactivity, remember, learning disabilities are often seen at higher rates in the inattentive forms of the disorder) had similar numbers of total childhood ear infections. However, the timing of the infections did seem to matter. Children with hyperactivity experienced more recent ear infections (within the previous year) compared to the learning disability kids.

In other words, the question surrounding hyperactivity and ear infections may be more of a "when" question than a "how many" question. This may also suggest the possibility that hyperactivity due to middle ear troubles may be more of a temporary condition (this is supported by trends as an individual with ADHD ages, typically, the hyperactive symptoms of the disorder begin to subside as a child gets older and reaches adulthood, while the inattentive symptoms are more likely to plateau) as opposed to inattentive problems stemming from ear infections. Severity of the infections may also be a triggering cause or associated warning sign of an increased risk of developing hyperactive behaviors. The same study found that earaches and upper respiratory tract infections were higher in the hyperactive group than in the less-hyper learning disability group.

So what's going on with the connection between ear infections and ADHD-like hyperactivity?:
Although none of the above studies mentioned this possibility, as a blogger I have a few ideas on the subject. One of the most probable reasons for the ear infection/hyperactivity correlation may be due to the treatment process of ear infections. Let me explain:

Ear infections are typically treated with antibiotics. While these drugs work wonders for most infections, they also can disrupt the healthy bacterial counts in the digestive tract (that is, they kill off many of the "good" bacteria in our digestive systems in addition to the "bad" bacteria which may be causing our infections).

If the "good" digestive bacterial counts fall too low, the digestive process is compromised. The absorption and digestion process may suffer, as key nutrients may now be compromised (even if no major dietary changes occur). We have spoken extensively about nutrient deficiencies and ADHD as well as ADHD-related nutrition strategies in earlier posts.

Additionally, if good bacterial counts fall low, incomplete digestion results, which can lead to byproducts such as higher concentrations of organic acids, as well as incomplete breakdowns of potential allergens (which can increase sensitivity to food allergens, among others). These allergens and acids can actually begin to penetrate the blood brain barrier and show up in higher concentrations in the brain. Neurological disorders, including abnormal hyperactivity may actually be triggered by digestive imbalances (to a degree beyond what most of us realize). We are just beginning to recognize the huge degree of inter-relationship between the nervous and digestive systems, including brain-gut interactions.

There has been a longstanding "hot" discussion surrounding food allergies and ADHD (as well as possible connections between food allergies and disorders like fibromyalgia and chronic fatigue syndrome), and the disrupted bacterial balance in the digestive system due to frequent antibiotic usage for recurrent ear infections may be a governing factor. This seems to make sense, especially considering the fact that hyperactivity was more linked to recent ear infections (and resultant antibiotic treatment), while the more inattentive behaviors and learning disorders seem to be a more long-standing symptom. Since bacterial counts begin to re-stabilize following antibiotic treatment (if a proper diet is maintained), the food-related hyperactivity may begin to subside, but for recent infections and treatments, the digestive bacteria may still be imbalanced, triggering an onset of ADHD-like hyperactive behaviors.

Of course this is just the blogger's personal hypothesis, but it at least seems plausible that the actual treatment for ear infections may play an equally strong role on the high rate of occurrence between ADHD and ear infections.

Ginkgo biloba for ADHD: A natural herbal treatment alternative?

A few weeks ago, I discussed the merits of ginseng for treating ADHD. What I did not mention is the fact that this special herb often works even better in tandem with another important "brain herb", Ginkgo biloba. It's benefits also extend beyond the nervous system, and the Ginkgo has been used to treat everything from increasing blood flow to Alzheimer's to glaucoma to hormone replacement to protection against neuronal degradation. While somewhat wary (personally) of using generalized "brain booster" nutrients for ADHD (it is a highly variable disorder of complex etiology and treatment methods), I am interested whenever new research publications arise on the topic. Just this week, a new paper came out on the merits of Ginkgo biloba as an ADHD treatment option.

Here are some of the major points of the publication:

• Irritability is an often overlooked side effect of ADHD. Medications, especially over-prescription with stimulants such as methylphenidate and amphetamines can increase this unwanted side effect. However, Ginkgo exhibited a positive mollifying effect on irritability for the individuals in the study.
  
  
• While one of the knocks against Ginkgo biloba is that it can sometimes result in sedative effects, the study found these to be extremely mild. However, to go along with the irritability-reducing benefits above, Ginkgo was able to improve the individuals' tolerance for frustration (to the degree that this behavior could be measured).
  
  
• We have seen previously that oppositional defiant behaviors are often comorbid to ADHD (which can often manifest themselves alongside seemingly unrelated disorders such as auditory processing disorders or even bedwetting). One of the strongest suits of Ginkgo biloba may actually be in curbing these oppositional behaviors. This suggests that Ginkgo may be effective for the more Hyperactive/Impulsive or Combined Subtypes of ADHD, where comorbid oppositional behaviors are more often seen (as opposed to the predominantly inattentive subtype of the Disorder).
  
