Methylphenidate Modulates Functional Network Connectivity to Enhance Attention

J Neurosci. 2016 Sep 14;36(37):9547-57. doi: 10.1523/JNEUROSCI.1746-16.2016.

Abstract

Recent work has demonstrated that human whole-brain functional connectivity patterns measured with fMRI contain information about cognitive abilities, including sustained attention. To derive behavioral predictions from connectivity patterns, our group developed a connectome-based predictive modeling (CPM) approach (Finn et al., 2015; Rosenberg et al., 2016). Previously using CPM, we defined a high-attention network, comprising connections positively correlated with performance on a sustained attention task, and a low-attention network, comprising connections negatively correlated with performance. Validating the networks as generalizable biomarkers of attention, models based on network strength at rest predicted attention-deficit/hyperactivity disorder (ADHD) symptoms in an independent group of individuals (Rosenberg et al., 2016). To investigate whether these networks play a causal role in attention, here we examined their strength in healthy adults given methylphenidate (Ritalin), a common ADHD treatment, compared with unmedicated controls. As predicted, individuals given methylphenidate showed patterns of connectivity associated with better sustained attention: higher high-attention and lower low-attention network strength than controls. There was significant overlap between the high-attention network and a network with greater strength in the methylphenidate group, and between the low-attention network and a network with greater strength in the control group. Network strength also predicted behavior on a stop-signal task, such that participants with higher go response rates showed higher high-attention and lower low-attention network strength. These results suggest that methylphenidate acts by modulating functional brain networks related to sustained attention, and that changing whole-brain connectivity patterns may help improve attention.

Significance statement: Recent work identified a promising neuromarker of sustained attention based on whole-brain functional connectivity networks. To investigate the causal role of these networks in attention, we examined their response to a dose of methylphenidate, a common and effective treatment for attention-deficit/hyperactivity disorder, in healthy adults. As predicted, individuals on methylphenidate showed connectivity signatures of better sustained attention: higher high-attention and lower low-attention network strength than controls. These results suggest that methylphenidate acts by modulating strength in functional brain networks related to attention, and that changing whole-brain connectivity patterns may improve attention.

Keywords: fMRI; functional connectivity; methylphenidate; neuromarker; predictive marker; sustained attention.

MeSH terms

  • Adult
  • Attention / drug effects*
  • Brain / diagnostic imaging
  • Brain / drug effects*
  • Central Nervous System Stimulants / pharmacology*
  • Connectome*
  • Female
  • Healthy Volunteers
  • Humans
  • Inhibition, Psychological
  • Magnetic Resonance Imaging
  • Male
  • Methylphenidate / pharmacology*
  • Neural Pathways / diagnostic imaging*
  • Neural Pathways / drug effects
  • Neuropsychological Tests
  • Reaction Time / drug effects
  • Young Adult

Substances

  • Central Nervous System Stimulants
  • Methylphenidate