Repetition Suppression Study of non Mirroring Mirror Neurons

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					Repetition Suppression Study of
 non-Mirroring Mirror Neurons
  Geoff Bird, Hannah Widmann, Clare
  Press, Caroline Catmur, James Kilner,
               Celia Heyes
        Mirror Neurons and RS
• Pairs of Action Stimuli – Obs/Exe and Exe/Obs
• Cross modal RS for repeat vs non-repeat trials.
• 96 repetitions, 43mins, 10Ss, 16 slices on IFG.

                                   Kilner et al 2009, JoN
                 Alternative RS Design
• Unimodal (exe) study of action planning.
• 19 Ss, 4sec action execution event, 4sec rest.
  36 trials (~5min) in total. Hamilton & Grafton 2008, HBM

               Non-Mirroring MNs & RS
                   SESSION 1              SESSION 2            SESSION 3
                 Ob-exe   X      Pre    Ob-ob   X      Pre    Ob-exe   Pre    Pre
TRAINING                  Y      Pull           Y      Pull            Pull   Pull
 Stim   Resp     Exe-ob   Pre    X              Pre    X      Exe-ob   Pre    Pre
 X      Pre               Pull   Y              Pull   Y               Pull   Pull
 Y      Pull     Ob-exe   X      Pull   Ob-ob   X      Pull   Ob-exe   Pre    Pull
                          Y      Pre            Y      Pre             Pull   Pre    Non-Repeat
                 Exe-ob   Pre    Y              Pre    Y      Exe-ob   Pre    Pull

                          Pull   X              Pull   X               Pull   Pre
2 (Suppression: Long vs Short) x 2 (Repeat vs Novel) x 2 (ObsExe vs ExeObs)

Aobs (250ms) Bexe (Jit 2secs) Bobs (250ms) Aexe (Jit 2 secs) Aexe (250ms) Bobs etc

8 conditions x 32 reps per cell = 256 trials x (1125ms mean gap duration + 750ms stim
duration) = 8min

3 sessions = 24mins + 15mins = 39mins per subject (45mins)

45mins * 20subjects = 15hrs scanning time.

Analysis – Full-Factorial ANOVA using SPM8. Contrast repeat vs non-repeat trials after
long and short delays. Check to see whether obs/exe or exe/obs makes a difference.

32-channel head coil. Potentially reduce coverage for faster scanning (IFG?)

Custom-built response apparatus – borrowed from James Kilner.