Doc 0000173534

- I. Summary of Progress A comprehensive series of runs involving a variety of electrodermal and other physiological measures has been completed on a population of 26 subjects under a variety of task conditions and contrived psychological "sets" to assess the relative sensitivity and reliability of various electrodermal measures, _Including the recovery limb time constant. Assessment of impulsivity and anxiety by psychological tests as well as a psychomotor test of inhibition have been obtained on the subjects. Data analysis is still in progress, but some preliminary conclusions have already been drawn and are reported here as an interim progress note. Runs on a separate population of twenty subjects under a -different set of stimulus conditions have been used to examine the dependence of recovery limb time constant upon base conductance level and response amplitude. The initial study of the vascular component in the skin potential response has been completed. Development of the automatic measurement of recovery limb time constant has progressed to the point at which a system is now availeble, using first derivatives, which overcome many of the difficulties of the earlier approach in \Vhich second derivatives were employed. The new system has been used to print out the time constants for 22 subjects whose datt. had been stored on magnetic tape. These data are now being subjected to statistical evaluation. ll. Study of Characteristics of Recoverv Limb in Relation to Other Electrodermal Measures a. Dependence of Recovery Lirnb Time Constant on Base Level. To determine whether the apparent relation. of recovery limb to nature of the stimulus condition was to be explained by differences in base resistance level, compe.risons Approved for Release \ Date I 2 H:S ~73 - 2 were made bet\veen base level and recovery limb time constant for 21 subjectB 1n two conditions, each of which caused activation and consequent decrease in base resistance, but with different degrees of goal oriented task demands. Means for the two situations were as follows: Backward Counting Condition (by sevens) Cold Pressor Average time constant (scale units) 17.1 21.7 Average base resistance level 29.5 K 27.6 K These de.ta indicate that despite the fact that the cold pressqr task was, if anything, slightly more activating (difference in level not statistically significant) the time constants were significantly different (p ( .01, paired comp.:'l.rison), the difference is therefore no~ c:.ttrfuutable to difference in base level. It is to be expected, however, The image displays a digital representation similar to a webpage or a document header. On the left, there is a graphic of a stylized vault door, a common visual metaphor for secure or hidden information. To the right of the vault, prominent white text reads "THE BLACK VAULT" in a distressed, stylized font, immediately below which is a block of smaller white text. This text explains that the document was obtained from "The Black Vault," an online database of declassified government documents, specifically mentioning the MKULTRA/Mind Control Collection, a compilation of over 20,000 declassified pages from the CIA. At the bottom, a yellow URL, "http://mkultra.theblackvault.com," is displayed, indicating where the full collection can be accessed. This visual composition serves as an introduction and source attribution for the declassified information. The page is a typed document with some handwritten annotations. A circled number "154" appears in the bottom right corner, along with a date "27 FEB 1973" and the phrase "Approved for Release". There are several handwritten marks that appear to be edits or underlines on the text, particularly in the first section. The document appears to be a report detailing a study on electrodermal measures and recovery limb time constants. There are no photographs, diagrams, schematics, or structured data tables visible on the page. indicate that despite the fact that the cold pressqr task was, if anything, slightly more activating (difference in level not statistically significant) the time constants were significantly different (p ( .01, paired comp.:'l.rison), the difference is therefore no~ c:.ttrfuutable to difference in base level. It is to be expected, however, that subjects who show greater activation for performance of a task might show a reflection of this 'mobili'zation both in base level and in recovery limb time constant. Accordi..'l.gly the correlation between base con.