title: Asymmetry of prefrontal cortical convolution complexity in males with attention-deficit/hyperactivity disorder using fractal information dimension.
abstract: OBJECTIVE
  Prefrontal cortex, known to be a crucial region for the function of attention, is generally thought to be largely associated with the pathogenesis of attention-deficit hyperactivity disorder (ADHD). Most previous structural imaging studies of ADHD reported abnormality of grey matter volume in prefrontal region. However, volume measure is affected by the size of the interrogated brain, which may cause the inconsistence of the volume based findings. The purpose of the current paper is to use a scale-free measure, fractal information dimension (FID), to assess the prefrontal cortical convolution complexity and asymmetry in ADHD patients.
  
  
  METHODS
  MRI scans from 12 boys with ADHD and 11 controls were carefully processed. Prefrontal cortex was outlined manually. FIDs of bilateral prefrontal cortical surface were examined in each case. Group differences of the bilateral prefrontal cortical convolution complexities and the asymmetry pattern were statistically tested.
  
  
  RESULTS
  We found a left-greater-than-right prefrontal cortical convolution complexity pattern in both groups. However, compared with healthy controls, the left prefrontal cortical convolution complexities of ADHD patients were significantly reduced, resulting in significant reduction of the normal left-greater-than-right cortical convolution complexity asymmetry pattern.
  
  
  CONCLUSIONS
  This study confirms and extends the existing anatomical knowledge about the brains of people with ADHD. The cortical convolution analysis method may also be applied to quantitatively assess changes in other neuropsychiatric syndromes as well.
authors.affiliation: National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing 100080, PR China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Li
authors.forename: Jiefeng
authors.initials: J
authors.lastname: Jiang
authors.forename: Wanlin
authors.initials: W
authors.lastname: Zhu
authors.forename: Chunshui
authors.initials: C
authors.lastname: Yu
authors.forename: Manqiu
authors.initials: M
authors.lastname: Sui
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Tianzi
authors.initials: T
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D002648:Child; D007839:Functional Laterality; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000002:abnormalities* / Q000473:pathology*; D015203:Reproducibility of Results