1. Motor symptoms of ADHD

• 1.1. Hyperactivity
  • 1.1.1. Motor hyperactivity as an ADHD symptom
  • 1.1.2. Manifestations of motor hyperactivity
  • 1.1.3. Age-related decrease in motor hyperactivity
  • 1.1.4. Hyperactivity as a symptom of stress
• 1.2. Gross motor problems in ADHD
• 1.3. Fine motor problems in ADHD

1.1. Hyperactivity¶

Motor hyperactivity is a very common symptom of ADHD. However, hyperactivity is not a mandatory symptom of ADHD. There are ADHD sufferers who suffer a lot from their symptoms, who were / are neither hypermotor as a child nor full of inner restlessness as an adult.

1.1.1. Motor hyperactivity as an ADHD symptom¶

Motor hyperactivity is a characteristic of ADHD-HI and ADHD-C. In the ADHD-I subtype (predominant attention problems), hyperactivity is less pronounced.¹
Hyperactivity often subsides in adolescence. The literature describes that hyperactivity in adults usually turns into a form of constant inner restlessness. This will have to be discussed.

Fidgeting and constant moving could be understood as an internal correction of vigilance (basic internal tension) and too low dopamine level. Movement increases dopamine levels.²³ Fidgeters who are forced to sit still are (still) more likely to give wrong answers than when they are allowed to move.² Likewise, exercise before school (to work out motor restlessness) increases learning success.²

1.1.2. Manifestations of motor hyperactivity¶

• for young children:
  • Extended child defiance phase
  • If necessary with excessive veritable tantrums
• for children:
  • Constant fidgeting with hands and feet or sliding around on the chair (DSM IV/5)
  • Frequently stands out in class and other situations where sitting is expected (DSM IV/5)
  • Frequently runs around or climbs excessively in situations where this is inappropriate (in adolescents or adults, this may be limited to a subjective feeling of restlessness) (DSM IV/5)
  • Often has difficulty playing quietly or engaging in leisure activities quietly (DSM IV/5)
  • Is often “on the move” or often acts as if he/she is “driven” (DSM IV/5)
  • Often talks excessively (DSM IV/5; rated as an impulsivity trait in ICD-10). Speech diarrhea is still seen in some adults as well
• for adults:
  • Hyperactivity (external/physical) decreases up to 60% in adults⁴
  • Physical restlessness in adults possibly only to a lesser extent
    • Foot bobbing with high frequency (in each case even if deliberately suppressed)⁵
    • Finger drumming (even if deliberately suppressed)⁵
    • Nail biting⁶
    • Lips bite
    • Tie legs in knots / wrap around chair leg to limit movement⁶

1.1.3. Age-related decrease in motor hyperactivity¶

ADxS.org symptom test data show the following changes in age groups:

Age group	motor hyperactivity	inner restlessness	attention problems
5- 9 years (n = 9)	0.70	0.80	0.75
10 - 14 years (n = 15)	0.72	0.68	0.83
15 - 19 years (n = 48)	0.45	0.62	0.81
20 - 29 years (n = 373)	0.49	0.70	0.81
30 - 39 years (n = 492)	0.49	0.74	0.83
40 - 49 years (n = 301)	0.46	0.74	0.78
50 - 59 years (n = 158)	0.46	0.72	0.80
60 - 75 years (n = 32)	0.42	0.74	0.72
Men (n = 630)	0.52	0.73	0.81
Women (n = 823)	0.45	0.72	0.80

As of June 2020. The values given reflect the severity of the symptoms relative to each other.
Limitations of the informative value:

• There are few data sets with subjects under 20 years of age and significantly too few data sets with subjects under 10 years of age for a robust conclusion.
• No separation was made between ADHD-I and ADHD-HI, so the (random) ratio of ADHD-I to ADHD-HI may bias the data for small group sizes.
• Only those records were evaluated in which the symptom test found evidence of an existing ADHD.
• It is a non-validated online self-test (screening).

The data are in agreement with the thesis that attention problems are not yet fully developed in children up to 15 years of age and that motor hyperactivity decreases in adulthood. However, they suggest that hyperactivity does not change into inner restlessness, but that inner restlessness also exists in children and merely regresses less than hyperactivity. After the regression of motor hyperactivity, inner restlessness only seems to become more visible.

The inner restlessness, the constant circling of thoughts (rumination), could be called the “little brother” of hyperactivity.

1.1.4. Hyperactivity as a symptom of stress¶

Hyperactivity, fidgetiness is known as a typical symptom in severe stress, as well as that during stress the thoughts are concentrated on the stressor (thought circling, rumination).
Symptoms of stress are:

• Unrest⁸⁹
  Inner restlessness is a typical symptom of the approaching end state of burnout.¹⁰
• Restlessness¹¹¹²
• Movement restlessness¹³

The stress hormone CRH, which is released in the first stage of the HPA axis by the hypothalamus, directly mediates an urge to move. Increased locomotor activity is a direct effect of the stress hormone CRH.^141516139

Symptoms that are directly mediated by stress hormones themselves may nevertheless also be ADHD-specific symptoms. Chronic stress like ADHD mediate their symptoms through dopamine and norepinephrine deficiency in the brain.

1.2. Gross motor problems in ADHD¶

Gross motor and fine motor disorders should be considered separately from motor hyperactivity.

Appearances:

• Clumsiness
  • Frequent bumping/hanging
• Many accidents (clumsiness meets hectic pace)
  • Frequent injuries (esp. ADHD-HI)
  • Bruises
• Coordination problems (dyscoordination)
  • E.g. learning to ride a bike only at 6 years old
  • E.g. difficulty keeping balance or standing on one leg¹⁷
• Difficulties of force dosage

Preliminary data from the ADxS.org online symptom test (as of October 2018) suggest that gross motor problems are far more common in ADHD-HI with hyperactivity than in the ADHD-I subtype. Research supports the association between gross motor problems and hyperactivity/impulsivity.¹⁸

1.3. Fine motor problems in ADHD¶

Gross motor and fine motor disorders should be considered separately from motor hyperactivity.

Appearances:

• Spidery handwriting¹⁹
  • Disproportionate increase in dictation under time pressure²⁰
• Children find it difficult to color pictures neatly²⁰
• Precision mechanics are difficult (e.g., smooth cuts with scissors, insert small screws)

Fine motor problems are about equally common in ADHD-HI as in ADHD-I.¹⁹

Interestingly, although fine motor problems seem to be quite common in ADHD, rather few sufferers report to us that handwriting has improved under ADHD medication.