- ctu.cta.nce and t:ime constant was determined for this same grcup of subjects during the backward counting task, and it showed a significant relationship (r = - .49, p (.OS). ?or the cold presso:r situation where the ac:ivation is presumed to be of a different qu<'-lity, the correlation. was considcra!.,ly les.r. (r = -.23, l'~.S.) - 3 b. Dependence of Recovery Limb Time Constant on Response Amplitude Although the time constant of an exponential decay should, if properly measured, be independent of amplitude of the curve, there arc many conceivable reasons for suspecting that such may not be the case for the electrodermal response. Accordingly for each of 12 subjects, time constants were compared with peak amplitudes (con ductance change) for 30 sequential responses taken across four experimental conditions (rest, perceptual task, cognitive task, perceptual-motor task). The Pearson's correlations are shown below: Subject Pearson's r Sub.iects Pearson's r 1 .29 7 -.04 2 -.29 8 .14 3 -.06 9 -.04 4 .43 10 .03 5 -.25 11 -.06 6 .15 12 .00 Tne independence of these two measures _is well demonstrated. Some negative correlations might be ~-pected because demandi::lg tasks could produce higher responses and also, because of the nature of the activation, shorter time constants. For most of these subjects, however, such was clearly not the case. c. Dependence of Recovery Limb Time Constant on Qualitv of Task A studf 'vas U.'ldertaken to answer two queEtions. 1) Does the recovery limb vo..ry as a fun:::tion of the perceptual, cognitive, - 4 or motor aspects of a task. 2) If it does so, how does its specificity and sensitivity compare with those of more conventional methods. A. Method Twenty-six subjects were used in an experiment in whic;h three tasks were performed, along with associated rest periods. In order to exclude the variance known to be due to the operator's mode of instruction and his relation to the The page contains a table presenting data on "Average time constant" and "Average base resistance" for two conditions: "Backward Counting (by sevens)" and "Cold Pressor." The table shows numerical values for these measurements under each condition. Below the table, there is body text that discusses the data and its implications, referencing statistical significance and correlations. There is also a handwritten annotation at the top right, consisting of the numeral "2," likely a page number. The document appears to be a scanned copy of a research paper or report, with a horizontal line segment at the bottom that may indicate a stapled or bound edge. and sensitivity compare with those of more conventional methods. A. Method Twenty-six subjects were used in an experiment in whic;h three tasks were performed, along with associated rest periods. In order to exclude the variance known to be due to the operator's mode of instruction and his relation to the subject, the tasks were programmed on video tape. 1. Cognitive Each of a series .of 12 RaYens ~/'.a trices Problems was presented for 30 seconds followed by a 15 second rest period. Tne subject was to choose the pattern which properly completed the matrix and was to report only after the given problem dis appeared from the screen. Responses were chosen only from the period in which he was solving the problem. Obviously, conta.mblants such as visual perception, frustra tion, etc., were present, but it was hoped that the group result as a whole would be heavily weighted by the cognitive performance factor. 2. Percen::ual A fixed pattern remained on the screen for three minutes. At random intervals during this period, it would cllsappear, momentarily (40 msec) and for a total of 18 times. The subject was to continuously observe the pattern and after the end of this task, upon command. report the number of cllsappez.rances. All useable responses durin£ the obs erv-a.tion period were nrw l;rzed. \ - 5 3. Reaction Time A series of five reaction time trials was used, each having a warning signal and a 10 second foreperiod. Measures were taken at the time of the reaction key press. 4. Other Measures a} Behavioral. In addition to the above, two psychologlcal tests were administered to these subjects, the B.'lrrett Impulsivity Scale and the Spielberger Trdt An.xiety Scale. A beha viord test of motor inhibition task was also administered. task,~~~eQ;~~;_gua.-in..vestigato;:·fhe In this subject is told to turn a knob through -.....,. ''·--~ 180 degrees, continuously, but as slowly as he can. Inhibition is assessed by the total time taken and by the degree to which rate is accelerated as the task progresses. b) Phvsiolog'ical. In addition to the skin. conductance measure, skin potential, . cardiotad:.ometer recording, respira.tion (mechanical pneumograph onl}') and frank perspiration were measured. The last measure was obtained by a modifica.tion of the photoelectric prism method previously described. The device has been improved to eliminate vasomotor artifacts and to allow use of a lightweight unit secured to the finger tip. -- ------~~-- f ------- . (mechanical pneumograph onl}') and frank perspiration were measured. The last measure was obtained by a modifica.tion of the photoelectric prism method previously described. The device has been improved to eliminate vasomotor artifacts and to allow use of a lightweight unit secured to the finger tip. -- ------~~-- f ------- . . 