Un Approccio Sistemistico allo Studio delle Neuroscienze

Transcription

1 Un Approccio Sistemistico allo Studio delle Neuroscienze Domenico Prattichizzo Dipartimento di Ingegneria dell Informazione Universita di Siena CIRA Settembre 2005 Tropea 0

2 Workshop su Robotica e Neuroscienze Centro per lo Studio dei Sistemi Complessi, Universita di Siena, Dicembre D. Prattichizzo and S. Rossi - Special Issue on Robotics and Neuroscience in Brian Research Bulletin. In preparation. An overview of our experience. In cooperation with Simone Rossi (Universita di Siena) and Gabriel Baud-Bovy (S. Raffaele, Milano) 1

3 Outline System Theory and Robotics Neuroscience Modeling (prediction models) Advanced Measurement Perceptual Dissociation (Illusion) Design and VR Rehabilitation and VR 2

4 Modeling / Robotic Methodologies to Study Hands Robot Model Hand Motion/Forces Internal Model? Hand Motion/Forces G. Baud-Bovy and D. Prattichizzo and N. Brogi Does torque minimization yield a stable human grasp? in STAR, Springer Tracks in Advanced Robotics,

5 What is Needed to Study Human Grasp? A biomechanical model of the hand from robotics to learn what are the DoFs Identification of parameters! Measuring the Human Solution The instrumented object The Internal Model able to predict (cost function) 4

6 Modeling / Interacting with the Brain - TMS Lesion-based Neurophysiology A work accident happened on September 13, 1848 to Mr. Phineas Gage. Amazingly, Gage was alive, fully conscious, and experienced no lasting physical handicaps. The wife notes, however, that he was mentally greatly changed, and that once an efficient and capable foreman, he was now increasingly erratic, irritable, and profane. 5

7 Broca s Area (1861) Difficulty in speech production Loss of ability to repeat speach Comprehenzion intact Foot of 3 rd frontal convolution (BA 44) Dr. Paul Broca ( ) 6

8 Wernicke s Area (1874) Speech sounds and fluent nonsense Impaired comprehension Superior temporal gyrus (BA 42, 44) The main criticisms to the lesion-based neurophysiology is that it studies a re-organized brain. Transcranial Magnetic Stimulation 7

9 TMS Transcranial Magnetic Stimulation Coil TMS can be employed to interfere with and inihibit normal brain function (mm depth and cm radius). On-Off capabilities (comparison with the lesional neurophysiology) Ruohonen J. Background physics for magnetic stimulation. Suppl Clin Neurophysiol ;56:3-12 8

10 Modeling / Grasping and TMS This study aimed at assessing the role of the primary motor cortex (M1) in the control of finger forces in a tripod grasp. To that end, we measured the finger forces evoked by transcranial magnetic stimulation (TMS) of the hand area of M1. Movie 9

11 Grip and Net MEFs 10 5 SU5 4 MEF grip 0 10 SU4 Force (N) 2 0 MEF net Time (ms) MEF Net force smaller than MEF grip MEF grip peaks before MEF Net ( 13 ms) Grip and Net Forces (N) SU3 SU2 SU Time (ms) G. Baud-Bovy, D. Prattichizzo and S. Rossi Effects of transcranial magnetic stimulation of the primary motor cortex on the grip and net forces in the tripod grasp in Proc. World Haptics Conference,

12 Modeling / TMS-EEG Disturbance Rejection EEG TMS TMS-EEG co-registration Disturbance rejection problem 11

13 TMS-EEG Disturbance Rejection Problem Currently amplifiers are turned off during the TMS stymulus We want to get info on a time scale of 1 msec. Disturbance rejection. Signals are not decoupled in the frequency domain. EEG TMS 12

14 TMS-EEG Kalman Filter EEG Model: AR3 e(t) TMS Model: OE331 o OE551 B(z) F(z) + + TMS(t) 13

15 TMS-EEG Kalman Filter EEG Model: AR3 TMS Model: OE331 o OE551 Validation data... 14

16 Outline System Theory and Robotics Neuroscience Modeling (prediction models) Advanced measurement Perception Dissociation Design and VR (Rehabilitation) 15

17 Advanced Measurement Movie Eye Tracking... 16

18 What is Eye Tracking? PC Monitor PC Eye movement data Movie G. Mariottini, D. Prattichizzo, A. Vicino et al. Video-based eye tracking: our experience with advanced stimuli design for eye tracking software in Annals of the New York Academy of Sciences,

19 Quantifying Abnormalities Abnormalities of saccadic movements are frequently the clue to the localization of a disease process. 18

20 Steering Human Attention 19

21 Experimental Protocol Bradley, Mogg & Millar. Covert and overt orienting of attention to emotional faces in anxiety. Cognition and Emotion

22 Concluding Remarks Prediction models (hands. TMS EEG) advanced measurement (eye tracking, haptic) VR for illusion design and rehabilitation (decoupler, grasping) Technology (Life, MRI compatible,...) is an important part How Neuroscience can help Engineering? Perception studies VR design Comments on co-operating with Physicians Experiments are Technology is ready for neuroscience (not yet for surgery). Thanks to G. Mariottini, M de Pascale, A. Formaglio and the students. 21