c .31 l@-7 6 Dear As a result of our discussions on 21 August 1973, I am propos- in- a three phase pro-r,,im desi-ned to: Establish the effectiveness of electric fish in d@--tectinc, 2 forei-n objects at a distance; Determine the methods used by electric fish for rancring and location; and (3) Desion equipment systems suitable for replacing electric I-V fish in terms of targetincy foreian objects. I am enclosing -. summary of this program. Phase I of the procrram 2describc-d herein will correspond to "Phase II" of the program described I however the tasks have been modified somewhat to better serve the needs of the pro-ram. The remainder of the present contract v.,,ill be used to assess necessary parameters of the electroreceptors system in Gymnarchus and Gn2thonemus. Both of these fishes would be used in the Phase I and Phase II of the 2program recom- mended above. I am also enclosincr a more detailed description of the experl- ments to be performed in Phase I of the proposed procram ard an example of the type of exderiments that are appropriate in Phase III. Details on Phase H would depend strono-ly on the results of the Phase I investigation. I hope that this proposal meets with your approval3. Please let me know if you can recommend any added experiments or studies which would aid in the development of a prototype hardware system. With best wishes., A PROPOSED THREE PHASE PROGRAM TO DEFINE HARDWARE ANALOGUES OF ELECTRIC FISH SENSOR SYSTEM PHASE I IF 9 ESTIIMA nNG THE EFFECTIVENESS OF ELECTRIC FISH IN DETECTING FOREIGN OBJECTS AT A DISTANCE Perform psycliopliysiolo-ical experiments using different kinds of electric fish in restricted water so as to estimate their ability to identify the existence of forei-n o2bjects in this water takin- into account electrical discontinuities imposed by the boundaries of that water and the forei,-n objects placed within it. Specifically, consider the fish as a sio@nal generator and receptor and the use of auxiliary sic,,nals which replicate the fish's sicrnals and other signals of specific interest. Com- 2 pute the e.-. ected behavior of such fish in open ocean or fresh ivaters p given typical boundary con,,Iitions v,--&th respect to depth, tol)olocr , in-. c,Y homo-eneity of the water, temperature, and other applicable parameters. 2 Summarize these findincrs in terms of the ability of these fish to identify foreign objects in a harbor or other natural body of water of interest. . foreic7n objects such as small submarines, torpedoes, scuba divers, skin divers, mines, and others. More explicitly, d--termire the sensory capability of individual electric fish in2 terms of their ability to sense the existence of foreicn objects as a function of rancre, fundamental area, volumetric displace- ment, diff erential discontinuity, and so forth. In this regard, use a tank of water at measured temperature and electrolytic conditionts. Retain a fish near one point and insert in the water various objects, discernin(r 2 the different behavior of the fish as these objects are inserted by con- currently monitoring. the electrical field within the v,7ater. Specific levels of background noise will be introduce-.' by usina, a noise generator and measuri.nc,T the noise amplitude in the tank. Experiments will be per- formed under normal aiid extreme noise condit2ions. From these results, calculate the estimated behavior of such a fish in detectinm an object in an infinite v.,ater domain and lar-e scale w,.iters with various boundary conditions. PHASEII DETERMINING THE METHODS USED BY ELECTRIC FISH FOR RANGING AND LOCATION Perform detailed experiments 2wherein the particular character- istics of electric fish are related to their abilities with respect to ranoino, and location. Particular attention will be focused upon the use of phased arrays of receptors, the fish's ability to determine incremental time lar's in the si,.-nal, the estimated sl)--I-tral prope.-ties of the sirral, the fish's 2 ability to modify the transmitted sianal as a reflection of knowledae gained from previous receptions, and so forth. Interpret these findincrs in terms O.L specific schematics and data analysis required to synthesize models of the fish's capability, models v@,,hich when reified would provide sianal- advantage over the state of the artwith respect to such a target as described 2 above. PHASEIH DESIGN OF EQUIPMENT SYSTEMS SUITABLE FOR REPLICATING ELECTRIC FISH IN TERAIS OF TARGETING FOREIGN OBJECTS Desio-n, fabricate and test experimental apparatus suitable for replicatincr the above-referenced models. Perform experiments ,a7ith 4 this apparatus so as to improve its ability in various recrards. Make a specific comparison of this capability to that of an electric fish and estimate the utility of such an apparatus in terms of operational situations. 