Stims include humming, tapping, or nail biting unconsciously. If your ADHD stimming soothes you, great! If it distracts or embarrasses you, there are ways to manage it.

Person with adhd humming and cracking her knuckles as stims to soothe and focusShare on Pinterest
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Self-stimulation or “stimming” refers to self-soothing, mostly unconscious repetitive sounds or movements. Almost everyone stims: think hair twirling or nail-biting.

For folks with conditions such as autism or attention deficit hyperactivity disorder (ADHD), stimming may be harder to control, however.

Stimming behavior can look very much like tics.

Tics are also repetitive movements, but unlike stims, they are involuntary, anticipated, and not particularly pleasurable. Tics are features of Tourette syndrome (TS) and other Tic disorders (TD).

While ADHD stimming differs from autism spectrum disorder (ASD) stimming and tics, ADHD, ASD, and TD symptoms overlap. If you have ADHD, you may also have another coexisting condition that causes stimming or tics.

If your stimming does not put you at risk or cause you embarrassment, you may choose not to worry about it.

But if your stims worsen your distractedness or seem to be intensifying, having a medical professional test for coexisting conditions may ensure you get the most effective treatment.

Vocal stimming involves making sounds with your mouth or breath. Examples of vocal stimming include:

  • verbal noises
  • humming
  • shrieking
  • repeating words or phrases, including from books, movies, or echoing someone else

Auditory stimming is related to vocal stimming. Some common auditory stims involve:

  • tapping tables
  • tapping ears
  • snapping fingers

Types of stims

Stimming can engage any one of the senses or parts of the body. Whether or not you have ADHD, you may find yourself engaging in the following stims:

  • touch stimming, such as skin rubbing, hand moving, and tapping
  • motor stimming, including pacing, rocking, and spinning in circles
  • taste stimming (involves smell and taste) for example, smelling objects or people, licking objects, or putting objects in your mouth

Is vocal stimming a symptom of ADHD?

Verbal stims that may be common with ADHD are often symptoms of hyperactivity and impulsivity, as presented by the National Institute of Mental Health (NIMH):

  • blurting
  • humming
  • singing or repetitively quoting from a movie or video

What are some ADHD stims?

Other ADHD stims involve different senses and parts of the body.

ADHD stims often look like restlessness:

  • fidgeting
  • biting nails
  • biting inside of cheeks
  • foot-tapping
  • pacing
  • knuckle cracking
  • spinning
  • jumping

ADHD stims may look like disinterest or even defiance. Still, they often result from unconscious efforts to cope with brain differences that make daily functions challenging.

These include:

  • executive functioning challenges
  • self-regulatory challenges
  • impulsivity

Causes

A 2017 causal analysis found that hyperactivity, impulsivity, and inattention associated with ADHD influence repetitive behaviors or stimming in various ways:

Restlessness. Restlessness may lead to a decreased ability to control motor behaviors. While most folks blurt, hum, or fidget from time to time, people with ADHD have a harder time stopping once they start.

Sensory processing differences. If you live with ADHD, one feature of your experience may be hypersensitivity. This means that your mind can’t always discern which sound or sensation of many is important.

If you find yourself chewing your pen or singing while working, you may be unconsciously offering yourself the sensory input needed to stay present and grounded in your body and the task.

Impulsivity. Impulsivity with ADHD can make it hard to delay gratification. Most people stim because it feels good immediately. Once the habit of stimming starts, it reinforces itself.

Triggers

Triggers for ADHD stimming involve situations or tasks that tax executive functioning skills or worsen challenged impulse control, hyperactivity, and self-regulation. Some examples include:

  • boredom
  • overwhelm when coping with prioritizing tasks
  • distractions
  • poor sleep can worsen executive functioning skills
  • lack of exercise or mandatory sitting for long periods
  • fear, stress, or excitement

Autism spectrum disorder

Often, ADHD stimming looks similar to the repetitive verbal stims and stereotyped movements performed by people with autism spectrum disorder (ASD).

ASD is a spectrum of conditions that affect speech and nonverbal communication.

Some vocal stims associated with ASD include shrieking, humming, and echoing words or phrases from books or movies.

ADHDASD
stims cope with feelingsstims communicate feelings
differences in brain regions responsible for repetitive speech patternsdifferences in brain regions responsible for repetitive speech patterns
last longer than ADHD stims

A 2017 analysis of the relationship between ADHD and ASD found that up to 65% of children with ADHD have clinical symptoms of ASD. Treatment options for both conditions may also overlap.

One observation the analysis explores — though more research is needed — is that the condition overlap may support the theory ADHD is a mild subset of ASD.

Tourette syndrome and tic disorders

Tourette syndrome (TS) is a severe tic disorder that develops at a young age. While tics are repetitive movements that look like stims, the experience of tics is different.

ADHDTS
stims are unconscious but can be stopped and startedtics feel uncontrollable
stims can be soothing or focusingtics are unpleasant
relief is felt from doing the stimrelief is felt when they’re over
differences in the brain’s dopamine transmitters and receptors may be a factordifferences in the brain’s dopamine transmitters and receptors may be a factor

Tics usually onset with a precursor feeling, generalized or local to one body part.

While ADHD does not cause tics, one systematic review finds:

  • the brain differences may increase the chances of developing both conditions
  • 80% of folks with ADHD have a co-occurring condition
  • 7% of children with ADHD also have TS

Even if you have a mild tic disorder with ADHD, you may be directed to treat ADHD symptoms first.

Reviewers suggest that the symptoms of TD may be helped by treatments for ADHD.

Stims with ADHD are not harmful and can be helpful to self-regulate. But if stims are causing more disruption than self-soothing, there are options.

Often the recommended prescription, behavior, and treatments for ADHD can reduce stims, even when co-occurring disorders are present.

Medication

Effective medications for ADHD can help with stimming behaviors. Stimulants commonly prescribed are:

If you or your doctor are worried about side effects, you might try nonstimulant medications:

Executive functioning help

Having a coach assist you with executive functioning challenges may relieve stress and remove triggers for stimming. A trained professional can help you develop skills in:

Behavioral therapy

If you’re concerned about how your stims appear or if they’re distracting, you may wish to ask about “habit reversal training.” You can learn to substitute:

  • gum chewing for hair chewing
  • toy squeezing for blurting out responses
  • stretching for jumping up at inopportune times

Lifestyle changes

You may be able to reduce stress and stimming behaviors by managing other triggers. Changes to consider include:

  • more sleep
  • planned exercise breaks
  • planned rewards for work accomplished

Self-advocacy

Living with a mental health condition may often mean self-advocating for your wellness at work, with family, or in social settings. On the job or at school, this might look like:

  • Proactively inform your boss or co-workers, teachers, or classmates you collaborate closely with that your brain uses vocal stims to focus, and it doesn’t mean you’re not listening.
  • Ask whether they find it distracting, and would lowering your volume or putting your hands beneath the table be a fair accommodation?

Treatments for executive functioning challenges such as medication or coaching might help relieve stress and reduce stimming.

You may wish to consult your doctor about stimming symptoms if they worsen or if you develop tics.

But if your stims soothe you and keep you on task, you may choose simply to live with them.