Browsing by Author "Bell, Tiffany"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- ItemOpen AccessEffects of Transcranial Direct Current Stimulation on GABA and Glx in Children: A pilot study(Public Library of Science (PLoS), 2020-01-07) Nwaroh, Chidera; Giuffre, Adrianna; Cole, Lauran; Bell, Tiffany; Carlson, Helen L.; MacMaster, Frank P.; Kirton, Adam; Harris, Ashley D.Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that safely modulates brain excitability and has therapeutic potential for many conditions. Several studies have shown that anodal tDCS of the primary motor cortex (M1) facilitates motor learning and plasticity, but there is little information about the underlying mechanisms. Using magnetic resonance spectroscopy (MRS), it has been shown that tDCS can affect local levels of gamma-aminobutyric acid (GABA) and Glx (a measure of glutamate and glutamine combined) in adults, both of which are known to be associated with skill acquisition and plasticity; however this has yet to be studied in children and adolescents. This study examined GABA and Glx in response to conventional anodal tDCS (a-tDCS) and high definition tDCS (HD-tDCS) targeting the M1 in a pediatric population. Twenty-four typically developing, right-handed children ages 12-18 years participated in five consecutive days of tDCS intervention (sham, a-tDCS or HD-tDCS) targeting the right M1 while training in a fine motor task (Purdue Pegboard Task) with their left hand. Glx and GABA were measured before and after the protocol (at day 5 and 6 weeks) using a PRESS and GABA-edited MEGA-PRESS MRS sequence in the sensorimotor cortices. Glx measured in the left sensorimotor cortex was higher in the HD-tDCS group compared to a-tDCS and sham at 6 weeks (p = 0.001). No changes in GABA were observed in either sensorimotor cortex at any time. These results suggest that neither a-tDCS or HD-tDCS locally affect GABA and Glx in the developing brain and therefore it may demonstrate different responses in adults.
- ItemOpen AccessResting-State Functional Connectivity Differences in Pediatric Migraine(2019-11-17) Khaira, Akashroop; Bell, Tiffany; Noel, Melanie; Amoozegar, Farnaz; Harris, Ashley D.Pediatric migraines are highly prevalent but not well-understood. Neuroimaging can provide great insight to brain physiology, but few studies have applied imaging to study pediatric migraines. Previous adult literature has shown differences in resting-state functional connectivity (rsFC) in migraine patients compared to controls; however, adult migraine findings may not be directly transferable to children. This study’s aim was to investigate rsFC differences between children with migraine and controls to better understand pediatric migraines. Resting-state functional magnetic resonance imaging (rsfMRI) data from 26 participants (10 controls and 16 migraines), between the ages of 7-16 years. Data was preprocessed and analyzed using FSL. An independent component analysis constrained to 30 components was used to identify resting-state networks across all subjects. Group average spatial maps were regressed into each subject’s dataset for a time course, which was then regressed into the subject-specific spatial maps. Permutation testing compared rsFC differences in the groups while controlling for age. Initial analysis indicated significant rsFC differences (p < 0.05) in two networks. In the frontoparietal network, there is decreased rsFC in the right motor cortex in the migraine group compared to controls. In the hippocampal/amygdala network, there is decreased rsFC in migraine patients in the right amygdala and right hippocampus. The frontoparietal and hippocampal/amygdala networks are relevant to migraine with roles in pain perception and processing, learning, emotion, and memory. Detecting differences in these networks in children with migraine compared to controls shows that even between migraines, there is intrinsically altered rsFC in pediatric migraine patients.