2 ---------- COST ESTIAIATE PHASE I $ 6 months PHASE II - $ 5 1 year PHASE III - $ 1 year 3 _,o 11@A7ES7'T I'l.'17L':, L l' LG.,"$TION OF ELE%rl"J.'j-@j@ FISTT .LiES.Iii-I'D QUESri'loi@1-02- VRIICII ST-LLL IN Electric fislie,-, liave -cpcci.-ilizcc'4 clectric oi,L-,,",ns: (1) tr4-ii--mittiliff or-,,,.iis Y.,hicli traii,-@,,-nit electric si-ii-,-Is niodul,,,-tecl ,ii-id co,2@led in specific -,,.rt o'L the 1,,atcr and (2) re,@-eiviiir, oi,,,,,,,,ns (clectrorcccptors) -r.?Iiieh ,,re p -,i 1 i s L@, 11 2 systeni -,,.)d cILtect ci-tlior (.-i) di.:@.c:oiik'iiiujtje.-, in the electric fielet, gellerp.,,.-Od b37 the -v.,hei-A tli,,@ fislic,-- -i-,se ,tr. -cti-%,e C!L",cc2,-io,,, 0.)) Z.!, C. L t. c]iL-.zi,-c-s iii the elec,,,',L,ic fi(-,Id -.-iicr,.,',cd tie aLitiorlil-,,thmic ,when tlic- fis'jies us-- ,i pas,.2-ive de te,,--tiii<,r bys4Lejii and (c) electrical -i",ii;,.Is emitted by fisho.-I o-.Le the same --pecies o-,- ol' other species, even r.-onelectric fi@,'Ii N,.?hicli .-till produce an electric field re--ultipc,:r, froin their niuscu'Lar activ:; duri,nr, sv,.,imriin-. All this '#.-hat el.(ic'Lric fishes can naiiig-"te, detect, loc,,i'Le and. identify liviiiy or iioiiorg,,inic m,,i'Lter -.,.iid car. co.-nmui)icate under- water by o-lp electric si<,,,ra7,s and/or electrom(-,,,,Tnetic d--tect,.on. The elo,ctric po-,.,?er ilivol-ved is very sir,,-Il. Some of the electric fishes have biiilt-in a jariiiiir.,,, ,ivoid,-Lnee sys"Lem. Mo@@.,t of them can extr2Ct C-4 sirrnal fro-. 2 a iiolse tliall is than the signal itsel-Le. and from ti@e da'Lawe have from other scient- is'Ls Y,,e conc.Luded tli-"t uriciuc methods of detecti-oii and corimunic,"-tio,,i are pecul-Lar to some electric fi-sh-2-s, which.could sirrllificaiitly improve our te%-.Iinolo@-y if properly applied. li-i tlic- app--nctices to this chapter I sumriarized the results of the research I h2.vc dc,.ii,,- so far oi,. electric Iish,,.,s 4 4 n C d ::,Csh v.,a-:cr a.-.cl c-'Lectric L' .shcs were -,1,4 5-:', -r -.- C .:7@'C -CS. co!'--cc-.c& da4.a c--ca-l.terec! #' h r O,,: - @'- -a-a,-,4-as ,t-e -'cw ---pters O-- -r4c '4-'@,cs --@nd data '.-orr, our ow- 2 boo',.cs havir.... S O @,,n e c.1 4. clec4i. of ma-is '#.h..,-Ar hab@.6ats. C.1:5eLs2os O@. a C C 1 -a s-ud'ed. Wc. -&"Ou,-.d a C S A,.es we 11 C', Y 6 (a cancer-type of skin disease). 2 -..a an, a@6o:ny O-.' e'-ec-.r-.C 0:-@,-ZLnS 0-.@' e C " r 0 7-,A-.Dr-,:S, M-al-an-Lcru,-us, a n,-@ studied. 2 carapo was Eos,n ard o-.@' 'L,A-.e e.-ec-.rorece-r;t.ors O c C Z' O 7-,.@-. 3 Z- IL. S C wa@-a -:-2.d electricus, carapo, Sklernarclius ,tlbifrons, Eicrenmannia troscheli, petersii, Gnatlioiiemus curvirostris, Gvmnarchus niloticus by E. 2 electricus. -ectr L 'ere. -he -oceacii,-,2gs c-@' -;6-.-.e Roc@.ies'uer Co:-.-@ --@ce on D-T@-.a ir, X. Ensie@'.n -.,'-'.-ess, 1965. e2=e.-:6.-ren@@.s we.-c t)er.-L"o.-r.-.ed wi,6-h St.er,-.a.-c.-.Us albifrons, electricus, and Gymnarchus ri'llot@icu@s. 7. was b.-our,@.t about '6,'L-.e 2 of elec'6ric -i"ishes. 1; sers@.'.-.vity 'Lo elec4-.-,Ac ard -L.a,-;ne@L'Lc s'.,.mul.i was c.-.ec'A-ed. x a c e a S r c z.-i e .- c i-:i c O2.;' -L 1 i a d - c c h - e; c v S were 'L@-CLCC- -Or t,-.a L-LICCt.-C,7-,.-.OrUS t','ic vo"ate, peak t)o%-,,er, ard %A L - I 2 L 4.= av,-"rz-e :@ov%,e- O:' -@s Curves w-,re tl-aced al.soe-'Or vo'A.4-.a,-, a A L6 4 L :-, S @u le:,,-'Lh OA' A",-Ls,2ties ard of 9. wc-,.-c cerA-'o.-rned, a,-d the c-.f-L'cct of do cu,-z-cnts on t.@-Ae c.if-.,nals of c'..cctr;.c f;.sies lias b.:@c:n 1 -.'O:- Elcczropho.-us, G,,7nrarci-lL;s, Gn.--'.nonc.-.nus, ard 0, C.-,a,-igcs 1-6 L: r 0 O rcquc,-,cy C).- A.IC 2 1-c c c by .1c:cf r, w a s ,.v c! S, i 1 3 o 2 8 curves -4.raced :'O.- @Llc,.-.z2-@-a@-,;rcs o-@ b,@-c.4 - O' S, er;-,.%,.-c'iius was. i.-iVOS cr,-,;-t@.ed by f;.sh were s@,ud:.ed. T.'-'Ac 2 e-&'@ec-@. a+. low '6-c.-,..ncr:L'6u.-es o.-@: the water o.,-i albifrons'was studied. pieser,,,ed at the AAAS U.-,'@vers;.@Ly oL2' Cal;..L'O,-,-,:La in co-"-6z,".Ior W;@-'- Di-. 'as'ow, Ur.:Vc-@-5, y ol -.awa:i. Oii,y 4-- e co,-id,,:c4-.er-l i,6-4 our 'Labora2@,oz-y are =.en,'ioicd -iere. Dr. M. c c n d c -. a -@ c - a r a r @a s O:'. y.-':. Z a -@ c! 0 @'- a s i a z',- e @.A .4 '--'awai2i, h.-Ls resu.,@@.s are I-,resc,-i"ed as first par@6 o Ar 'L- he pi-ese.-.ze- 2'0 "L S :v ,=J A Ly-z o' .'A les:ls a-o-a- way o-:' 2 a el,:-c ric -shcs .,.,o-k Z. v - C a 0 -.D C.- L@:r. Z a a -7,:: V: a @o 6 @j LA' A IIA 0":--.