Electrodermal responses to sensory stimuli in individuals with fragile X syndrome: A preliminary report

Abstract

The fragile X mutation and fragile X syndrome are associated with hyperarousal, hyperactivity, aggression, and anxiety. These may be related to strong reactions to auditory, tactile, visual, and olfactory stimuli [Hagerman, 1996b; Hagerman and Cronister, 1996]. However, almost no data exist describing hyperarousal and sensory sensitivity in individuals with the fragile X mutation. This study establishes a reliable laboratory paradigm for examining reactions to sensory stimuli. We found the pattern of electrodermal responses (EDRs) to stimulation in one sensory modality predicted the pattern of EDRs in four other sensory systems. In addition, the EDR pattern of individuals with the fragile X mutation was related to their FMR-protein expression. Finally, EDRs in individuals with fragile X syndrome were significantly different from those of normal controls, demonstrating greater magnitude, more responses per stimulation, responses on a greater proportion of trials, and lower rates of habituation. The findings support the theory that individuals with fragile X syndrome have a physiologically based enhancement of reactions to sensations. Because electrodermal activity indexes sympathetic nervous system activity, the data suggest that the over-arousal to sensation may involve the sympathetic system.

Sensory Processing Disorder in a Primate Model: Evidence From a Longitudinal Study of Prenatal Alcohol and Prenatal Stress Effects

“…This scale was developed by adapting procedures from sensory processing assessments for children (Baranek & Berkson, 1994;Miller et al, 1999).…”

“…NIH-PA Author Manuscript NIH-PA Author Manuscript estimated to occur in 5% of the general population (Ahn, Miller, Milberger, & McIntosh, 2004) and seem to pose a unique challenge for people with developmental disabilities (Baranek, 2002), including autism, attention deficit hyperactivity disorder (ADHD), fragile X syndrome, and other developmental disabilities (Ayres & Tickle, 1980;Baranek, 1999;Baranek & Berkson, 1994;Baranek, Foster, & Berkson, 1997;Cermak & Daunhauer, 1997;Grandin, 1992;Kinnealey, 1973;Larson, 1982;Mangeot et al, 2001;Miller et al, 1999). Understanding the neurobiological processes associated with sensory processing disruptions is important to developing appropriate preventative and intervention approaches.…”

Rescue of behavioral phenotype and neuronal protrusion morphology in Fmr1 KO mice

“…One of the most common clinical features of FXS is heightened sensitivity to sensory stimulation (Frankland et al, 2004;Miller et al, 1999). PPI is a widely used model to study basic sensorimotor processing and has shown to be related to mGluR signaling (Grauer and Marquis, 1999).…”

The cyclic AMP phenotype of fragile X and autism

“…Anxiety is commonly featured with memory deficits in FX individuals Tsiouris and Brown 2004). Although anxiety is difficult to detect in individuals with intellectual disability, behavioral equivalents of anxiety have been reported in FX (Sullivan, Hooper et al 2007) and are likely related to the hypersensitivity and hyperarousal (Cohen 1995) described in electrodermal studies of FX individuals (Miller, McIntosh et al 1999). As Hagerman notes , pharmacologic inhibition of the cAMP second messenger system prevents normal sensitization to sensory stimuli in Aplysia (Kandel and Schwartz 1982) which has direct implications for the abnormal sensitization seen in FX individuals.…”