5. . . -· . -- . : . ·,__ """~ ~~~~ve-runs-;-~test-s-were·rwi.-.on--24 s~jects to\dete~1. ~ /,. ....... of·the . ' ' 1 J ~ I r·mb · 1 r;' I ( j sens1.t• 1y• ,.l. cy,.o .... tn• 9 recov~ry 1. tlme cons/t f ord e tectm· g s u 1 bt 1e c1t.. anges-c t emou·o oa j i I / i / I , ; cet':- {test was adopted for this purpose and we.s used·uoder'' i .:' I • .! ,f ' ' ; ! I three--difierent-dem.:!nd·situations-:--· The use of video tape was again hd~fur·iri'redudng · i I ! ! . Ciff2rences-·ir. 'operator. cfic:ct• . _.Th(.!_.subject was prescmcdfour.letters and asked to i ! ----------· ) 6 -~ 'l choose one and v:ritc it dcm11, to be turned in 2.ftcr the task was over. He was then presented a screen in which these four letters appe.:trcd in a new order, the group being preceded by three other letters and followed by three more. An ~rrow 1 I /' I appeared and pointed to the fimt letter where it paused for 15 seconds. It then moved i / . on to the next in the sequence and again p.:1.used for 15 seconds, etc. T11c subject / ; knew in advance that this would happen in regular sequence. In the first such test, { . / \ the subject was\ o simply observe this sequence witbout any vzrbal report. In the \ \ --------- _/ \ second test, the identical sequence t -----~------· '\ f In a third series run on \ /--- 13 of these 24 subjects, \ the su.')ject w<:s ' t old that he would earn an extra dollar if he \ / managed to successfully· -, An entirely new series and n~w \ / \ / 1;were used. At the' end of the previous two tests be had been told the _/\ -l operator's conclusion as to which \of the letters was -- -- -------. This ti:ne his \ "set" had been altered by his knowledge of the operator's previo~s success and by \ ' the The page contains text and a table. The text discusses an experiment measuring the time constant of recovery limbs and its relation to response amplitude and task quality. Above the text, there is a page number "3" in the top right corner. The table presents data on "Subject" and "Pearson's r" correlations, split into two columns labeled "Subject" and "Pearson's r" and "Subjects" and "Pearson's r." There are no photographs, stamps, handwritten annotations, or any visual evidence of experimental procedures or equipment. The content is entirely textual, presenting research findings and data in a structured format. 1;were used. At the' end of the previous two tests be had been told the _/\ -l operator's conclusion as to which \of the letters was -- -- -------. This ti:ne his \ "set" had been altered by his knowledge of the operator's previo~s success and by \ ' the adced incentive _i Again he was to respond "no" to each letter. ' \ \ \ B. Results to Date \ \ \\ Analysis of these data is still in process, but some early results may be \ \ presented. Follow-up progress repons will be marie as calculations are completed. I \ 1. Data P..ancling \\_ \ \ The tapes were made primarily so that unal)'sis of the~e recordn could be \ made at.:er fu:::tb.cr development of electronic tech!liques for cu.lcc.lation of the time constant. This development went on as a parallel effort durbg completion of the above series of runs and bas since been completed. The tapes have been run off - 7 ,./ ~---·----· and the ""'· ccrlvc.tive proccsst:1:;. ~~c.'lru; and st:md:lrd deviations '"' t.:..ndcr each task condition arc bcl.ng calcul:rtcd in prcy:trution for t-tcsts o! differences i between coudltions. T"o" 'd ::.tc calcula.tlon~ on 12 of the 26 subjects have been compleccd. """' 2. Comparison Detv:ccn Conditions ""' . . . I\To comp.a.ri::;ons ~croG:J subJecm ca:.1 be made until all means und stanc!<:r-d /~ . "" eoviations have been calculated, but intra-individual comparisons between tasks ./ h:l vc been n:ndc for t.'losc subjects completed. ··of 32 possfule compariaons, only // ~ . 3 reached sigr.ificancc; 5 appron.ched sign.ifiCilnce. In 10 of the 11 subjects who """· showed reaction time re_:../; po.uses, the time cor.star..t for thie t.a"s"!' ; wao the shortest of /.· __ the three tas ~.' l':o coUG istcu.t cllffcrencc appears between the C:cg;:titivc and perceptual ··"""- __ // tn.sks tor that part cf th~ population completed. 