  
• Nevertheless, Ginkgo biloba appeared to boost symptoms of attention and working memory as well. This may suggest Ginkgo's versatility, and that it could be used universally across the ADHD "spectrum", including for the 3 classic or traditional subtypes of the disorder.
  
  
• The study highlights the relative success for co-treatment with methylphenidate and clonidine for individuals with ADHD and comorbid anxiety disorders. The authors suggest a functional comparison between Ginkgo and clonidine, and hint at its use as an alternative to clonidine/methylphenidate treatment (of course, it is also possible that Ginkgo may be used alongside lower doses of stimulant medications, which could be very useful in reducing unwanted side effects, which are often mild for low doses of stimulants, but typically begin to appear with greater frequency when stimulant dosing is increased). Thus, Ginkgo could possibly act as a side-effect-saving alternative to higher doses of medication.
  
  
• As a precautionary measure, due, in part to some of its anti-clotting properties, there is some concern about Ginkgo triggering internal cerebral bleeding. Indeed, other studies have also addressed this possible concern, highlighting issues such as haemmorrhage risks, as well as herb-drug interactions with Ginkgo and anti-coagulant medications.
  
  
• Keep in mind the extremely small nature of the study (only 6 individuals) should be met with healthy skepticism. However, the results were still notable. Statistically significant reductions in some of the trademark ADHD symptoms (fidgeting, restlessness, inattention, etc.) upon Ginkgo biloba treatment definitely highlight its potential as a more "natural" alternative treatment method for ADHD.
  

Why the Menstrual Cycle may affect ADHD Medication Dosing Levels

Do hormonal fluctuations result in variable ADHD medication dosage levels across the menstrual cycle?

We have investigated the impact of gender on ADHD in a number of earlier posts. We have covered topics such as:

• Gender Based Metabolic Differences in ADHD brains

• Gender Dependent ADHD Genes, including MAOA, SLC6A2, SLC6A4 and COMT

• ADHD subtypes and Comorbid Disorders

Clearly, there are a number of boy/girl differences in the root causes, diagnoses and treatment methods for the disorder.

However, we need to investigate whether intra-individual differences are also an important factor, especially where medication treatment and medication dosing levels are concerned. Based on a number of studies, it appears that women may actually require different medication dosing levels depending on where they are in their menstrual cycle. Additionally, post-menopausal drugs such as estradiol patches may also alter the drug effects of certain ADHD medications such as amphetamines. The main culprits are most likely fluctuating levels of estrogen and progesterone.

Here are brief summaries on some of the relevant studies and their findings. Wherever possible, I will include a link to the original studies:

• The link between Estradiol treatment and amphetamine medications: This study focused on whether pretreatment with estradiol played any role in the reaction to amphetamines. The drug used in this study was D-Amphetamine, which would correspond to the medication Dexedrine, however, this is also the predominantly active compound in medications such as Adderall or Vyvanse (once this "pro-drug" is metabolized). It is unclear at the moment whether chemical "cousins" to amphetamines, such as methylphenidate (Ritalin, Concerta, Daytrana, Metadate), also exhibit these fluctuations when combined with estradiol-releasing drugs.
  
  The study found that for females who took estradiol-supplementing treatments during the early follicular phase (pre-ovulation) of the menstrual cycle experienced an overall greater "stimulating" effect of the amphetamine medication (taken as 10 mg of amphetamine). This may suggest that a slightly lower dosage during this stage of the menstrual cycle might be warranted, and (as this blogger's personal hypothesis) may actually affect the addiction potential of ADHD stimulant drugs such as amphetamines.
  
  
• Another study by the same group found that estrogen may be responsible for some of the heightened euphoric effect felt from amphetamine-based drugs. However, the hormone progesterone may actually counteract some of this euphoria. During the luteal phase of the menstrual cycle (after ovulation), high levels of both estrogen and progesterone are seen (although levels of both of these taper off going into menstruation), so the effects of estrogen may be curbed. During the late follicular phase, where progesterone levels are low and estrogen levels begin to spike, the "high" may be at its peak, especially if stimulants are involved.
  
  
• A case study found that an increase in inattentive symptoms coincided cyclically with the menstrual cycle for a patient who was undergoing treatment for newly-diagnosed ADHD with a twice-daily dosing regimen of the stimulant medication Concerta.
  
  
• The findings from these two studies suggest the possibility that a slightly smaller dosing schedule with amphetamine-based ADHD medications (such as Adderall, Vyvanse or Dexedrine) may be warranted during the follicular phase. However, during the luteal phase, when progesterone levels are higher, the amphetamine-based effects are less pronounced. This may correlate to a slightly higher dosing regimen for amphetamine-based treatment for ADHD and related disorders.
  
