BACKGROUND: Numerous functional magnetic resonance imaging (fMRI) studies of the brain-bases of autism have demonstrated altered cortical responses in subjects with autism, relative to typical subjects, during a variety of tasks. These differences may reflect altered neuronal responses or altered hemodynamic response. This study searches for evidence of hemodynamic response differences by using a simple visual stimulus and elementary motor actions, which should elicit similar neuronal responses in patients and controls. METHODS: We acquired fMRI data from two groups of 16 children, a typical group and a group with Simplex Autism, during a simple visuomotor paradigm previously used to assess this question in other cross-group comparisons. A general linear model estimated the blood-oxygen-level-dependent (BOLD) signal time course, and repeated-measures analysis of variance tested for potential cross-group differences in the BOLD signal. RESULTS: The hemodynamic response in Simplex Autism is similar to that found in typical children. Although the sample size was small for a secondary analysis, medication appeared to have no effect on the hemodynamic response within the Simplex Autism group. CONCLUSIONS: When fMRI studies show BOLD response differences between autistic and typical subjects, these results likely reflect between-group differences in neural activity and not an altered hemodynamic response.
BACKGROUND: Numerous functional magnetic resonance imaging (fMRI) studies of the brain-bases of autism have demonstrated altered cortical responses in subjects with autism, relative to typical subjects, during a variety of tasks. These differences may reflect altered neuronal responses or altered hemodynamic response. This study searches for evidence of hemodynamic response differences by using a simple visual stimulus and elementary motor actions, which should elicit similar neuronal responses in patients and controls. METHODS: We acquired fMRI data from two groups of 16 children, a typical group and a group with Simplex Autism, during a simple visuomotor paradigm previously used to assess this question in other cross-group comparisons. A general linear model estimated the blood-oxygen-level-dependent (BOLD) signal time course, and repeated-measures analysis of variance tested for potential cross-group differences in the BOLD signal. RESULTS: The hemodynamic response in Simplex Autism is similar to that found in typical children. Although the sample size was small for a secondary analysis, medication appeared to have no effect on the hemodynamic response within the Simplex Autism group. CONCLUSIONS: When fMRI studies show BOLD response differences between autistic and typical subjects, these results likely reflect between-group differences in neural activity and not an altered hemodynamic response.
Authors: H L Sloan; V C Austin; A M Blamire; J W H Schnupp; A S Lowe; K A Allers; P M Matthews; N R Sibson Journal: Neuroimage Date: 2010-07-12 Impact factor: 6.556
Authors: Stewart H Mostofsky; Stephanie K Powell; Daniel J Simmonds; Melissa C Goldberg; Brian Caffo; James J Pekar Journal: Brain Date: 2009-04-23 Impact factor: 13.501
Authors: E Mark Mahone; Stephanie K Powell; Christopher W Loftis; Melissa C Goldberg; Martha B Denckla; Stewart H Mostofsky Journal: J Int Neuropsychol Soc Date: 2006-09 Impact factor: 2.892
Authors: Marie Gomot; Matthew K Belmonte; Edward T Bullmore; Frédéric A Bernard; Simon Baron-Cohen Journal: Brain Date: 2008-07-31 Impact factor: 13.501
Authors: Donna L Dierker; Eric Feczko; John R Pruett; Steven E Petersen; Bradley L Schlaggar; John N Constantino; John W Harwell; Timothy S Coalson; David C Van Essen Journal: Cereb Cortex Date: 2013-10-27 Impact factor: 5.357
Authors: Michał Podgórski; Katarzyna Matera; Łukasz Olewnik; Tomasz Puzio; Dobromiła Barańska; Piotr Grzelak Journal: J Clin Med Date: 2022-05-22 Impact factor: 4.964
Authors: Alice M Graham; Jennifer H Pfeifer; Philip A Fisher; Weili Lin; Wei Gao; Damien A Fair Journal: Dev Cogn Neurosci Date: 2014-10-16 Impact factor: 6.464
Authors: Anna Blasi; Sarah Lloyd-Fox; Vaheshta Sethna; Michael J Brammer; Evelyne Mercure; Lynne Murray; Steven C R Williams; Andrew Simmons; Declan G M Murphy; Mark H Johnson Journal: Cortex Date: 2015-06-27 Impact factor: 4.027
Authors: Markus Rütgen; Carolina Pletti; Martin Tik; Christoph Kraus; Daniela Melitta Pfabigan; Ronald Sladky; Manfred Klöbl; Michael Woletz; Thomas Vanicek; Christian Windischberger; Rupert Lanzenberger; Claus Lamm Journal: Transl Psychiatry Date: 2019-06-07 Impact factor: 6.222
Authors: Bernadet L Klaassens; Serge A R B Rombouts; Anderson M Winkler; Helene C van Gorsel; Jeroen van der Grond; Joop M A van Gerven Journal: Hum Brain Mapp Date: 2016-09-13 Impact factor: 5.038