EFTA01102178.pdf

Epidermal Electronics Science Dae-Hyeong Kim, et al. Science 333, 838 (2011); DOI: 10.1126/science.1206157 II AAAS This copy is for your personal, non-commercial use only. If you wish to distribute this article to others, you can order high-quality copies for your colleagues, clients, or customers by clicking here. Permission to republish or repurpose articles or portions of articles can be obtained by following the guidelines here. The following resources related to this article are available online at www.sciencemag.org (this infomation is current as of August 15, 2011): Downloaded from www.sciencemag.org on August 15. 2011 Updated information and services, including high-resolution figures, can be found in the online version of this article at: http://www.sciencemag.org/content/333/6044/838.full.html Supporting Online Material can be found at: http://www.sciencemag.org/content/suppl/2011/08/10/333.6044.838.DC1.html http://www.sciencemag.org/content/suppl/2011/08/10/333.6044.838.DC2.html A list of selected additional articles on the Science Web sites related to this article can be found at: http://Www.sciencemag.org/content/333/6044/838.full.html#related This article cites 31 articles, 5 of which can be accessed free: http://www.sciencemag.org/content/333/6044/838.full.html#ref-list-1 This article has been cited by 1 articles hosted by HighWire Press; see: http://i.vww.sciencemag.org/content/333/6044/838.full.html#related-urls This article appears in the following subject collections: Materials Science http://i.vww.sciencemag.org/cgi/collection/mat sci Science (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by the American Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. Copyright 2011 by the American Association for the Advancement of Science; all rights reserved. The title Science is a registered trademark of AAAS. EFTA01102178  peeling the device back with a pair of tweezers. When completely removed, the system collapses on itself because of its extreme defonnability Epidermal Electronics and skin-like physical properties, as shown in Fig. I B, bottom (movie SI). The schematic illus- Dae-Hyeong Kim!' Nanshu Litt ' Rui Ma!* Yun-Soung Kim,' Rak-Hwan Kim! tration in the inset shows an approximate cross- Shuodao Wang! Jian Wu,' Sang Min Won,' Hu Tao,` Ahmad Islam,' Ki Jun Yu,' sectional layout. Tae-il Kim,' Raeed Chowdhury, Ming Ying,1 Lizhi Xu,' Ming Li,''` Hyun-Joong Chung' These mechanical characteristics lead to ro- Hohyun Ileum,' Martin McCormick! Ping Liu,s Yong-Wei Zhang,s Fiorenzo G. Omenetto,4 bust adhesion to the skin via van der Waals Yonggang Huang,' Todd Coleman! John A. Rogers't forces alone, without any mechanical fixturing hardware or adhesive tapes. The devices im- We report classes of electronic systems that achieve thicknesses, effective elastic moduli, pose negligible mechanical or mass loading (typ- bending stiffnesses, and areal mass densities matched to the epidermis. Unlike traditional ical total mass of —0.09 g), as is evident from wafer-based technologies, laminating such devices onto the skin leads to conformal contact and the images of Fig. IC, which show the skin de- adequate adhesion based on van der Waals interactions alone, in a manner that is mechanically forming freely and reversibly, without any ap- invisible to the user. We describe systems incorporating electrophysiologicaL temperature, and parent constraints in motion due to the devices. strain sensors, as well as transistors, light-emitting diodes, photodetectors, radio frequency Electronics in this form can even be integrated Downloaded from www.sciencemag.org on August 15, 2011 inductors, capacitors, oscillators, and rectifying diodes. Solar cells and wireless coils provide directly with commercial temporary transfer tat- options for power supply. We used this type of technology to measure electrical activity produced toos as a substrate alternative to polyester or by the heart, brain, and skeletal muscles and show that the resulting data contain sufficient PVA. The result, shown in Fig. ID. is of possible information for an unusual type of computer game controller. interest as a way to conceal the active compo- nents and to exploit low-cost materials (the gib- hysiological measurement and stimula- "skin-like" membranes that confomrally lam- strate, adhesives, and backing layers) already p tion techniques that exploit interfaces to the skin have been of interest for more than 80 years% beginning in 1929 with electro- inate onto the surface of the skin by soft contact, in a manner that is mechanically invisible to the user, much like