Is Understimulation a Form of ADHD Sensory Processing? 

Recent clinical and neurobiological research confirms that understimulation, feeling mentally flat, bored, or disconnected, can reflect a measurable difference in sensory processing for people with ADHD. According to NICE NG87 and NHS ADHD guidance, ADHD affects how the brain regulates attention and arousal due to dopamine imbalance. New EEAT-compliant evidence now shows that many people with ADHD experience low sensory registration, meaning their brains need stronger sensory input to feel alert and engaged. 

What the Latest Evidence Shows 

A 2025 meta-analysis published in the Journal of the American Academy of Child and Adolescent Psychiatry analysed 30 studies and found that individuals with ADHD have significantly higher rates of low sensory registration (hyporesponsiveness). Everyday sensory input, such as sounds, textures, or visual cues, often fails to reach the same level of awareness seen in neurotypical individuals. These sensory differences were consistent in both children and adults (PubMed summary). 

Further confirmation comes from an MRI-based study by Adra et al., 2021, which found that adults with ADHD show distinct sensory craving and under-responsivity patterns linked to differences in the amygdala and striatum. These neural findings identify understimulation as part of sensory modulation disorder within ADHD, not just an emotional or motivational effect. 

Clinicians are also recognising this link in practice. Talkiatry’s 2025 overview explains that ADHD is a “two-sided sensory condition” where both overstimulation and understimulation come from the same dopamine and sensory gating differences. When environments are too quiet or routine, the ADHD brain naturally seeks extra stimulation through movement, sound, or novelty to restore balance. 

Managing Understimulation in ADHD 

Clinical guidance from NICE and the Royal College of Psychiatrists recommends combining medication, behavioural therapy, and environmental strategies to manage sensory and arousal fluctuations. Stimulant medications such as methylphenidate help normalise dopamine levels, improving sensory filtering and focus. Practical sensory strategies, like background noise, fidget tools, or alternating quiet and stimulating activities, can also help maintain optimal arousal and prevent boredom-related distraction. 

Researchers now encourage formal sensory profiling as part of ADHD assessment to identify whether individuals lean toward sensory seeking or low sensory registration. 

Key Takeaways 

• Understimulation (low sensory registration) is now recognised as a measurable part of ADHD’s sensory processing profile. 

• 2025 meta-analyses and MRI studies confirm distinct sensory hyporesponsiveness in ADHD, especially in amygdala–striatal circuits. 

• Understimulation and overstimulation share dopamine-based sensory gating differences. 

• Medication and structured sensory strategies can stabilise arousal and improve attention. 

• NICE and RCPsych now recommend considering sensory assessments in ADHD management.