This is the second in a series of articles on Sensory Processing Disorder (SPD) focusing on the eight sensory systems and the patterns and subtypes.
Dr. Lucy Jane Miller describes three patterns and six subtypes of SPD.
In this article, we will discuss the first pattern of SPD: Sensory Modulation Disorder.
When people think of SPD, the pattern that first comes to mind is usually Sensory Modulation Disorder. This pattern includes the subtypes (A) Sensory Over-Responsivity, (B) Sensory-Under Responsivity, and (C) Sensory Craving.
In general, a person with a Sensory Modulation Disorder has difficulty modulating (regulating) sensory input. Sensory modulation is the ability to respond appropriately to sensory information and remain at an appropriate level of alertness for daily activities.
Sensory Modulation Disorder
A. Over-Responsivity (may also be characterized as sensory avoiding): An exaggerated response of the nervous system to sensory input that most people find tolerable. For example, the nervous system may go into fight-or-flight mode even when no real danger exists. The child might also:
- Present as over-responsive to sensory information in one or more sensory systems.
- Present as tactile defensive and not tolerate clothing or other tactile input (paint, glue, soap) on their bodies.
- Present as fearful of movement (resists swinging or playing on playground equipment).
- Demonstrate difficulty tolerating a wide variety of food textures or smells and appear as a “picky eater” with exaggerated gag responses.
Avoidance behaviors may interfere with the ability to effectively interact with others. A child with over-responsivity is easily overwhelmed by sensory components of tasks.
B. Under-Responsivity (may also be characterized as passive): A lack of response or insufficient response to sensory input. The child can also be unaware of sensory stimuli or demonstrate delayed or less-intense responses than most people. The child may also:
- Appear to be daydreaming or unfocused on what is happening around them.
- Appear to be quiet or a loner.
- Appear uninterested and difficult to engage.
- Demonstrate low endurance.
- Require more sensory input to get their sensory system to respond.
- Mouth objects.
Tasks that do not provide extra sensory input may be perceived as difficult or unrewarding.
C. Sensory-Craving (may also be characterized as sensory seeking): The nervous system of the sensory-craver needs intense input in order for the sensation to be registered. Sensory-cravers seek out intense sensations constantly but are often disorganized due to high levels of random sensory input. They are constantly touching, crashing, and moving, and they have no awareness of personal space. The child may also:
- Demonstrate decreased safety due to impulsiveness and excessive risk taking behaviors.
- Appear to be constant motion but may be clumsy and awkward, frequently falling and bruising (but may not notice injury until pointed out).
- Constantly break their crayons or hurt others unknowingly.
Sensory cravers are in constant movement and may not develop skills needed for gross and fine motor skills.
In my next article, we will focus on Sensory Based Motor Disorder.
From our family to yours,
Melissa Hough, OTR/L, C/NDT
Owner, Children’s Therapy Center, PSC
Melissa Hough, OTR/L, C/NDT is an occupational therapist with 18 years of pediatric experience and certifications in Sensory Integration (SI) and Neuro-Developmental Treatment (NDT). Melissa has a professional and personal perspective when working with children because she is also the adoptive parent of a child with special needs.
For over 10 years, Children’s Therapy Center, PSC has served thousands of families in Louisville, KY, by providing high-quality therapy services and parent education.