- Ole 2 CC. Gyninarchus niloticus is sensitive to a z. d o a';@ o u. 0 . ?.;,v S t e r n a r c h u s a lb i f r o n s i s on,'@.y as s c-2.-. s;. v e . -s o,. so,-.ne previous e.,.@-pe-L-ner,'6s were i v e n l,ii.-h dc sa,-.si@'ziv:zy. ;..n te--s 2was -iven of exper-Lrnen+ls in w.'-.:Lc!-i 1. niloticus and Sternarchus albifrons were trained to s@ for 'L-he 0.@: 0-b-;ects by elec'.ric "ic azle Z, av @aw ad., T@6 ;.s co-c',--ded o-@ a c.-,&.. z..,L c.-@.-.pcr-. 2 t -L- niloticus can detect objects by the disturbance of its o w.-i a'. a c z c -,@',-6e.d in ti-.a wa'#-.er. :7. Z. rk, S C: C r -., V.F-,. 0:,. 0e a r, P r c, x zn a a e o y 0 S ia 14-lod 0..&:, c,'@,4jec,. o c a o,-, is shown. The of the receptors of the pertu@-b;.n,- field c',.ue -o-s. in 40 zn 0,.2)jcct depe,-,ds on the elec4-rical oro-c-:-+..4kes of ',!-.e recez4, cases, o--' #'he .-ecop-,,oz-s is to A;.-he no-.en@-.,-al or '6o ;.+.s second cle.-,Lva@6i-ve. G.-alohs are ctiven showing. '#.he of a.-i objc@cl., on '6',",,e potert,,al and on .k-,s seco,,-,d cleri-val,-,i-ve -e sur@ace of the f,.'sh. 18. E.%-periments are described usin- Gymii,,irchus niloticus which (.,L) con- z@- firm that the mechanism of object location e ploys the detection of the distortion of the electric field produced by discontinuities in this fie2ld, and (b) indicate the limits of the sensitivity of the fish. 19. The detection of the second derivative mode of its own emitted signals appears to be the most probable one operating in Gymnarclius. The ex- perimentally determined limits of detection are di@-sc@usse@in@relation to the random noise in the recepl.-ors circuit. It is concluded that both spatial and temporal inte-ration are likely to be employed. "or res-,onse lo d4-e-t curre.-.'s 2 'y --ors a-e -orc@a 6 Z,Z'a A.Z !S CO-IC'I;-Iad S recep 2 c, 3 ",.-A c a S e S e.- -n-i e s e r e dev:se-' @o @@-:,.d 4hc O: o -,he o,-.es e n-@:1. z -. e ci by e-eczrc f@ c-es n u,-iderwa@er 2 -OVCC. a- a.-: i- .S Cicse @o t,',c der-'@vaLive o-@ I.-I case we cal-I 2 S y S c@ n-, t c L c r a ia S a c O.-, c..-, rn 7:; a v e,-. c-@' '10:' a znt- e'. c i e 1- s, e,.ectric znd -na-re@6ic rece-,vers a.- e y o-L@' a,-, abso'Lu@.e new underwal-er 23. The e lectric oraans of Sternarchus albifrons, a South American fre2sh ,%,ater weak electric fish, have been studied with emphasis on electro- receptors. The morphological and physioloaical characteristics of electroreceptors, ampullary and tuberous, were investi-ated. Special instrumentation required for establishing the role of these electrorecep- tors2 in object location, detection and identification has been developed. 24. We have recorded with microelectrodes the autonomous autorliytlimic electrical activil&-y of the tonic asynchronous ampul'Lary electroreceptors of the South American weak fresh water electric fish, Sternarchus albifrons. We have also recorded the electrical ac2tivity from the asyncliroiio,,is phasic tuberous electroreceptors and of the synchronous and asynchronous ampullary electroreceptors of the same electric fish, Sternarchus albifroiis. Preliminary measurements have been made. The auto- rhythmic 2-ctivity of the ampullary electroreceptors ha1s been demonstrated. The electroreceptors are part of the complex lateralis line system of the electric fishes. 25. The other 1,,tteralis line system sensory receptors, like mechanical receptors and displacement receptors, have been discussed as part of a general hybrid object detection, location and identification and reco-ni- tion system of the fish. 2 26. A study of the anestlictizin- effect of tricaine-meth,,tnesulfoiiate (MS222= FINQUEL) on Sternarclius albifrons has been undertaken by plottin- time for the anesthesia anci recovery for different specimens. The anaestlietic does effect the pulse-rate and pulse-shape of the discharge of this fish. An,,testlietic ol-her than "Finquel" which does not af2fect the electric fish's electric or-an pulse repetition rate has been found. Also, the effect of D-tubocurari.ne and the couliter-effect of neosti(,mine has been assessed for Sternarchus albifrons. Finally, some improvements in the micro- electrode recordin- instrumentation have been made. 27. We obtained some specimens of the African weak fresh water electric 2 fish Gymnarchus nilo-@ici-is. They are supposed to be the xnost sensitive of all the weal,: el@e-tric fishes known. Tocrether with two specimens about one foo+.