Showing posts with label prefrontal cortex. Show all posts
Showing posts with label prefrontal cortex. Show all posts

Thursday, January 10, 2013

Proximity to Parent Reduces Anxious Youth Stress Response

Functional magnetic resonance imaging provides a powerful tool for understanding anxiety in children as well as adults.

This technique does not use any form of radiation and presents minimal risk for research participants.  We are beginning to better understand important mechanisms of childhood anxiety.

An innovative study of neural stress markers in children examined an important variable in childhood anxiety.  When children are studied in an fMRI scanner, they may or may not have a parent accompany them into the scanner room.  It is important to understand how parental proximity affects the anxiety tasks used in children.

Conner and colleagues from the University of Pittsburgh, Cal-Berkeley and the University of Virginia recently published a study related to this topic in the journal PLOS One. 

In their study, children with clinical anxiety underwent an anxiety task in the fMRI scanner.  Children were allowed to request that their accompanying parent stay with them in the scanner room.  If they did not request this, their parents waited in a external room during the period of the scanning. 

Children in the scanner were presented a series of words that included words with a cognitive element of physical danger, i.e. ghost, social anxiety, positive emotions and neutral words.  Children rated each word as positive, negative or neutral using a three-button glove.

The key findings from the study comparing 10 anxious children with parents in the scanning room, 10 anxious children with parents in the waiting room and 10 non-anxious control children with parents in the waiting room:
  • Anxious children with parents in the waiting room showed increased brain response compared to control children to anxiety words in three areas known to be related to stress response: hypothalamus, the ventromedial prefrontal cortex and the left ventrolateral prefrontal cortex
  • This stress response was attenuated in anxious children with parents in the scanning room.  Their level of response was very similar to control children.
The figure at the right highlights the medial frontal cortex.  This area was found to be important in the child stress response in the current study and is sensitive to parental proximity.

The authors of this study concluded that for anxious youth, "caregivers may act as emotion regulators".  They note that treatments that facilitate transfer of emotional regulation of anxiety from parental support to an internal self-mechanism may play a key role in advancing  anxiety disorder treatment in children.

Another important implication in this study is the potential role of parental proximity in comparing imaging studies across research centers.  Disparate results may be related to differing rates of parental proximity between research centers.

It is important to note this study did not use a randomized design as children were allowed to self-select whether they had a parent in the scanning room.  Nevertheless, this study proposes a brain mechanism related to a parental role in anxiety regulation for children who suffer from an anxiety disorder.  Interested readers can access the free full text of this manuscript by clicking on the link in the citation below.

Photo of blue curaco from San Diego Zoo from the author's files.

Image of prefrontal cortex is a screenshot from the iPad app 3D Brain.

Conner OL, Siegle GJ, McFarland AM, Silk JS, Ladouceur CD, Dahl RE, Coan JA, & Ryan ND (2012). Mom-It Helps When You're Right Here! Attenuation of Neural Stress Markers in Anxious Youths Whose Caregivers Are Present during fMRI. PloS one, 7 (12) PMID: 23236383

Monday, December 31, 2012

Top Ten Brain Posts 2012: #1 ADHD and IQ

The most highly viewed Brain Post of 2012 examined a study of brain development, IQ and ADHD.

ADHD rates are increased in lower IQ children but can be found in those with normal and above normal IQ performance.  

This study looked at a sensitive measure of brain development and compared the structural brain patterns of children with ADHD with low IQ and children with ADHD with normal IQ.

The study found two distinct patterns related to brain development in these two groups:
Low IQ children with ADHD showed delay brain gray matter development in the prefrontal cortex region compared to control children
High IQ children with ADHD had reduced gray matter volume throughout the brain but no focal developmental abnormality patterns

These results suggest more than one brain developmental abnormality in ADHD.  Future studies of brain structure, brain function and genetic risk factors will need to consider controlling for IQ performance.

Photo of blue heron and snowy egret hunting together is from the author's files.