Electroencephalography (EEG)

http://ese.wustl.edu/~nehorai/eegmeg/eeg2.jpg, http://www.gtec.at/service/images/10_20_system_mod.gif

http://www.electropsychology.com/valovi.gif, http://en.wikipedia.org/wiki/Electroencephalography

8-12 Hz (awake, but relaxed, attenuated w/ activity)

mu alpha having to do w/ motion

12-30 Hz (Low amplitude w/ multiple/varying freq when thinking)

up to 3 Hz (sleep and babies)

4-7 Hz (kids and meditation)

26-100 Hz

raw EEG

http://www.sciencephoto.com/media/229176/enlarge

http://www.wtec.org/bci/welcome.html

Wolpaw, PNAS 101(51), 2004, 17849-17854

Fig. 1

C3=L C4=R

nose

(24 Hz)

(12 Hz)

Wolpaw, PNAS 101(51), 2004, 17849-17854

Fig. 1

beta mu (alpha)

C3=L C4=R

nose

3&42&51&67&8

1&23&84&75&6

C3 C4

Wolpaw, PNAS 101(51), 2004, 17849-17854

Table 1

• http://www.pnas.org/content/suppl/2004/12/07/0403504101.DC1/03504Movie1.mov

Movie 1. Two-dimensional cursor control with scalp-recorded sensorimotor rhythms. In this QUICKTIME movie, a person with spinal cord injury (i.e., user A) uses scalp-recorded sensorimotor rhythms to control cursor movement in two dimensions. In each trial, a target appears at one of eight possible locations on the periphery of the screen, and 1 sec later, the cursor appears in the center and moves. Its vertical movement is controlled by the sum of the weighted amplitudes of a 24-Hz beta rhythm recorded from the scalp over left and right sensorimotor cortices, and its horizontal movement is controlled by the difference between the weighted amplitudes of a 12-Hz mu rhythm recorded over left and right sensorimotor cortices, as described in Methods.

Wolpaw, PNAS 101(51), 2004, 17849-17854

Fig. 2

Wolpaw, PNAS 101(51), 2004, 17849-17854

Fig. 3

Wolpaw, PNAS 101(51), 2004, 17849-17854

Fig. 4

Looking into the future….

http://www.londonyogi.com/images/spine.jpg

They use more channels and more frequencies….and tailor it for different users

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 1

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 2

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 2

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 3

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 3

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 4

• Not the original video… but close• http://

www.veoh.com/watch/v17476140kmJjEhTs

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 5

Hochberg, et al. Neuronal ensemble control of prosthetic devices by a human with tetraplegia, Nature, 44(13), 2006 p164-171.

Fig. 6