- long, %@,e received a number of baby Gvmnprchus niloticus about two inches lono-. The baby electric fish were infected with a 5,"4prol--gnia fungus and cou2ld not be s,.,.ved, but we fixed a number of them in buffered formaldehyde and one of them has been cut and mounted in paraffin for histological studies of the electric oraans. Preliminary measurements have been made on the communication capability of adult Gvmnarchus niloticus. 28. The electric discharoe of Malaoterurus electricus, an African fresh w2ater strona, electric fish, has been measured in and out of water. Its elec4L,ric organ.can discharue bursts of impulses of 100 to 350 volts and currents to about 40 ni.A-. In general they can put an electric power of about 1000 NvatLs per kiloaram of electric tissue (1 watt electric power per gram of electric tissue). From our inves'Lit-,ation, i2t can be con- cluded that electric fishes could use their electric orcyans (transmittincr and receiving in other words, under- for navi-,-Ition and communic,-,.tion - t@ water object detection, location and identificationlisin- an electromac,- netic s5ystem of detection. 30. The physical -"nalorrs of tonic and phasic electroreceptors liave been t) established. Both are represented by ,i generator connected to resis- tances and cl-@pacitai-ices in series and in parallel. The difference between tonic and phasic clectroreceptors is that the firs+. ones have one resistance in series with the -eiierator whereas the phasic electro- receptors have a c-"picitalice. The tonic electroreceptors- seem to be predominant, maybe lilr.e five-to-one, compared to the ph,,,.sic electro- r2eceptors. The electrorecepl-ors seem to act, to a certain extent, in- dep-3ndently of the main electric tr,,insmittin- or-an; -.t least two out of three different types of elec@.roreceptors are asynchronous and only one type of electroreceptor -%vill synchronize with the mlin electric orcan. It has been fou2nd that the complete denervation of the transmittin- electric org-"n does not stop the activity of the asynchronous electroreceptors (both phasic and tonic). The fish is still capable of respondincr to conductive and nonconductive objects placed near the fish's body. It may affect the to-il.-P,l c,,tpabili-L-y in determiniiirr certain2 movements or impair, to a certain extent, its sensitivity in object reco,,.ni.tion. Some of the synchronous ton-Lc units are connected to one and the same nerve truni@: part of the acoustico'-Iateralis system but connected to specialized bi- nuclei in the brain. Tho- mos4,- stril!lincr fac-L- about2 fresh N,.,ater we,?.k electric fish, besides their spontaneous electric organ, is that all of them are provided with a highly developed lateralis line system. Related to this acoustico- lpteralis system is an enlar-ement of the cerebellum, especially in G@,mna.---hL,s ri-l-o',-ictis ,-nd in mormvrids. T2he unusual importance of the lateralissysteniintiiesefish, comparedNvitholo-.herteleosts, isnotduetoan inc.-el-.s-- nunal.)er of "ordi-ii--ry" lateral line sersory organs, but rather to the existence of a great number of specialized sensory organs within this same system. This is suloportincr our hypothesis about a hvbrid comp2lex underwater object detection, location and identification system used by electric fishes in recognition of prey, predators, and navigation in general. It is recommended that the other lateralis li.ne systems from different fresh water weak electric fishes should be studied with the aim to find out their role in object detection and navigation. II. CONDITIONING TECHNIQUES APPLICABLE TO THE ELECTRIC RESPONSE AND BEHAVIOR OF SELECTED ELECTRIC FISHES Sum in-,., r A study described in this section is desi-ned to identify the type of conditioniii- techniques (operant or respondent) applicable to the electric re2sponses of selected electric fishes, with particular attention to those procedures which can be used to assess the "dynamic rancre" of the re- spoiise with respect to major electrical parameters. Several additional belit;-I,i,ioral studies of electric fishes are also described in some detail. Intro,,iuction It was mentioned in previous sections of this report that certain fish possess orcans capable of meneratin- electrical discharcres; and, at least some of these, have electric receptors that are capable of detectin- and discrir,iinatin- aiiion- different P-atterns of discharcre. This study is focused or. deterrii-iiii2- the 2 to i@,lhich the electrical responses of selected sp-c;c- can be brourrht under the control of respondent (classical, Pavlovian) and/or -raiit (il L-Ai k i a, op , Istrumei-ital Thorn i) conditionin- techniques. (Skinner and Keller and Selioenfeld.)2 The results v.7ill 2 then be examined to determine -whether or not sicnificant relationships