Can anxiety cause slow processing speed in children?
Anxious kids often appear to be hesitant and unsure of themselves. They take a long time to make decisions and may be slow to complete tasks. Interestingly, approximately 20% of children diagnosed with Generalized Anxiety Disorder also display signs of slow processing speed. This suggests that many kids with anxiety will fall behind their peers because they can’t keep up with the pace of work.
There are many reasons for believing that anxiety is related to slow processing speed. Anxious kids who are stressed, reluctant to make a mistake, or “frozen in their tracks” are invariably inefficient and slow to process information and complete tasks. They may display signs of test anxiety that can cause them to “blank out” when taking a test, so fearful of getting the wrong answers that they do not complete as many items as their peers. But test anxiety is actually quite different from a cognitively-based slow processing speed.
However, many observations of anxious kids suggest that the symptoms of anxiety could exacerbate slow processing speed. For example, children with Obsessive Compulsive Disorder might appear to complete work slowly because they have developed internal rules such as needing to re-read an entire passage if they make a mistake while reading. Perfectionism can also cause slow output in writing when children “need” to form letters and numbers so that they are without flaw.
Other signs of anxiety such as obsessive ideation and rumination can interfere with concentration and the capacity to process information efficiently. Social anxiety, including concerns about the judgment of peers, can cause kids to become overly cautious and slow in completing tasks. Sleeping and eating disturbances associated with anxiety can result in a lack of energy, fatigue, and poor concentration contributing to slower processing speed.
Interestingly, studies have found that slow processing speed is not more common in children whose only diagnosis is anxiety or depression. Instead, follow-up studies suggest that anxiety as a comorbid disorder with ADHD, Inattentive Type results in slower processing speed than it does in kids with ADHD, Hyperactive or Combined Type who also have a diagnosis of Anxiety Disorder. These children may also be identified as displaying a sluggish cognitive tempo, a construct developed by Russell Barkley, that describes kids who daydream, seem spacey, lack energy, and are withdrawn and slow moving.
Another study, which examined the relationship between depression, Oppositional Defiant Disorder, and anxiety with processing speed found that kids with Oppositional Defiant Disorder and and anxiety disorders performed well on measures of processing speed. Those diagnosed with Generalized Anxiety Disorder (GAD) – why this abbreviation when there aren’t any for other D/s’s – seem to use anxiety is a motivating rather than a paralyzing force. When Anxiety Disorder was added to other clinical disorders, including ADHD,Combined Type and Depression, processing speed actually improved. Therefore the current research suggests that while feelings of anxiety can acutely impact processing speed, children with a singular diagnosis of Anxiety Disorder do not process information slowly unless they also have a diagnosis of ADHD, Inattentive Type.
An alternative view suggests that slow processing speed might cause anxiety. This perspective fits many of my observations as a clinical child psychologist. Children become more aware of their slow processing in middle to late elementary school, and become more stressed and anxious about their difficulty in keeping up with their peers and meeting their own and parents’ expectations. These kids may not have been aware of their struggles with processing speed when younger. As they got older they may have begun to notice that they are the last to finish a test, can’t keep up with the pace at an after- school job, or struggle with the banter that takes place with their peers.
A recent study supports this notion. Researchers found that measures of processing speed and reaction time collected at age 16 predicted mental health status 20 years later. In this study, 16-year-olds with slow processing speed were at increased risk for anxiety and depression when it was assessed at age 36, regardless of other factors.
This study strongly supports the need to help kids with slow processing speed as early as possible. Early identification and support not only help them to keep up with the demands of school and society but also inoculates them from anxiety and depression that can be exacerbated by the long-term impact of slow processing speed.
Featured image: Flickr user breity