title: The nature of processing speed deficits in traumatic brain injury: is less brain more?
abstract: The cognitive constructs working memory (WM) and processing speed are fundamental components to general intellectual functioning in humans and highly susceptible to disruption following neurological insult. Much of the work to date examining speeded working memory deficits in clinical samples using functional imaging has demonstrated recruitment of network areas including prefrontal cortex (PFC) and anterior cingulate cortex (ACC). What remains unclear is the nature of this neural recruitment. The goal of this study was to isolate the neural networks distinct from those evident in healthy adults and to determine if reaction time (RT) reliably predicts observable between-group differences. The current data indicate that much of the neural recruitment in TBI during a speeded visual scanning task is positively correlated with RT. These data indicate that recruitment in PFC during tasks of rapid information processing are at least partially attributable to normal recruitment of PFC support resources during slowed task processing.
authors.affiliation: Psychology Department, Pennsylvania State University, State College, PA, USA. fhillary@psu.edu
authors.forename: Frank G
authors.initials: FG
authors.lastname: Hillary
authors.forename: Helen M
authors.initials: HM
authors.lastname: Genova
authors.forename: John D
authors.initials: JD
authors.lastname: Medaglia
authors.forename: Neal M
authors.initials: NM
authors.lastname: Fitzpatrick
authors.forename: Kathy S
authors.initials: KS
authors.lastname: Chiou
authors.forename: Britney M
authors.initials: BM
authors.lastname: Wardecker
authors.forename: Robert G
authors.initials: RG
authors.lastname: Franklin
authors.forename: Jianli
authors.initials: J
authors.lastname: Wang
authors.forename: John
authors.initials: J
authors.lastname: DeLuca
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D001930:Brain Injuries / Q000473:pathology / Q000503:physiopathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D009434:Neural Pathways / Q000503:physiopathology; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology; D011930:Reaction Time; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen