Psychologists who studied adults with autism found that the mechanism for using "inner speech," or talking things through in your head is intact, but they don't always use it in the same way as typically developing people do.

The researchers found that the tendency to "think in words" is also strongly linked to the extent of a person's communication skills, which are rooted in early childhood.

The results suggest teaching autistic children how to develop inner speech skills may help them cope with daily tasks later in life. It also suggests children with autism may do better at school if they are encouraged to learn their daily timetable verbally rather than using visual plans, which is currently a common approach.

Autism, which affects around one percent of the population worldwide, includes a spectrum of disorders ranging from mental retardation and a profound inability to communicate, to relatively milder symptoms such as seen in people with high-functioning autism or Asperger's syndrome.

Among core features of autism are poor communication skills and difficulties with social engagement.

"Most people will 'think in words' when trying to solve problems, which helps with planning or particularly complicated tasks," said David Williams of Durham University's department of psychology, who led the study.

Typically developing children tend to talk out loud to guide themselves through tricky tasks, and only from about 7 years old do they talk to themselves in their heads to try to solve problems, he said. How good people are at it is partly determined by their communication experiences as a young child.

Williams said children with autism often miss out on the early communicative exchanges, which may explain their tendency not to use inner speech when they are older. He said the lack of inner speech use might also contribute to some of the repetitive behaviors which are common in people with autism.

"Children with autism probably aren't doing this thinking in their heads, but are continuing on with a visual thinking strategy," Williams said in a telephone interview.

"So this is the time, at around six or seven years old, that these teaching methods would be most helpful."

The study, conducted by researchers at Durham, Bristol and City University London and scheduled to be published in an upcoming issue of the Development and Psychopathology journal, involved 15 adults with high-functioning autism and 16 neurotypical adults for comparison.

The volunteers were asked to complete a test of planning ability for which typical people would normally use "thinking in words" strategies.

When the two groups were asked to do the task while also repeating out loud a certain word -- such as "Tuesday" or "Thursday" -- designed to distract them, the control group found the task much harder, while the autistic group were not bothered by the distraction.

"In the people with autism, it had no effect whatsoever," Williams explained. This suggests that, unlike neurotypical adults, participants with autism do not normally use inner speech to help themselves plan.

SOURCE: bit.ly/wOazFh Development and Psychopathology, 2012.

• A Permanent Economic Emergency