Methods 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 v Results CogniCve load leads to a higher noise level in goal directed movements and a lower level of sense of agency Jihye Ryu 1,2 , Elizabeth Torres 1,2,3 1 Rutgers University, Psychology Department 2 Rutgers Center for CogniAve Science 3 Rutgers University , Computer Science Department MoCvaCon • Different levels of intent in our moAons have different signatures of variability (Torres, 2011). • Individuals who pracAce mindfulness report experiencing a higher level of sense of agency (Allen et al., 2009) , while arguably those who have a preoccupied mind may experience a lower level of sense of agency. • Can we characterize different levels of one’s sense of agency using signatures of motor output variability? • This is an experimental paradigm and analyAcs to explore this quesAon. We show preliminary results. Acknowledgements This research is funded in part by The New Jersey Governor’s Council for Medical Research and Treatment of AuAsm and the New Jersey Department of Health References • Allen, M., Bromley, A., Kuyken, W., & Sonnenberg, S. J. (2009). ParAcipants' experiences of mindfulnessbased cogniAve therapy:“it changed me in just about every way possible”. Behavioural and Cogni0ve Psychotherapy, 37(04), 413430 • Haggard, P., Clark, S., & Kalogeras, J. (2002). Voluntary acAon and conscious awareness. Nature neuroscience, 5(4), 382385. • Limerick, H., Coyle, D., & Moore, J. W. (2014). The experience of agency in humancomputer interacAons: a review. Fron0ers in human neuroscience, 8. • Torres, E. B. (2011). Two classes of movements in motor control. Experimental brain research, 215(34), 269283. Future DirecCon • The current study was conducted as a pilot study, and will be conducted on a larger sample with other variaAons of mindfulness pracAces involved. • Given that the speed variability pauern was found only in forward movements (i.e., goal directed movement) suggests that separate brain areas may be involved for efforvul movements, as opposed to automaAc movements. In fact, it is possible that the regions involved in efforvul movement may be related to how we experience sense of agency. • Further studies using devices such as EEG may help to shed light on this conjecture. Experiment Paradigm • Task: The parAcipant touched the screen when a low tone signaled to do so. ACer the touch, the parAcipant heard a high tone that beeped 100ms, 400ms, or 700ms aCer the touch. Then the parAcipant was presented with a sliding scale between 0 to 1 second, to indicate how long they perceived the Ame elapsed between the touch and the high tone. • Control condiAon (Control): Performed 60 trials right aCer becoming familiar with the procedure. • Mindfulness condiAon (Mindful): Performed 60 trials aCer a 10minute guided meditaAon. • CogniAve load condiAon (CogLoad): Performed 60 trials while counAng backwards from 400 by 3. A) Plot the posiAonal trajectory of the poinAng (P) and Ame esAmaAng (T) movement separated by forward (deliberate) and backward (spontaneousuninstructed) moAons. B) Plot the temporal speed profiles (linear velocity, angular velocity, linear acceleraAon, angular acceleraAon) C) Plot frequency distribuAon of the kinemaAc parameter (peak speed, Ame to peak etc.) D) Empirically esAmate the probability distribuAon parameters fiwng histogram in C) using the conAnuous Gamma family of probability distribuAons and their staAsAcs (mu, sigma) E) Plot esAmated parameters on the Gamma plane Red: Forward move for poinCng (P) Blue: Backward move for poinCng (P) Red: Forward move to indicate Cme (T) Blue: Backward move to indicate Cme(T) Forward trajectory Backward trajectory Normalized Peak Accel Time to Peak Accel (ms) Forward trajectory speed profile A) B) C) Control Mindful CogLoad time(sec) 0 0.1 0.2 0.3 0.4 0.5 0.6 0 0.2 0.4 0.6 0.8 1 Gamma pdf 0 0.5 1 1.5 2 2.5 3 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Mean 0.59 0.6 0.61 0.62 0.63 0.64 Standard Deviation 0.02 0.025 0.03 0.035 0.04 0.045 0.05 0.055 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Shape 5 10 15 20 25 Scale 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0.11 0 0.2 0.4 0.6 0.8 1 Gamma pdf 0 1 2 3 4 5 6 7 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Mean 0.15 0.16 0.17 0.18 0.19 0.2 0.21 Standard Deviation 0.004 0.006 0.008 0.01 0.012 0.014 0.016 0.018 0.024 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Shape 1 2 3 4 5 6 Scale 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0 0.2 0.4 0.6 0.8 1 Gamma pdf 0 0.5 1 1.5 2 2.5 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Mean 0.59 0.6 0.61 0.62 0.63 0.64 0.65 0.66 0.67 Standard Deviation 0.025 0.03 0.035 0.04 0.05 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Shape 5 10 15 20 Scale 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0 0.2 0.4 0.6 0.8 1 Gamma pdf 0 1 2 3 4 5 6 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Mean 0.14 0.16 0.18 0.2 0.22 0.24 0.26 0.28 Standard Deviation 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.045 0.05 Control P Control T Mindful P Mindful T CogLoad P CogLoad T Shape 1 2 3 4 5 6 Scale 0 0.05 0.1 0.15 0.2 0.25 Conclusion When participants had cognitive load, the speed profile (e.g., peak angular acceleration and time to peak angular acceleration) showed to have more noise in the movements, than when participants did not have cognitive load (i.e., in control and mindful conditions). Noticeably, this pattern was only found in the forward movement (i.e., goal directed action). Also, when participants had cognitive load, they experienced a lower level of sense of agency, as was shown by the longer perceived time duration between the intended movement and its action effect. Figure from Limerick et al. (2014) Sense of agency was measured using the intenAonal binding method. IntenAonal binding is a phenomenon where an individual perceives the Ame between one’s acAon and its effect to be shorter when the acAon is voluntary, and longer when the acAon is involuntary (Haggard et al, 2002). Number of trials Backward trajectory speed profile Results for ParCcipant A on Normalized Peak Angular AcceleraCon Gamma fit by condiCon Pdf of fiRed gamma funcCon by condiCon Results for ParCcipant B on Normalized Peak Angular AcceleraCon Gamma fit by condiCon Pdf of fiRed gamma funcCon by condiCon Results for ParCcipant A on Time to Peak Angular AcceleraCon Gamma fit by condiCon Pdf of fiRed gamma funcCon by condiCon Results for ParCcipant B on Time to Peak Angular AcceleraCon Gamma fit by condiCon Pdf of fiRed gamma funcCon by condiCon Mean Perceived Time between touch and high tone for 3 parCcipants by condiCon There was a staAsAcally significant difference between condiAons as determined by oneway ANOVA (F(2,177) = 60.65, p <0.001). Fano Factor by condiCon Gamma StaCsCcs by CondiCon Gamma StaCsCcs by CondiCon Fano Factor by condiCon Gamma StaCsCcs by CondiCon Gamma StaCsCcs by CondiCon Fano Factor by condiCon 0 100 200 300 400 500 600 700 800 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 0 100 200 300 400 500 600 700 800 900 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 Angular AcceleraAon (m/s) Angular AcceleraAon (m/s) Time(ms) Time(ms) YposiAon YposiAon XposiAon XposiAon 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0 0.05 0.1 0.15 0.2 0.25 0 0.05 0.1 0.15 0.2 0.25 Fano Factor by condiCon ControlP ControlT MindfulP MindfulT CogLoadP CogLoadT ControlP ControlT MindfulP MindfulT CogLoadP CogLoadT ControlP ControlT MindfulP MindfulT CogLoadP CogLoadT ControlP ControlT MindfulP MindfulT CogLoadP CogLoadT Analyses Peak velocity Peak velocity Sample parsing