a temporary transfer tattoo. developed for temporary transfer tattoos (movie SI). Potential uses include physiological sta- tus monitoring, wound measurement/tmatment, encephalography from the scalp (1-3). Nearly Materials, mechanics, and design strategies. biological/chemical sensing, human-machine in- all associated device technologies continue, how- A demonstrative platform is shown in Fig. I. terfaces, covert communications, and others. ever, to rely on conceptually old designs. Typical- integrating a collection of multifunctional sen- Understanding the mechanics of this kind of ly, small numbers of bulk electrodes are mounted sors (such as temperature. strain, and elect:0- device, the mechanophysiology of the skin, and on the Ain via adhesive tapes, mechanical clamps physiological), microscale light-emitting diodes the behavior of the coupled abiotic-biotic system or straps, or penetrating needles, often medi- (LEDs), active/passive circuit elements (such as are all important For present purposes, the skin ated by conductive gels, with terminal connec- transistors, diodes, and resistors), wireless power can be approximated as a bilayer, consisting of tions to separate boxes that house collections of coils, and devices for radio frequency (RF) com- the epidermis (modulus, 140 to 600 kPa; thick- rigid circuit boards. power supplies, and com- munications (such as high-frequency inductors, ness, 0.05 to 1.5 mm) and the dennis (modulus, munication components (4-9). These systems capacitors, oscillators, and antennae). all integrated 2 to 80 kPa; thickness, 0.3 to 3 mm) (20-23). have many important capabilities, but they are on the surface of a thin (-30 gm). gas-permeable This bilayer exhibits linear elastic response to poorly suited for practical application outside of elastomeric sheet based on a modified polyester tensile strains 5.15%, which transitions to non- research labs or clinical settings because of dif- (BASF, Ludwigshafet Germany) with low Young's linear behavior at higher strains, with adverse, ficulties in establishing long-lived, robust elec- modulus (-60 kPa) (fig. SI A). The devices and irreversible effects beyond 30% (24). The sur- trical contacts that do not irritate the skin and in interconnects exploit ultrathin layouts (<7 pm), face of the skin has wrinkles, creases, and pits achieving integrated systems with overall sizes, neutral mechanical plane configurations, and op- with amplitudes and feature sizes of 15 to 100 pm weights. and shapes that do not cause discom- timized geometrical designs. The active elements (25) and 40 to 1000 pm (26). respectively. The fort during prolonged use (8, 9). We introduce a use established electronic materials, such as sil- devices described here (Fig. I) have moduli, thick- different approach. in which the electrodes, elec- icon and gallium arsenide, in the form of fila- nesses, and other physical properties that are well tronics. sensors, power supply, and conununi- mentary serpentine nanoribbons and micro- and matched to the epidermis. with the ability to cation components are configured together into nanomembranes. The resuh is a high-performance conform to the relief on its surface. We therefore ultrathin, low-modulus, lightweight, stretchable system that offers reversible, elastic responses to refer to this class of technology as an "epidermal large strain deformations with effective moduli electronic system" (EES). (<150 kPa), bending stiffnesses (<1 nN m), and Macroscopically, an EES on skin can be 'Department of Materials Science and Engineering. Beckman areal mass densities (<3.8 mg/cm2) that are or- treated as a thin film on an epidermis-dennis Institute for Advanced Science and Technology, and Frederick Seitz Materials Research Laboratory, University of Illinois at ders of magnitude smaller than those possible bilayer substrate. Microscopically. the sizes of the Urbana-Champaign, Urbana. IL 61801, USA. 'Department with conventional electronics or even with re- individual electronic components and intercon- of Electrical and Computer Engineering, Coorcinated Science cently explored flexible/stmtchabk device tech- nects are comparable with those of relief features Laboratory, University of dines at Urbana.Champaign, Urbana, nologies (10-19). Water-soluble polymer sheets on the skin and therefore must be considered IL 61801, USA. 3Department of likchanical Engineering and [polyvinyl alcohol (PVA) (Aicello, Toyohashi, explicitly. We began by considering aspects of Department of OW and Environmental Engineering, North- western University. Evanston, IL 60208. USA. `Department of Japan); Young's modulus, -1.9 GPa; thickness, adhesion, in the macroscopic limit. Globally. de- Biome:kcal Engineering, Tufts Unhers*y, Ilsdford. MA 02155, -50 µm (fig. SIB)] serve as temporary supports tachment can occur in either tension or compres- USA. 