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FMRI Brain Imaging Study of Presentiment

This study investigates the phenomenon of presentiment, the apparent psycho-physiological effect of a future emotional 'cause', using FMRI brain imaging. The study explores the differentiation of emotions and the possible source of this phenomenon.

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FMRI Brain Imaging Study of Presentiment

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  1. A FMRI Brain imaging Study of Presentiment . Dick J. Bierman & Steven H. Scholte Universities of Amsterdam & Utrecht (NL) ISLIS Conference, Aug. 22-Aug. 27, Japan

  2. What went on before? Presentiment experiment Presentiment is reported as the apparent psycho-physiological effect of a future emotional ‘cause’.

  3. Procedure • Subject sits relaxed with electrodes attached • Gets about 40 exposures of randomized neutral and calm stimuli • Skin conductance is averaged separately for emotional and neutral stimuli • Before, during and after stimulus • Baseline fixed at ~ -7.5 seconds

  4. Blank screen Or Calm Subject Hits Button Random!! baseline 5 0 Procedure Presentiment ‘trial’ Skin Conductance Time

  5. For example the following sequence could arise c c e c e c c e We analyze this by averaging over the condition

  6. stimulus Emotional Presentiment? Calm Results First Subject (Radin-1) Before During After

  7. Presentiment! Results all Subjects (Radin-1) Emotional Calm

  8. Replications

  9. Replications • Amsterdam University • Edinburgh University • Lab. For Fundamental Research, Palo Alto • Cornell University (in progress) • Budapest • POST HOC in already published data: • Antonio Damasio (Iowa university) • Alfons Hamm (Uni.Greifswald)

  10. Erotic presentiment Calm Results re-analysis Hamm’s data stimulus

  11. So What Next? • Can we differentiate between different emotions? • Can we locate the source of this phenomenon?

  12. Brain scanner, Amsterdam Summer 2001

  13. Event Related Design • 10 subjects • 48 pictures (events) • ~ 32 neutral, ~ 8 erotic, ~ 8 violent • 4.2 seconds exposure time • 16.8 seconds for one trial (= 8 volumescans) • 1 vol: 22 slices, slice resolution: 64 * 64

  14. Analysis procedure (1) • Dependent var: BOLD signal per voxel (Blood Oxygenation Level Dependent) • Pre-processing: • Slice time correction • Linear trend removal • 8 mm spatial smooting • No further smoothing in time domain

  15. Analysis Procedure • SPATIAL: • Fit data to a General Linear Model • Predictors : neutral, erotic, and violent stim. • Result: Regions of Interest with significant fit. • TEMPORAL (restricted to ROI): • Event related averaging of BOLD per condition • t-test of average BOLD signals in ROI

  16. Contrast between emotional and neutral conditon. Brain regions which have a significant fit with emotional stims and neutral stim as predictor

  17. Screen Dump of analysis software Output Input: Single individual’s brain signals

  18. Event related averaging erotic neutral stimulus Brain-map with ROI’s Plot for BOLDsignal for the whole experiment Erotic Presentiment effect at time: -4 seconds. Td = 2.89 df= 39 p < 0.01

  19. violent ROI: -51, -78, 1 erotic

  20. violent ROI: -1,-80, 37

  21. Pooling of data • Mapping in Talairachspace • Loss of signal due to individual differences • So:separate male and female

  22. all female All female: Erotic & Violent presentiment (t ~ 1.75, df=158, p<0.05 o.t.)

  23. all male All male: Erotic presentiment (t ~ 2.1, df=226, p<0.01 o.t.)

  24. Considered ‘Normal’ explanations • Artefacts Introduced by software • Hemodynamic curve • Smoothing • Chance fluke or over analysis • Incorrect Randomization • Subject Strategies

  25. Subject Strategies A subject strategy reflects itself in the anticipation being a systematic function of the history of stimuli so far presented.

  26. Subject anticipatory Strategies • Subject strategy: Ai = f(P1…P i-1) • Based upon Gamblers Fallacy • In spite of the fallacy: produces normal effect • Goes to 0 if N goes to infinity • Simulation using ACTUAL random sequence • A increases after each neutral (sigmoid function) • A is reset after emotional stimulus

  27. Results SS simulation Over-all Subjects the explained effectsize is 2% after N=48 trials

  28. Reasons to reject SS explanation • Explained effect is too small • Does not explain spatial qualitative differences between emotions and gender • NO neutral anticipation observed!!!!!

  29. Conclusion • This study should be seen as exploratory • But justifies further research (as usual) • And theoretical speculation: • Could Consciousness be a Feynman-Wheeler’s multiparticle coherent absorber and therefore allow for advances waves? • Replication study will focus on the coherence of brain states

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