title: Volumetric and Correlational Implications of Brain Parcellation Method Selection: A 3-Way Comparison in the Frontal Lobes.
abstract: OBJECTIVE
  The aims of this study were to compare distinct brain frontal lobe parcellation methods across 90 brain magnetic resonance imaging scans and examine their associations with cognition in older age.
  
  
  METHODS
  Three parcellation methods (Manual, FreeSurfer, and Stereology) were applied to T1-weighted magnetic resonance imaging of 90 older men, aged ∼ 73 years. A measure of general fluid intelligence (gf) associated with dorsolateral frontal regions was also derived from a contemporaneous psychological test battery.
  
  
  RESULTS
  Despite highly discordant raw volumes for the same nominal regions, Manual and FreeSurfer (but not Stereology) left dorsolateral measures were significantly correlated with gf (r > 0.22), whereas orbital and inferior lateral volumes were not, consistent with the hypothesized frontal localization of gf.
  
  
  CONCLUSIONS
  Individual differences in specific frontal lobe brain volumes--variously measured--show consistent associations with cognitive ability in older age. Importantly, differences in parcellation protocol for some regions that may impact the outcome of brain-cognition analyses are discussed.
authors.affiliation: From the *Brain Research Imaging Centre, †Centre for Cognitive Ageing and Cognitive Epidemiology, ‡Department of Psychology, and §College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom; ∥Department of Computer Science, Lagos State University, Lagos, Nigeria; ¶Scottish Imaging Network, a Platform for Scientific Excellence (SINAPSE) Collaboration; and #Geriatric Medicine, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Simon R
authors.initials: SR
authors.lastname: Cox
authors.forename: Tahlia I
authors.initials: TI
authors.lastname: McKenzie
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Aribisala
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Royle
authors.forename: Sarah E
authors.initials: SE
authors.lastname: MacPherson
authors.forename: Alasdair M J
authors.initials: AM
authors.lastname: MacLullich
authors.forename: Mark E
authors.initials: ME
authors.lastname: Bastin
authors.forename: Joanna M
authors.initials: JM
authors.lastname: Wardlaw
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Deary
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Ferguson
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods*; D003072:Cognition Disorders / Q000473:pathology*; D005625:Frontal Lobe / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D009929:Organ Size; D015203:Reproducibility of Results