Diff for "ParametricModulation" - Methods
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Ian has written a technical note in latex - attachment:parametric_latex.tex Ian has written a technical note in latex:

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ttp://imaging.mrc-cbu.cam.ac.uk/svn/cbumethods/parameters/trunk/docs/smoothed.tex

Parametric modulation

The problem of constrained modeling of parametric modulation across events, allowing for flexible relationship between signal and parameter.

Work so far

The event-related study of Brett et al:

http://www.mrc-cbu.cam.ac.uk/~matthew/abstracts/ER/er_analysis.html

Parametric modulation approach described in:

  • Estimating effects on effects using the Varying Coefficient Models by Ferath Kherif, Emmanuel A Stamatakis, Cristina Ramponi,Matthew Brett, Ian Nimmo-Smith, and Lorraine K Tyler

http://www.mrc-cbu.cam.ac.uk/Statistics/Methods/Resources/ferath_hbm2005.pdf

The dataset

Described in Brett et al abstract and poster above.

Visual checkerboard events at random intervals. Sessions for which events are rapid (mean ISI 1 second) to slow (mean ISI 10 seconds). Evidence that interval between current and last event influences height and possibly shape of response. We wanted to be able to fit a curve relating the height of the event to the parametric modulator of time since last event.

We used region of interest time courses from the visual cortex to stabilize the signal.

Code so far

Implemented in matlab, by Ferath and Ian. No modeling of

Ian has written a technical note in latex:

http://imaging.mrc-cbu.cam.ac.uk/svn/cbumethods/parameters/trunk/docs/smoothed.tex

Plan

Put

Approach to problem

  • Proper modeling of autocorrelation - maybe using R routines
  • Modeling on ROI time-courses

None: ParametricModulation (last edited 2013-03-08 10:28:25 by localhost)