e--cist betv7een tlie type of con.,'A;,t;Lo,-n?,7 operations rvhich are applicable to a particular response and pliysioloc,,ical data coilcernin- the structure of the oro@an, the t@,pe of tissue from which it 2 vias probably derived 2 the type of neural innervation and control evidenced., its electrical characteristics, and its functionina'. These questions are of considerable interest in behavior science. Viewed as operational definitions (Feig,3 and Franl@4) the two sets of con- di+lionina operations subsumed respect2ively by the labels, "operant condition- ina" and "respondent conditionin-'?, are clearly different. The controversy ii the literature of the last decade or so concernincr the kinds of learnino- Y;hich exist has not usually been at the level of experimental procedures and re- sults (i.e., of operational def initioiis) here assumed. Instead2 it has con- cerned such questions as the possibility of reducin(,r both types of conditior-in.- to a common, usually unobservable, intervenina or medi-tinrr process; wi'L,h the nature of the postulated process; or, with the type of theoretical formula- tion (Estes, Koch, et. al.)5 considered most promisin- by the 7particular r> 10 - --- --- - - ----- Skin iierii 6 for exaiiiple, prefers the descriptive, Ca'- C:- B7, 2 Cal 3u.:)Cz: 7 az --'s ..,C! as ol O--" -Lhe @L%VO types 0, A.0 va_,-Cui pi-cczss 2 Z- s a:,. u r. or-L Or L aSSOCIL... AS -eSU@ Y, O Y:, e :s evc"-O-)=.Cn@ O', -IO 10 2 11 12 as, - c,-@ n-. co C- ans o@ t..e 13 14 2 AA a:.-, e:'eA7. We-y, 1 5 pzocess,-2i as Al@: C2iCL6@- -az. 0 -.wo O: i.,Ae level. O:- onera,:, 2 -.zr s a.-, L W c@ r'.11-1. C!-asses Of cz.:i L :O a; C C _rl ions 2wn:.Cl:i .C e:_-c -V o nz a s z. z- o u n '6o C res77,o.-.-c-7, cr y e; Y 2 es, w--.:.c.-. 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Li0 2 tro -' C) OA 2 t,3 Us O' rip 4 lip (is Cf Ul (P I j 2 I., C LI) oq @i 2 0 aq Ell Ell C) 0 ri) 2 :1, ri 0 (a 'Li 04 :1 (f) : @:. 2 0 S Eli (LI C. , I #I- v , 2 P.. ii 0 0 tn (D 0 2 r CL ril 2 LI t En 2 ri: tz Ck) ti) CL 2 Li (f) El: e 2 ri c, C) Lf) o LI) 2 -. I I 0 (J Ell ri, 2 Ij, ro I$ rj EO 2 CL Ell O C) cn 2 (D ul 2 f@ 0 ri CL r,) 10 2 v, r Ili I 2 ei 0 ri 2 0 IP 0 0 02 r. , + t(i ;$ 014 t 3 ri fl) ij-1 Ul LJ 02L, k-c. 1, co.,cl":S:O.-is !-.:,,s to i:-. c-c@, set 2 1-ja Y, a,-alys:.s of "4-"Ic 'cc va2,--@ab'cs, a C -o- i:: o o:' va,.-:.ab'.as oba con',-ro',-.'Lcd or c.-@ c v 'L 2 C C !C'Ll C:3, c..Icr o 6 1 ca-. be r-O.- s w!,,.,. c h b,2 used a ---ve,@ !:-S an--@ 51 64 61 C::. 53 62 2 Z..-. .3 0 -;,:n 7 1.0 sa4-ve a.3 -Ls O%V'-@ co--zrc,,, r 2 ,-crs,er and -,29 6 3 v C: a a ia S Z, n a. e e a -red :Z -a, @o ac-:Cve a:-,y C,,*' con,..-o' over occurre-ce oz, cr ove.- 2"-c-- O.L a given siz, t'- a C, S' @o and would ra:se a-@cT c -,:.a i G- -..3 zLs-. W@are -;-o --e o a - 2 Was &,he ex.-,o@.;.onsL or ri C o n d o.-i o-I -,',-le BL;c@-A as -60 aL-"@Ve.-sr:!.y aiz".@ec,* se' 4-o -00 zz. 2 ."i. 6 -i.e., wcul-@' so,-ne o"-e.- c-c)- c;a A. 1 o 2 a:..Ly Way? We:-e t@A-,e cr":d, co-: se 04 -.-:,ua',",y pr2cv,-Ldc sc.--e ev:.der.%-e. A. w- -,e h- -,hly desir,-ble. wit- every species, to S A..L IL;Z) 2 ccrve@-.:Ler"i. res:-,ondert C. C ""'A. e a r,; 6 4) a n d a -ol. Then, a 65 e 66 6 Lo serve as a d of cor,,'@ +,he exocctod resul@6s, as appi.:-cd 26 a.-, a ',-t c C S 0 o 4-.o n - CC .,,,Lcrl i C -6@ on a C.. o ot',-.cz- :no---trs, icird o-i" aid P- .,6 2,7 References 1. B. F. Skinner, "Tlie Behavior of Or,--nisms, Appleton-Century-Crofts, New York, pp. 457 (1933). 2. F. S. Keller, and W. N. Sclioenfeld, "Principles of Psycholocry, Appleton- Celitury-Crofts, Inc., pp. 4'#3'1 (1950). 3. H. Feicrl, "Operp-t2ionism and Scientific Method, Psychol. Review 5, (Symposium on Operationism), 250-259 (1945). 4. P. Frank, Foundations of Physics, International Encyclopedia of Unified Science, Vol. 1, No. 7, 1-78 (1946). 5. W. K. Estes S. I-@och K. 1%1,,icCorquodale, et al., Modern Le,,irnincr I I 2 Z> Theory, Appleton-Century-%r.rofts, Inc., New York, pp. 379 (1954). 6. 'L 7i . .o 7. y 8. -7 1-0 y es i, 2 9. @ro.s., 1:)-). a. o 10. y, 12. o' %@c s z,.d ,Ver., 13. 14. a,-Ij @,r. @A A. ard T e oT e 4 l@..z Lai. %IC J W 28 co cn 2 Li 0 2 I ci I ij t 0 f.. 2 Eli t.4 tn (o f- 2 (n -1 P) r t)2J I o - I- (" C', (, a C; . I C) ('. ti) t .. 2 C) C)i fit ' v' 2 "J ci En 2 Cil # . 2 IN ci 'J 4 2 r Ic@i (i) 0 r) 0 P.) 0 ri *,r 2 .1'o CL)o 2 ht'.. 11 act 2 cti ki C) 2 En C,.) C,, L(J 2 El tn 2 r. 0 2 fr 4 r, n 2 r) 2 ti) E. 6-1 2 co I ) Vk I 2 v til 13 CY3 C,i o .. 2 .11 co (D "U 2 C A 2 14 @t F C I I ,* 2 t,3 ft) t,I . 