  
• While there is a relatively good theoretical basis for this assertion above, practical consideration measures must also be considered. Based on the relative scarcity of studies (besides the 2 mentioned above) on the amphetamine-menstrual cycle interactions, it is unclear as to how pronounced the medication change should be.
  
  For instance, should someone taking 10 mg of Adderall during the follicular phase boost up to 15 mg for the luteal phase? 20 mg? 30 mg? Additionally, hormonal fluctuations vary during the phases themselves, such as the estrogen spike during the late follicular phase. Questions abound, especially when dealing with the brief ovulatory phase as well.
  
  

This blog post hopefully introduces what may be a new consideration to women who have ADHD and are currently taking stimulant-based medication treatments. Perhaps this posting simply confirms what you have already experienced.

Nevertheless, given the fact that administering variable levels of medication based on cyclical patterns such as time of day (like ramping up methylphenidate concentrations via controlled release formulations to offset "acute tolerance" based effects), and the fact that individuals with ADHD may experience seasonal variations in symptoms, at least suggests, that variable dosing of medications across the near-monthly period of the menstrual cycle may prove to be beneficial treatment strategy for females with ADHD.

Long Wave Infrared Imaging: A new detection method for ADHD?

Detecting ADHD using the long-wave infrared spectrum:

I always enjoy covering new breakthroughs in the diagnosis and treatment methods in the medical field. A new study just came out which may have a number of potential applications to aid in the diagnostic process of ADHD, which I believe is worth sharing. Called Long-Wave Infrared Imaging, this method utilizes the infrared spectrum to detect biological activity (namely bloodflow patterns) via the differences in radiation emitted by these activities. The study, titled Sensitivity and Specificity of Longwave Infrared Imaging for Attention-Deficit/Hyperactivity Disorder, found that this method may be a surprisingly powerful way of separating ADHD from other related disorders, aiding in the always-difficult process of differential diagnosis.

The basics of Long-Wave Infrared Imaging:

The term "long-wave" is a relative term, of course, referring to wavelengths of approximately 10 nanometers (or only one one-hundred millionth of a meter). Differential bloodflow patterns can result in temperature differences by a full degree (Celsius), making this technology useful in tracking bloodflow disorders. A recent publication in the Journal of Medical Physics by Bagathaviappan and coworkers suggests describes how this long-wave infrared imaging can detect areas in the circulatory system where bloodflow activity is sluggish or reduced. Typically, these areas appear "cooler" on the spectrum, due to the lack of a new, replenishing blood supply.

Applications for ADHD:

A number of studies have confirmed the hypothesis that individuals with ADHD have reduced bloodflow levels marking a recuction of activity to multiple key brain regions. Additionally, while several disorders have a number of overlapping symptoms (which can make the diagnostic process more complicated, especially if multiple comorbid disorders are present), differential blood flow patterns to the brain may be able to help make these distinctions. For example, blood flow patters to the brains of ADHD and OCD (Obsessive Compulsive Disorders) can show pronounced differences, which can aid the diagnostic process between these two disorders (while ADHD and OCD are often considered to be on "opposite" ends of the spectrum with regards to neuro-chemical signaling levels, these two disorders can often exhibit similar symptoms, such as a severe impairment in the response to verbal directions. This is especially true in younger children).

This technology may even be extended to measuring or predicting which medications may work for an individual diagnosed with ADHD, based on blood flow in specific localized brain regions. Cerebral blood flow patterns may help predict the response to common ADHD drugs such as methylphenidate (Ritalin, Concerta, Metadate, Daytrana). For example, a study by Cho and coworkers found increased blood flow in at least three different brain regions for individuals who showed poor response to methylphenidate treatment compared to their peers who did show improvements under the drug.

While the medication response study was done utilizing a different type of brain imaging device known as SPECT, which utilizes gamma rays and radioactive tracers to detect brain activity in 3-dimensional patterns. While SPECT has proven to be an extremely powerful and effectively safe method of detection (the radioactive isotope used in this method is relatively non-invasive and breaks down quickly, and the gamma rays are carefully controlled), concerned parents may still have an inherent fear of the terms "radioactivity" and "gamma rays" tend to shy away from this powerful detection method on their kids.

While this blogger personally has a very high opinion about the use of SPECT as a diagnostic tool for ADHD and related disorders, it is at least worth mentioning the possibility that long-wave infrared imaging methods may be a viable alternative method in at least some of these imaging cases (SPECT technology has been around for over 30 years, but the recent advances in computational power resurrected this technology in the very recent past, similar possibilities may abound by this infrared technology, which has been around even longer).

Keep in mind that the studies utilizing this range of infrared imaging technologies for detecting and differentiation disorders such as ADHD are still relatively scarce. Nevertheless, long-wave infrared imaging appears (at least in this blogger's personal opinion) to be a powerful diagnostic tool for ADHD and related disorders in the near future.