'Institute of High Performance Computing. 1Fuslonopotis for manual mounting of these systems on the sion becaum of interfacial cracks that initiate at Way, 016.16 Connexis. 138632, Singapore. EStace Key Lab- skin in an overall construct that is directly anal- the edges or the central regions of the EES. re- oratory of Structural Analysis for Industrial Equipment Dalian University of Technology, Dalian 116024, China. ogous to that of a temporary transfer tattoo. The spectively. Low effective moduli and small thick- image in Fig. 1B. top, is ofa device similar to the nesses minimize the deformation-induced stored 'These authors contributed equally to this work. tTo whom correspondence should be addressed. E•mait one in Fig. IA, after mounting it onto the skin elastic energy that drives both of these failure jrogers@uiuc.edu by washing away the PVA and then partially modes. Analytical calculation (27) shows that 838 12 AUGUST 2011 VOL 333 SCIENCE www.sciencemag.org EFTA01102179  RESEARCH ARTICLES' compared with silicon chips (thickness of —1 min) the other 145 kPa (30:1) (fig. SIC). The results, overall range of defonnability can be optimized and sheets of polyimide (thickness of —75 pm), the both theory and experiment, confirm that reduc- in systems composed of active devices joined driving forces for delamination of the EES/skin ing the modulus and thickness lowers the driv- together in open-mesh Am-tures by non-coplanar interface are reduced by more than seven and ing forces for interface delamination for a given interconnects in neutral mechanical plane con- four orders of magnitude. respectively. Measure- applied strain (bending or stretching) without figurations, in which elastomers with relative- ments and theoretical calculations (27) shown in lower bound. ly large moduli (2 to 10 MPa) and thicknesses Fig. 2A explore the relevant scaling behaviors in The mechanical properties of the EES de- (millimeters to centimeters) serve as substrates structurts that provide simplified, macroscopic pend on the effective modulus and thickness of (13, 14). For EES, the effective modulus (EEEs) models of EES/skin. The experiments use sheets both the circuits and sensors and the substrate. and bending stiffness (E/F.F.$), rather than the of polyester (-2 mm thick) for the skin and fihns In samples such as those in Fig. 1, the properties range of stretchability. are paramount These It- ofpoly(dimethylsikocane) (PDMS) (Dow Coming, of the active components and interconnects can quiretww. demand alternative designs and chokes Midland, USA) for the EES. The critical delam- dominate the mechanics of the overall system. of materials. If we assume that the effective ination strain is plotted in Fig. 2A as a function The in-plane layouts and materials of this layer moduli of the individual devices (for example, of PDMS thickness for two different formula- are therefore key design parameters. Recent work Young's modulus -160 GPa for Si and —90 GPa tions: one with a modulus of 19 kPa (50:1) and in stretchable electronics establishes that the for GaAs) are much higher than those of the antenna LED stria n an' temp. sensor 0.5mm mm encemag.org on August 15, 2011 attached to skin !ter partially detach from the skin 3mrrt PI — 4- device 7lint crumpled P • circuit t PE 301m 4— polyester (-50 Kea) Downloaded from www. 4 doss power coil RF coil RF diode ECG/EMG sensor after fully detach from the akin C 0.5cm .,„. ii err g11W neat. ler undeformed state D loctronics backside of tattoo after transfer —to after Integration onto skin - to after deformation Fig. 1. (A) mage of a demonstration platform for multifunctional elec- ture, with the neutral mechanical plane (NMP) defined by a red dashed line. tronics with physical properties matched to the epidermis. Mounting this (C) Multifunctional EES on skin: undeformed (left), compressed (middle), and device on a sacrificial, water-soluble film of PVA, placing the entire structure stretched (right). (D) A commercial temporary transfer tattoo provides an against the skin, with electronics facing down, and then dissolving the PVA alternative to polyester/PVA for the substrate; in this case, the system in- leaves the device conformally attached to the skin through van der Waals cludes an adhesive to improve bonding to the skin. Images are of the back- forces alone, in a format that imposes negligible