0 I- 1, t d E 2 Ld 2 td @l cn 2 C) 0 2 (L fit 2 03 rL 2 G3 C) ul -4 2 rv # t. Id 2 En rv ri f. tit 2 L-)0 7 I' C,#2 C4 C03 2 co w C.4 $-A (D to C4 C.3 2 C4 C;" t.1 to 2 t Li fjj 2 C U7 2 E., ui C Lit C..) 2 t@j C-1 Li tj 2 0 tn J- u 2 'Li Lii t-J C.' m 2 C or--I -3 ul In --1: tl - .,. to.- 2 J cti tq 2 C,3 .1 LJ 2 C" 0 cf) 2 Co It- c@, CD Ln 2 (J 2 tri V I J C2T) Cj tn 2 CL CD L's fit 2 CL) Li CL, 2 C.1 1 Er) 11.1 rLA tij IL11 2 C-) C,3 rv U) t'll C 0 2 t, . 0 C, Le) C) 0 2 P.). C. 8 Pj (Li C.) C. Cl a Ef2) tit C 2 Lr) t' C) 2 1 (D tit t i (D 2 v CL t- I L,J 0 o 2 o cjl r tn C, 2 oo r Eli 0 2 L CD En 2 lij Li 0 2 pi . C) 0 t,J CO 2 -3 0.1 % 2 114 En En (D 2 Li Ul (f) tj C.3 cLi 2 I.I. tn "kl 2 0 t t. En tn 2 C, . ) 9, @. - Its .1 2 I U Eli 2 4-1 C.@ . Ill. tn 2 fit E(i I,.- 1,1. 0 2 C-4 t Ef) C.) Eli C) 0 Ulf# t t C, 51. o V 52. 'Yi f C A. C .?, 0@j 53. a Pes7oo.-Lse A.,-i :3,2n S 2 Yi, '-O:-3b!e:.n o'le C S, 54. j. A. Vai-nc 7 9 6 1 or s e,:-. C h.. Bat, s,2 55. -lec+-:ccl Sz',:-:;es 'Powe.-s, ".r_i 56. s, A. R. V r 57. a.-.- :)as, 53 2 Des-.-,n- ;n '->sycholo-4cal '.ResezLrcft, 59. w,-,-.- r- s ,@x. -@w Yo:-'.c , i-4u L950 0 W; s kalso ',960). 610. -,-i W: 'Cy Sons, pp. 'I.9,@,2 61. 'Y 62. 63. 3 2 ys 64. 65. -W OL 6 6. III. PROPOSED I3EII.,%VlOrtAL STUDY OF ELECTRIC FISIIES IVITH EL\IPI-IASIS ON OBJECT DETECTION, LOCATION, AND IDENTIFI- CATIO!I (PHASE I) Three different kind of e-.%@periments ,ire proposedr,,,ith the aim to ,issess the nl)ility of electric fishes to detect2, locate and identify objects under,w,,iter. The first svstem is desicned to use as a subject, a weak fresli--%,,,-,iter African electric fish GNmiiarcliiis niloticus. A maze has been desi-ned (Figure 1) to be built in a water t;anl,- of 12 feet in diameter and 4 feet in heioht. The maze has two channels supported by2 bars on the tank. The fish located at C will be presented with a stimulus in the form of objects (met,,illic, nonmetallic, ma-netic and nonmat7netic) of different sizes either moved from D to E or from E to D. The reaction of the fish and its choice of the ch-,,.nnel vrill indicate how %,,iell the subject v..,ould detect 2different objects of different textures and sizes. The fishes are freely sv,,Immina. The second system, (Figure 2) is desicrned to prove the ability of eleC"Lri.C fishes to avoid obstacles lil"-e fine aluminum -r.;,ire or nylon '.Iirea%"A- The African electric fish Gymnarch-,is nilo'Licus and the South-American 2 electric fish Sternarchus -,,.Ibifrons would be used. Both fishes are blind and use their electric transmittin--receiving,, system for navio-ation. Gymnarch-as has a very steady frequency (around 300 Hz) and Sternarchus has a steady frequency (around 750 Hz) provided the water temperature is held constant. The fishes v7ould2 be presented with stimuli (attractants and repellents) and their behavior ifLI1 be monitored by filmincr it. The fishes are freely swim- mina'. The third system is designed for variable rate of pulses electric fish species like the South American fish Gymnotus caripo or the African fish Gnatlioiiemiis petersii. The subject will be confined to plexi-7lass tube vath holes and two electrodes (at the head and at the tail). The impulses emitted by these fishes will be amplil'ied and monitored witll an oscillo- scope and a frecrueiicy counter. Objects (melillic and nonniet-,illic) of 34 diff erent sizes would be presented f rom diff erent dist,,i nces and their eff ect on the fishes pulse rate will be recorded. Gr-,iplis will be plotted relating material, size, and distance to the pulse rate as compared with the steady- state pulse rate. These fishes increase Uie pulse rate when an object disturbs their electric field -ener,,i4ted by the traiismittinc, orcran and re- ceived by the electroreceptors in the skin of the fish. It is hoped that these three sets of experiments will show the sensitivity and ran(re of detection of, different objects by electric fishes. 35 114 4L rn 2 co -6-0 2 ct 36 0 Ca rn ct 37 co Ar@ Li 2 co,'C s is c opo, Gnat IOP-C , ' " ' ' " I MLls 2 Vmnot 'ir equ'ncy Elect,,ic Fioche for Variable Fr t-I -UP 1 Exoerimental Set IV. AN E@:AMPLE OF HARD@%IARE ANALOGUE EXPERIMENT TO SIMULATE OBJECT DETECTION BY ELECTRIC FISH (PHASE III) It is possible to simulate an equivalent sensory system of electric fishes respondina- to different stimuli underwater. A system with a double feecF)ack-mechanismcanbeenvisaged: (I)onerepresentedbya.constant frequency electric field transmittina2 system operatiner on the phase-syn- chronous electroreceptors respondinc, to discontinuities in the electric field or to changes in the phase relationship transmitter-receptor; and (2) another