Addressing Motion and Confounds Issues in Resting fMRI- Application of Multi-echo EPI Scanning
Condition: Attention-deficit/Hyperactivity Disorder
MeSH terms: Attention Deficit Disorder with Hyperactivity
Study type: Observational

Summary: 
      Resting state functional MRI is widely used for studying brain functional networks. However,
      in-scanner head movement and other non-neuronal noise can disproportionately bias
      connectivity estimates, despite various preprocessing efforts. To address these issues, the
      technique combining data acquisition with multiecho (ME) echo planar imaging and analysis
      with spatial independent component analysis (ICA), called ME-ICA, has been develop to
      distinguish BOLD (neuronal) and non-BOLD (artifactual) components based on linear echo-time
      dependence of signals, and has been demonstrated to successfully remove non-neuronal
      confounds. Nonetheless, such research approach has never been applied in psychiatric
      populations. The study aims to fill in the gap as shown in the following.
    

Detailed description: 
      Specific Aims:

        1. To replicate feasibility and efficacy of multi-echo fMRI in removal of non-neuronal
           confounds as shown in work of Kundu and colleagues (2012, 2013)

        2. To characterize intrinsic functional connectivity(iFC) differences between adults with
           attention deficit hyperactivity disorder(ADHD) and healthy volunteers using ME-ICA
           denoising methods. Then compare the results with iFC differences derived from
           single-echo fMRI scan, in order to further separate "authentic" group differences from
           spurious findings introduced by non-neuronal confounds.

        3. To explore the neural signature of in-scanner motion restlessness by comparing
           intrasubject differences in iFC between single-echo and multi-echo fMRI, and
           inter-subject differences between subjects of high- and low- motion levels.

      The investigators plan to recruit 80 participants (40 adults with ADHD, 40 healthy control),
      without current and past history of any systemic physical illness, neither any major
      psychiatric disorder other than ADHD. All the participants will receive psychiatric
      interviews (The Chinese Version of the Kiddie Epidemiologic version of the Schedule for
      Affective Disorders and Schizophrenia, K-SADS-E). They will receive the Wechsler Adult
      Intelligence Scale-3rd edition(WAIS-III) first to ensure their full-scale IQ greater than 80.
      The MRI assessments (T1 imaging, single-echo echo planar imaging(EPI) and multi-echo EPI
      resting-state fMRI) will be subsequently arranged within 2 weeks after
      psychiatric/neuropsychological assessments.

      This study (1) will be the first report in Taiwan in terms of implementation of multi-echo
      EPI for denoise; (2) will be the first report in the world on the functional connective
      differences using multi-echo EPI; (3) will provide further evidence about the mechanism
      underpinning in-scanner motion restless and improve specificity of motion biomarkers by using
      multi-echo EPI.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        The sample consists of 40 adults with ADHD and 40 age-, sex-matched healthy volunteers.