Saturday, February 5, 2011

Autism and Executive function deficit

The science behind the study of executive functions is still relatively new even though these abilities have been around long before humans evolved.

We can list a series of skills that a captain needs to sail a ship: Commanding a crew, planning and setting a course. Monitoring the behaviour of the ship, the behaviour of the crew, and the weather, and correcting deficiencies and changing course if conditions warrant; Being able to navigate and negotiate dangerous and technically difficult waters; Anticipating and correcting for future changes in conditions.

Perhaps one could say that while sometimes the ship can sail on auto-pilot some events, not anticipated, will happen that will challenge the ship and its crew and call upon the captain to make a decision that only he can make.

Neurologists know that the ability to initiate and inhibit behavior, the ability to monitor the environments response to our behaviour and to alter our behaviour in response to changing conditions, are all part of an interrelated group of functions centered around the prefrontal cortex.

We think we know about executive functions, but in actuality we take them for granted and don’t know very much about how they work together. We use these skills to shape our own behaviour, but their use in others is often invisible to us because a lot of it has to do with self monitoring, which is something that’s hard to observe in others.

It turns out that adolescents are lacking fully operational executive functions and their prefrontal brains are still developing. That’s why adolescents attend school and are under their parents responsibility and not completely free agents. Sometimes they need their parents executive functioning to survive.

It’s in adolescence that we have to learn to do things even when we don’t want to, to control our impulses, not to fight, not to lie or to steal. We learn to internalize morality and not just to act in order to avoid punishment. It’s in adolescence that we learn to distinguish between true friends and people who are just out to use us.

All these skills we develop as adolescents, require the mastery of executive functions: planning, anticipating consequences, inhibiting impulses, monitoring ourselves and correcting for errors.

“Executive function deficits are disastrous to a normal life” That’s a central point that Nancy Perry makes early on in her book, Adults on the Autism Spectrum Leave the Nest . According to Perry if you have executive function deficits you cannot live as an independent adult. And some kinds of brain-damage and high functioning autistic individuals have deficits in executive function.

It’s most noticeable when these individuals are dealing with novel situations where typical behaviour doesn’t work. They end up in trouble and needing the help of adults who, in effect supply the needed executive function.

These individuals are not retarded, their thought processes are intact. they can be of normal or above average intelligence, they can do well in schools. But things like dealing with money, balancing food and rent, getting and keeping a job, dealing with strangers, and developing a relationship or a friendship are much more difficult for them than for the normal population.

According to Perry, individuals with executive function deficits can’t do two cognitive things at the same time. For instance, they can’t do what they are doing and think about the probable consequences at the same time. “….they don’t think about the morality of their actions, unless directed to stop and think by another person who serves as the missing executive function.”

So autistic individuals will insult others or say hurtful things without thinking about consequences, and will often argue that they are just “telling the truth” when challenged.

Perry relates how she once inadvertently observed her students in a grocery store, mesmerized by the big pyramidal display of soda pop and ending up spending their entire week’s grocery money on pop and chips, with nothing left over to pay for basic groceries.

They have difficulties learning proper behaviour in social situations because they cannot both engage in a social situation and hold in their mind’s eye an awareness of how they are functioning. Most of us do it so easily that we take it for granted. Not so for autistic people.

Hence the reason for the popular theory that autistic people cannot put themselves in someone else’s shoes. This requires doing two things at once in the mind. Imagining we are in someone else’s situation, and comparing it with our own.

They can get along if the environment is more structured but as soon as things happen that are outside of the ordinary they will have trouble functioning, still trying to adhere to behaviour patterns rigidly, without being able to adapt and change course.

Just at the point that the crew needs the captain to intervene and make a decision the captain is not there. The ship founders and heads for the rocks unless there is somebody there to take charge.

To be independent one needs to be able to make adjustments to one’s behaviour according to changes in the environment. You learn to avoid getting killed in traffic. You design your life around a career and a family or some combination of elements. These all require the use of executive functions.

For all young adults becoming independent is an important goal to achieve. But for autistic and brain-damaged individuals becoming independent is very problematic because of their deficiencies in executive function.

2 comments:

  1. well said. Check out Robin Dunbar on executive function and how our evolution has brought us to decisions that affect not only the ship but the ocean we are traveling on. Talk about environmental concerns! What kind of executive functions are taking place in those who choose to make decisions that have put us all at risk? Most autistics don't lie or pull any punches when it comes to speaking what they see as the reality. Us neurotypicals continue to pretend that this mess we have created will be taken care of by someone, eventually and hopefully. Seriously, knowing what we know is enough to stress out anyone. Recall the frog in the frying pan?

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