one represented by a variable frequency transmitting system respondincr to disturbances in the field between transmitter and receptor t> with a chancre of the frequency. of the transmittincr electric organ. To t2his t@. t;l -we could add an independent dual autorhythmic receptor system: (a) re- spondinc,r with the increase or decrease of the authorhythmic frequency dependina on movement direction of the disturbance in the electric field; and (b) respondincr with a chan-e in the latency dependino- on the magnitude of the disturbance, and also distinguish2inr between conductive and non- conductive objects. A simulation of the electric fish object detection system would mal,,e it possible to find out how models of the physical analogs of the sensors could be integrated in object or oraanism location, detection and identification. The ranme and sensitivity of the system could be assess- ed and improvements could be made. As a first step toward this simulation 2 we present a measurement plan for an experiment in Phase UI of our investigation, to build and check the first of the above mentioned mech- anisms for detecting, locating, and identifyincr objects underwater by z@p t;l means of a phase detector system sensitive to ch,,i,-i-es produced by dis- continuities in the electroi0-r,,,i-notic field. Systems -,iiid equipment for detection and location of objects in a sea- water or fresh@,j,,tter meclium have to be desi-ned from the standpoint that the 39 medium is lossy -,ind li,-ts -,i hi-"-li dielectric constant. Consequently, the -wa-%,-elen-tli of a si-n-,il transmitted throu-Ii the wa,@er medium is different that ih.-ILt of a si-n,-il of, the same frequency transmitted throuch free space. t@ 0 Attenu2ation and scitteriii,-r are ,tlso different from tl-ie values for free space. The advanlicre of usinr a phase comparison', position determin- incy system is evident because the precision of our measurements depend on the phase measurement precision cap,,tbilities independently of the frequency used. This gives us the possibility of usinr low frequency com- 2 CP bined with a highly accurate phase measurement. In free space we have the well-known relation between the speed of light c, the frequency of an electromacn--tic vrave beincr propacrated f, and its -%ravelencrth c f ',k (for all X in free space) In seawater, this formula 2cannot be used because the propaaation 0 velocity of an electroma-netic wave is different than the value of c in free space. Moreover the propaa,.-at-J'.on velocity in water chan,-es with frequency and is not a constant. It is represented by the relation 2 2 s = F where S = Function (X s = speed of propagation in v,,ater dependent on the electrolyte medium. f = freouency (Hz) lkt waveleii-tli in water (meters) The sigmal travels a distance D in the time T where: D T = S 8 Tal@on f roin D. L. Nichols reports 'Lrom the U.S. Navy Underw,'Iter SouliCt L,,iboraLory, New London, Coniiecticut. 40 s,is dependent of I @nd A:. NVitli respect to time zero the phase of the ,rated si-tial advances tlirough Ll,,e -tngle 2-.r fT. The received si-nal th@m-efore behand the signal at the signal gene7x-ator by 2.7r fT. If this phase lag could ured, the ran-a could be calculated. The basic equation for phase- .neas np2arison distance measurement is D p =ZrfT = 2-,rf s ,ere 9 is the measured phase difference between the reference signal and the ,-nal,%vhich has traversed the distance to be measured. In terms of the .stance traveled, Sp PkI D = - - 2 2-.r f 2 7T 'hase measurement can be based on: (1) the multiplication of two cosines or sines) and integration over one period of the function; or, (2) by deterininina 0 -he instants at which the reference and text signal cross zero in the same direction and measurina the time be 2tween the zero crossincs. The phase ancle is then Z-r,f T, -%v"Pere T is the time between zero crossin-s. We have chosen some hypothetical parameters for a phase disturbance detection and location system. The values chosen may have to be modified according to our findings duriiic, checkin-, experimentin-, and making measure- ments in a scaled model in fresh water, sea water, and mixed fresh and seawater2. The parameters for our system that have to be scaled down are: Transr.ni-tter- f = frequency = chosen between 5000 Hz and 1000 Hz = len,-th of the antenna made of a water column in sea water bet%v.eeii 22 m and 50 m p = enclplates for the antenna feedin- betweei-i 25 and 50 cm diam. silver silver c2hloride plates on Mojictl-nietal 1/8 in. thicl4ziiess; plzltes v,,ill be fed by coaz@-.iil cable in a coppertube 112 