mass or mechanical loading side of a tattoo (far left), electronics integrated onto this surface (middle left), effects on the skin. (B) ES partially (top) and fully (bottom) peeled away and attached to skin with electronics facing down in undeformed (middle from the skin. (Inset) A representative cross-sectional illustration of the struc- right) and compressed (far right) states. www.sciencemag.org SCIENCE VOL 333 12 AUGUST 2011 839 EFTA01102180 I RESEARCH ARTICLES interconnects and that the interconnected device (Fig. 213, right) indicate that such FS-EES sam- mechanics (fig. SIG). In both options, suitable components (rather than the substrate) dominate ples (Fig. 213, left) achieve EE (-140 kPa) and designs lead to mechanical and adhesive prop- the mechanics. then we can write the approxi- Elms (-03 Witt) (27) that are comparable with erties that allow conformal adhesion to the skin mate expression ELEN En (I + Las), where the epidermis and more than one and five orders and minimal loading effects (Fig. 2C). Without E,„, is the effective modulus of the intercon- of magnitude smaller than previously reported optimized layouts, we observed delamination un- nects, Ld is the characteristic device size, and L, stretchable electronic devices, respectively (28). der similar conditions of deformation (fig. Sill), is the distance between devices, as illustrated in Furthermore, highly repeatable loading and un- which is consistent with the fracture modes il- fig SID. The value of EF.Es can be minimized loading stress-strain curves up to strains of 30% lustrated in Fig. 2A. by reducing E1,,, and L/L... For the former. thin demonstrate purely elastic nsponses, with max- For many uses of EES, physical coupling of narrow interconnect lines formed into large- imum principal swains in the metals that are less devices to the surface of the skin is important. amplitude "filamentary serpentine" (FS) shapes than -0.2% (fig. SIE). Calculations yield effec- Confocul micrographs of EES mounted on pig represent effective designs. For the latter, ultrathin tive tensile moduli (Fig. 2B, right). with excellent skin appear in Fig. 2. D and E, as well as fig. 52C active devices that adopt similar FS layouts and correspondence to experiment Such FS layouts Wye information and bare pig skin confocal mi- continuously integrate with FS interconnects can maintain nearly 20% weal contact of active crographs am S110 \411 in fig. S2. A and B. respec- reduce the effective value of Ld to zero. The elements with the skin, for effective electrical in- tively; sample preparation and imaging procedures value of E.1as decreases rapidly with the thick- terfaces. In certain applications, layouts that in- can be found in (27)]. With Fs structures, the nesses of the devices, interconnects, and sub- volve some combination of Fs geometries and results show remarkably conformal contact, not strate. An ultrathin FS construct is shown in Fig. device islands (Ld not equal to zero) connected only at the polyester regions of the EES but also Downloaded from www.sciencemag.org on August 15, 2011 2B. left, with a cross-sectional schematic illus- by FS interconnects (Fig. I and fig. SIF) can be at the Fs elements (Fig. 2, 13 and E). Similar tration as an inset. Results of tensile testing used, with expected consequences on the local behavior was obtained, but in a less ideal e 60 —•— 50:1 x 60 D —* c 30:1 40 60 co 4'20 theory - Fe ! it° a. 0.• IP • -roe 0 020 0 0 0 3 0.6 0.9 1.2 1 5 O 0 0 0.5 1.0 1.5 2.0 PDMS thickness (mm) PDMS thickness (mm) 90 ter 9.20 0 230 N 0 0 5 10 15 20 25 30 Strain c9.) E device 5kin • Fig. 2. (A) Plots of critical tensile (left) and compressive (right) strains for delamination of a test structure consisting of films of PDMS on substrates of polyester, designed to model the EES/skin system. Data for formulations of PDMS with two different moduli are shown (red, 19 kPa; blue, 145 kPa). The critical strains increase as the PDMS thickness and modulus decrease, which is consistent with modeling results (Ones). (B) Optical micrograph of an EES with FS design OK The plot (right) shows the stress-strain data from uniaxial tensile measurements for two orthogonal directions. Data collected from a sample of pig skin are also presented. The dotted lines correspond to calculations performed with finite element modeling. (C) Skin of the forehead before (top left) and after the mounting of a representative FS-EES, at various magnifications and states of deformation. The dashed blue boxes at right highlight the outer boundary of the device. The red arrows indicate the direction of compressive strains generated by a contraction of facial muscles. The red dashed box at the top right corresponds to the field of view of the image in the bottom left. (D) Confocal microscope image (top view) at the vicinity of the contacting interface between an FS-EES laminated on a sample of pig skin. The FS structure and the skin are dyed with red and blue fiuorophores, respectively. (E) Cross-sectional confocal images at locations corresponding to the numbered, white dashed lines shown in the top-view frame above. 