Types of sensory dysfunction

Parham and Mailloux (2015) identified four categories of sensory integration problems:

• Sensory modulation problems
• Sensory discrimination and perceptual problems
• Vestibular bilateral functional problems
• Praxis problems

Sensory modulation

Problems with sensory modulation occur when the brain either over responds to, or under responds to sensory information. 

For some people the degree to which their brain under or over responds impacts on things they need to do in everyday life. As a result, they could become distressed or miss out on things that could keep them safe. Problems with modulation can cause the person to become anxious, fearful, angry and frustrated.  Some people develop unusual or untoward behaviours, e.g. removing their clothes, not washing, flapping their hands,  or withdrawal from social contact.  Responsiveness can be dependent on a situation.

Sensory discrimination and perceptual problems

This occurs when the brain has difficulties making sense of the sensory information it receives. The person then struggles to interpret subtle differences in the sense, e.g. feeling two different points of touch that are close together. The brain also has difficulty with giving meaning to the information it is receiving.  A person can appear clumsy, use too much or too little force when doing things, struggle to read or to find objects in cluttered environments.

Vestibular-bilateral functional problems

These problems are a result of problems with our vestibular sense and can result in poor balance and difficulties with coordinating two sides of the body.

Praxis problems

Praxis is how our brain plans for and carries out movements we have not done before. For children this could be learning to jump, for adults it may be learning to drive . 

A person may have dyspraxia or motor planning problems.  People with dyspraxia often look clumsy or awkward in their movements.

There are two types of praxis difficulties associated with underlying sensory issues; somatodyspraxia and visuodyspraxia. Somatodyspraxia is when a person has problems with praxis as well as problems with processing touch and proprioceptive senses, while visuodyspraxia is a problem with praxis and visual processing.