WEDNESDAY, Feb. 10 (HealthDay News) -- Scientists report they've gained greater understanding of fragile X syndrome, which causes autism and mental retardation, by studying the brain circuitry of mice.

The researchers, whose findings are published in the Feb. 11 issue of Neuron, say they're developing insights into why some people with fragile X are hypersensitive to things they sense through smell, touch, sound and sight. The cause, they believe, is a developmental delay in a brain circuit that's essential for processing sensory information.

This hypersensitivity can lead to symptoms like withdrawal from society, hyperarousal and anxiety.

"A central feature of fragile X syndrome is an alteration in sensory processing that manifests in early infancy and progressively worsens through childhood," senior study author Dr. Anis Contractor, of the Northwestern Feinberg School of Medicine in Chicago, said in a news release from the journal's publisher. "Little is known about how disruptions in the part of the brain that process sensory information, called the sensory cortex, contribute to these deficits."

The researchers focused on the development of synapses in the brain and how disruption might affect sensory perceptions.

More information

The U.S. National Library of Medicine has more on fragile X syndrome.