in. diam. 1/16 in. wall. tliiclzncss sprayed with a tcfloii coatinc, of iiiiiiimum 1/32 in. thicl,@ness. L* Transmitter power effective dcli%,-cr3cd at the (@iidplates 1 Ir.W. Transmitter 41 y be in a screened room, double copper mesh, with a good ground to al) endent ground. Transmitter has to be crystal controlled. .ntenna depth = 3 to 5 m under the surface of sei level. tecei%,ers- Instead of dipol,e antennas, low-loss toroids will be used, tuned to between 5000 Iiz and 1000 I-lz frequency fed into matched lines and to low-n2oise linear amplifiers. The amplifiers have to be non- phase distort type. Phase active networks conne--ted to the ampli- fier %,ill correct-for exact 1800 phase opposition of the toroids' output. The output from the phase-corrective networks W411 be fed into a variable hi-h-gain (decade amplifier) differential amplifier where the output will be monitored by a scope and a null detector. 2 Differences of 0. 001'Yo may be -Dossible to be detected at the hiahest gain.- Scaled Model: George Swain'-- tried-an experimental toroidal antenna scaled to small diameters for frequencies o 1. 2. 0, 3. 0, 4. 0 and 7. 0 lv!I-lz in a solution of NaCl of 0. 285 moles per liter and a conductivity of 7 2. 8 n-ihos per meter at 250 C in a tank 3. 5 m in diameter and .55 cm deep. George R. Swain: Antennas in or at the Surface of a Conducting lvledium at 'LF, Report EE-116 of the E. E. S. Univ. of New Me:@dco, Albaquerque, M. (I 9 6 4). 4 2 ,t is proposed to use a plastic taiil,@ 12 it. in diameter and 4 ft. deep fo,- ed do-,,%,n experii-lient with fresh aiid seawater. IVe will increase the frequency to 400 kHz corresponding to a wavelength vater of 2. 25 m; also tan times smaller than one of the hypotlietical values. endplates of the antenna will be 8 cm in diameter (about 1/10 of the surface 2the hypothetical plates). The power of the transmitter will be decreased 100 W at the end plates. Antenra should bc- submer,--ecl io a deptl-i of from to 50 cm. Receiver antenna will be made of corresponding toroids for the frequency f 400 kHz. The ratio of the attenuation between a signal of 5000 Hz at 22 m nd 400 1<-Hz at 2. 2 m distance be calculated and the factor applied to th2e ,esults of the measurement. A piece of cotton filled, cotton cove'red, and partly isolated cotton body %vit',Il a volume of one-tenth that of a human body and with similar conductance ,,-,ill be used to find outthv. phase deviation produced in the field in different positions between the transmitter and the receiver antennas at different depths. A device for makin- artificial measurable waves on the water surface 2 will be used to produce scaled down waves. A random-noise generator will be used to simulate natural noise which will be added to the signal for different SIN ratios. Polarization and position clian-e of the toroids will be checked to find out if it is possible to reduce the unwanted effects of water movement and noise. The temperature and the salinity with respect to the conductivity of the water be continuously monitored and recorded2 durii-i- experiments. Receiver and tran@ei-nitter antenna will be checked under steady positions and small rnovemei-its to determiiie the effect of mo-,,ing the antennas on Athe 43 - - - --- - -------- - ------------------------ 3nse of the -.ystei-i-i. Q-factor of the toroids in air, fresh water, and -ater will be measured. The ratio b'et-,veen deviation procluced by waves or noise and the one produced by the object @,ill be determined in order acide if a full-scale experiment is warranted. 6 Ao Simplified Block-Dia-ram of an Underwater Pliase-Detector t@ System Used to Detect and Locate Objects 44 Ratio Divider u I Detector Example of a simple ratio bridge. 45 71 Ag Ag Cl Imp-2dnncc i-,'Icctrodou AVater T.-ni.,. 2 3-5m in Ctin,notor 60 to 150,-.i tloop Trni-ioriittor f" made of I)lr..,i2tic 100i'l ".2m Toroids Ir Ph-ine Cori-ecting 2 Pi c cting Netr;orlt inno orro Oocilloneopo Ilull Detector a 0.1; le lo-, 100; 10100 Scnlc(l Dorin f or Eicperinonting Mirpo!3o of n 13]inse DirL%rinjination Object 1;...f-Lctioji nnd Location System in Fresit aiid Sen%ynto- Ph 3 I Al A 3 Calibrated Cathode Fl Range 2 Multiplier Amplifier Phase Shift 'Filter Follower Ml 0 B NE5 ull 2 0 crational Overload Bridge Aiiiplificr (Gain 100) Alarm Differential Aml)lifier tional 2 A 5 fier (Gain 100) T 180 Filter Range Amplifier Calibrated Range Cathode F2 Multiplier A4 Phase Shift multiplier Follow2er Ph 2 M4 M2 A2 -up for demonstration of the 'ISystem for Detection Proposed experimental set water or Freshwater Medium. 6 of Objects in a Sea and Location