3. Using the j th~ op.erntor correctLy icer.tified tee con· /// cealed le:ter in the !l.rst sc:::ies for 18 of the 24 subjects. M.oreover, whe:: the subject -, / _ji ::ly "\.:.'as mozivated to monct:rcy ;ewa:rd, the operator ide:lt!fied it correctly in 10. oi the 13 cases. Ill 5 htsro.nccs, the .op-erator hzd fJ.llcd to iden.tlfy '"", / the letter in the first series, but whe:.i. monet::.cy·-revm.rd was added he cori'ectl)r ' ~ ~ __ .J identified the nev; letter for 4 of these 5 subjects. Thc_ __ The document is a typed page with a handwritten number "4" in the top right corner. The text discusses a research methodology, detailing two experimental tasks: "Cognitive" and "Perceptual". The "Cognitive" task involved solving Ravens Matrices Problems, while the "Perceptual" task focused on observing and counting disappearances of a fixed pattern on a screen. There are no images, stamps, forms, diagrams, tables, or redations visible on this page. ide:lt!fied it correctly in 10. oi the 13 cases. Ill 5 htsro.nccs, the .op-erator hzd fJ.llcd to iden.tlfy '"", / the letter in the first series, but whe:.i. monet::.cy·-revm.rd was added he cori'ectl)r ' ~ ~ __ .J identified the nev; letter for 4 of these 5 subjects. Thc_ __ comparlson of '" \ ------. lt is nctewor-1.-hy tb=.t in so1~1e l.nsu:.nce.!:._ in wh!ch sl:in c·Jr.dt.:c~:lcc activity g-~YC :.=-n!:lig-...:ul\S rcsdts, the optka.l sweet rccord!nr; sho'sed a __ __.... ··-------··· - - :; ; • ·:: 'i :: ; •• ;; :· ;;·; - 8 4. Psvcholog'ica.l and Psvchomotor Tests These tests will later be used ns a basis for sorting the population into different types of physiological responders. To date, the individual impulsivity ratings on the Barrett Scale have been compared with the time taken for 180 degree knob rotation. The correlation was unpredictably a positive one for the 26 subjects < (r = .37, p .05), i.e., individuals judged more impulsive b)' the Barrett Scale took longer to rotate the knob, indicating that the type of inhibition measured by the two tasks is different. The Barrett Scale was also demonstrated to give ratings which were independent of the Spielberger Anxiety ratings. Later calculations wUl examine the interaction ~f these scale ratings and physiological fL·Hlings. III. Study of a Possible Vascular Comoonent in the Skin Potential Response This study, involving the effect of arterial or venous cuffs upon skin potential, has been completed on a total population of 24 subjects. Results are highly signifi cant and show that the shL."t in potential can be more easily demonstrated upon defiation than upon inflation of the cuff, and that the polarity of this post-deflation response differs according to the type of pressure cuff used. For venous (engorging) = cuffs (p 60 min Hg) the response positive. For arterial (occlusive) cuffs (p "" 180 rnm Hg) the post-deflation response is negative. The conclusion that these represent vasomotor adjustments is supported by a follow-up pilot study on the local potential responses reported earlier. It had been concluded th<!t the slow component of this positive responee to stretch is of vascular origin. If so, it should be demonstrable even when the epidermis is penetrr..ted. :tvlJcroelectrodes were pushed through the epidermis until the negative potential fell precipitously indicatmg penetration of the dermis. After allowin.?, time for stabilization. increase of pressure on the 9 electrode causes a This page is a typed document with handwritten annotations and markings. There are no photographs, diagrams, or organizational charts. Several sections are enclosed in handwritten boxes, possibly indicating areas of interest or for further analysis. There is a handwritten number "5." at the bottom of the page, and a handwritten comment box that appears to summarize some experimental procedures and subject presentation. The text mentions reaction time, behavioral and physiological measures, including specific tests and equipment like a cardiotachometer and photoelectric prism. There are no visible stamps or redacted content. responee to stretch is of vascular origin. If so, it should be demonstrable even when the epidermis is penetrr..ted. :tvlJcroelectrodes were pushed through the epidermis until the negative potential fell precipitously indicatmg penetration of the dermis. After allowin.?, time for stabilization. increase of pressure on the 9 electrode causes a potential variation. These experiments must be reflned to eliminate the possibility of the "responses" belng only a reflection of variations in tip potential or sweat gland activity. If valid they will offer strong support for a vascular component in the skin potential response. IV. Development of Automatic System Comparison of valuee: for recovery limb time constant obtained by template matching with those obtained by the use of first deriv:ltives indicated the inter changeability of these two methods. The principle involved in the first derivative method is that the absolute steep~ess of the recovery limb is a measure of its time constant for responses of equal amplitude. Responses of higher amplitude having the same time constant will have a greater absolute steepness to the recovery limb. Hence the absolute slope of the recovery limb can be used