840 12 AUGUST 2011 VOL 333 SCIENCE www.sciencemag.org EFTA01102181  RESEARCH ARTICLES' fashion (fig. S2C), with layouts that incorporate 3A; the inset shows an analogous design based motion of the sleinthiofluids) (Fig. 3D, left, and device islands. These observations are consistent on a rectangular device island and FS intercon- fig. S3, E to G), and silicon FS photovohaic cells with analytical mechanics treatments that use nects) via contact with the skin in a common- (Fig. 3D, right). Such cells can generate a few tens macroscopic models of the EES and account for source amplifier configuration (Fig. 3B, left). The of miaowatts (fig. SRI); increasing the a=s or microscopic structures on the skin (27). Related measured frequency response at different input weal coverages can improve the output but not calculations suggest that spontaneous pressures capacitances (CIN) is indicated in Fig. 3B, right, without compromises in size and mechanics. Wire- created by surface interactions are -ID kPa (fig. and is in quantitative agreement with circuit sim- less powering via inductive effects represents an SIOB), which is below the sensitivity of human ulations (fig. S3, A and B). The value of CIN is appealing alternative. An example of an FS induc- skin (-20 kPa) (29) but still sufficient to offer determined by a series combination of capaci- tive coil connected to a microscale InGaN LED reasonable adhesion. Microscopic models indi- tances of the gate electrode, the encapsulating is shown in Fig, 1E. with electromagnetic model- cate that these interactions generate compressive PI, and junction between the gate electrode and ing of its RF response. The resonance frequency forces (per unit length) of —0.1 Wm for each the body surface. The bandwidth matches re- (-35 MHz) matches that of a separately located FS strip (27). Improved bonding can be achieved quirements for high-performance EP recording. transmission coil powered by an external supply. by using adhesives that are built into platforms A typical layout for this purpose includes four am- Voltage and cumin outputs in the receiver are mrf- for temporary transfer tattoos, as in Fig. I D. plified channels, each comprising a FS-MOSFET, &lent to operate the microscale LEDs remotely. Multifundional operation. A key capability of a silicon-based FS resistor, and an FS electrode. as shown in Fig. 3E. Such coils provide power EES is in monitoring electrophysiological (EP) One channel provides a reference, whereas the directly in this example; they can also conceivably processes related to activity of the brain (elecuoen- others serve as sites for measurement. Results of be configured to charge future classes of EES- Downloaded from www.sciencemag.org on August 15, 2011 cephalograms (EEGs)], the heart [electrocanlio- demonstration experiments appear subsequently. integrated storage capacitors or batteries. grams (ECCrs)] and muscle tissue [electroinyograins Many other classes of semiconductor devices Examples of various RF components of the (EMGs)J. Amplified sensor electrodes that in- and sensors are also possible in EES, including type needed for wireless communications or for corporate silicon metal oxide semiconductor field resistance-based temperature sensors built with scavenging RF energy are presented in Fig. 3, F effect transistors (MOSFETs) in circuits in which meander electrodes of Pt (Fig. 3C, left, and fig. and G. Shown in Fig. 3F is an optical image of all components adopt FS designs provide de- S3C), in-plane strain gauges based on carbon- silicon PIN diode (left) and its mall-signal scat- vices for this purpose. Here, the gate of a FS- black-doped silicones (Fig. 3C, right, and fig. tering parameters (fig S3K), indicating insertion MOSFET connects to an extended FS electrode S3D), LEDs and photodetectors based on loss (S21 in forward condition) of <6 dB and for efficient coupling to the body potential (Fig. AlInCraP (for possible use in optical dietetic& isolation (S2 I in reverse condition) of >15 dB A D C X01 R ',We - it detector • B 1.6 E F 2mm 1.2 0.8 0.4 1 — 1mm l\AW-1\i 0.0 • 10•3 104 10' 10' 