as a measure of time constant 1f a correction for amplitude is made. In practice tlie simplest correction is to divide the amplitude of the peak slope (first derivative) of the ascending limb by that of the recovery limb. This ratio, plotted against the template readings, gives a good linear relationship. To accomplish this electronically, the derivatives arc obtained by R-C differentiation and the output stored on capacitors with diode input so th:it pe.::.k wlues are obtained. Gating circuits are used to allov.f computation only after both peaks have been stored and only if the time elapsing between successive wc.ves is long enough to allow the recovery limb to reach its peak. If the contingencies are met, a co::1mand signal feeds the two stored voltages into two voltage to frequency converters, and from there to a counter having a.n input for obtaining the ratio of ------~---------- - 10 two frequencies. The output is printed out upon command and the system reset. At the same time as the above occurs, the value of the peak first derivative of the ascending limb which is proportional to response amplitude is printed out after measurement by a separate counter. Thus the response amplitude and recovery limb time constant are measured in a single opere.tion. It is presumed, however, The document is a page of text with several handwritten annotations and lines drawn to connect parts of the text. There is a page number "6" in the top right corner and a faint horizontal line near the bottom, suggesting it is part of a larger document. Most of the page is filled with typed text, interspersed with handwritten notes like "In a third series run on" and "Again he was to respond 'no' to each letter." There are also some handwritten lines connecting different sentences or phrases within the text, possibly to indicate relationships or flow of information. No photographs, stamps, forms, schematics, tables, or redactions are present on this page. time as the above occurs, the value of the peak first derivative of the ascending limb which is proportional to response amplitude is printed out after measurement by a separate counter. Thus the response amplitude and recovery limb time constant are measured in a single opere.tion. It is presumed, however, that most fac1lities will not have the luxury of two parallel voltage-to-frequency converters and counters and, therefore, au analog division circuit is being tested. In this system the two voltages to be divided are fed into a diode division circuit and the quotient, as a voltage level is fed into an A-D conversion and printing unit. This circuit is very simple, and as an alternative the output {proportional to time constant) can be written out on an. ordinary analog recorder. The system then approaches practical utility. The document appears to be a page from a scientific report, likely from a research study, given the presence of numbered sections and experimental data in text form. There are no photographs, diagrams, or explicit descriptions of experimental procedures or facilities. However, there are several handwritten markings, most notably diagonal lines that appear to be annotations or connections between different parts of the text. Some of these lines seem to be pointing out specific phrases or connecting concepts. There are also a few small, scattered ink marks that could be errant pen strokes or minor smudges. The text itself is printed, indicating a formal document, but the handwritten annotations suggest an active review or analysis of the content. There are no official stamps or forms with filled-in fields visible. The document page is text-heavy with limited visual elements. A page number "8" is located at the top right. The text discusses psychological and psychomotor tests, and a study on vascular components in skin potential response. There are no photographs, handwritten annotations, signatures, stamps, forms, diagrams, schematics, organizational charts, or tables visible on this page. There is also no visual evidence of experimental procedures, equipment, or facilities. The page contains only typed text. This page contains text only, with no images, handwritten notes, signatures, stamps, forms, diagrams, charts, or tables. There are no visible redactions or obscured content. The document appears to be a research paper or report, focusing on the "Development of Automatic System" for measuring limb time constants, likely related to physiological experiments. The page appears to be a typed document, with the number "10" in the top right corner. There are no photographs, handwritten annotations, stamps, forms, diagrams, tables, or redations visible on this page. The text describes a technical process involving electronic circuits, frequencies, and measurements, suggesting a scientific or engineering context.