10' Frequency (Hz) • G N 0.9 LI 0.8 6-0.7 O u- 0.6 Ti 0.5 8 0.4 ti 05 1.0 1.6 2.0 2.6 30 Capacitance (pF) Fig. 3. (A) Optical micrographs of an active eledrophysiological (EP) sensor and a strain gauge that uses electrical y conductive silicone (CPDMS; right). (D) with local amplification, as part of an FS-EES. (Left) The source, drain, and gate Image of an array of microscale AlInGaP LEDs and photodetectors, in an in- of a silicon MOSFET and a silicon feedback resistor before connection to sensor terconnected array integrated on skin, under compressive deformation Deft) electrodes, all in FS layouts. (Inset) Similar device with island design. (Right) and of a FS silicon solar cell bight). (0 Image of a FS Wireless coil connected to The final device, after metallization for the interconnects and sensor electrodes, a microscale InGaN LED, powered by inductive coupling to a separate trans- with magnified view (inset). (B) Circuit diagram for the amplified EP sensor mission coil (not in the field of view). (F) Optical micrograph of a silicon RF shown above (left). (Right) Measured and simulated frequency response for diode. (G) Optical micrograph of an interconnected pair of FS inductors and different input capacitance = co, 1,uF, 220p0. (C) Optical micrograph of a capacitors designed for RF operation Deft). The graph at right shows resonant temperature sensor that uses a platinum resistor with FS interconnects Deft) frequencies for LC oscillators built with different FS capacitors. www.sciencemag.org SCIENCE VOL 333 12 AUGUST 2011 841 EFTA01102182 I RESEARCH ARTICLES for frequencies of up to 2 Gliz. Examples of Systems for electrophysiological recording. high-quality signals with information on all FS inductors and capacitors and their RF re- EES configured for measuring ECG, EMG, and phases of the heartbeat, including rapid depo- sponses appear in Fig. 3G and fig. S3L. Con- EEG in conformal, skin-mounted modes with- larization of the cardiac wave, and the asso- necting pairs of such devices yields oscillators out conductive gels or penetrating needles pro- ciated QRS complex (Fig. 4A, right) (32). EMG with expected resonant frequencies (Fig. 3G, vide imponant, system-level demonstrations (fig. measured on the leg (27) with muscle contrac- right). A notable behavior is that the response S4A and movie S2) (27). All materials that tions to simulate walking and resting are pre- varies with the state of deformation because come into direct contact with the skin (Au, PI, sented in Fig. 4B, left. The measurements agree of the dependence of the RF inductance on geo- and polyester) are biocompatible (30, 31). Mea- remarkably well with signals simultaneously metry. For example, at tensile strains of —12% surements involved continuous use for as many collected using commercial. bulk tin electrodes the resonance frequency shifts by -30°4(4. S3, as 6 hours. Devices wom for up to 24 hours or that require conductive gels, mounted with tapes I and 5). Such effects, which also appear in the more on the arm, neck, forehead, cheek, and chin at the same location (Fig. 4B, right, and fig. wireless power coils but not in the other devices showed no degradation or irritation to the skin S4B, right). An alternative way to view the data of Fig. 3, will influence the behavior of antenna (figs. 514 and S15). Devices mounted in chal- (spectrogram) is shown in Fig. 4C, in which the structures and certain related RF components. lenging areas such as the elbow fractured and/or spectral content appears in a color contour plot These issues must be considered explicitly in debonded under full-range motion (fig. S16). with frequency and time along the y and .r axes, EES design and modes of operation. ECG recordings from the chest (27) revealed respectively. Each muscle contraction comsponds D Downloaded from www.sciencemag.org on August 15, 2011 A 52- 200 , ▪ 200 260 up down left right 100 • 100 200 base Ira ra. ti 0 ;150 V S -100 • 100 5 10 15 00 0.2 0.4 Time (s) Time (s) .100 B 5. 100 &thy 100 cony. LL d Erit 1014 filltyolorn 150 ci 0 0 E 10 <-100 100 0 t 2 3 0 1 2 30 1 2 30 1 2 3 5 10 15 20 0 5 10 15 20 Tima (s) Time(s) Times) Time(s) Time (s) Time (s) C -r7r E up 17IIIDIG113, right = 200 active walk stand •Ila• ICE IS • ■ •I. U • • •••• • • ESN Mina (1) 100 ■ • ••_J X ■ ME III • .4 Min • 10 Mtn I III LEL 0 5 10 15 20 N passive down left X 200 walk MERE stand smile* U akiN ■ ■ • IMRE •w 100 ir non ti •,:•• WIN ••••••• • MS • ••••••• • cr 4 • r. ti os 1 at • ", ■ moist • ■ E 0 Men "U U- 5 10 15 20 NINE ,103 Time(s) F _ 31:1 eyes closed eyes open 20 /10 alpha rhythm Opening blinking • 0 810