This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ Occipital and left temporal instantaneous amplitude and frequency oscillationscorrelated with access and phenomenal consciousness Vitor Manuel Dinis PereiraLanCog Research Group, Centro de Filosofia, Faculdade de Letras, Universidade de LisboaAlameda da Universidade, 1600-214 Lisboa, Portugalvpereira1@campus.ul.pt This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ Occipital and left temporal instantaneous amplitude and frequency oscillationscorrelated with access and phenomenal consciousness AbstractGiven the hard problem of consciousness (Chalmers, 1995) there are nobrain electrophysiological correlates of the subjective experience (the felt qualityof redness or the redness of red, the experience of dark and light, the quality ofdepth in a visual field, the sound of a clarinet, the smell of mothball, bodilysensations from pains to orgasms, mental images that are conjured up internally,the felt quality of emotion, the experience of a stream of conscious thought or thephenomenology of thought).However, there are brain occipital and left temporal electrophysiologicalcorrelates of the subjective experience (Pereira, 2015).Notwithstanding, as evoked signal, the change in event-related brainpotentials phase (frequency is the change in phase over time) is instantaneous,that is, the frequency will transiently be infinite: a transient peak in frequency(positive or negative), if any, is instantaneous in electroencephalogram averagingor filtering that the event-related brain potentials required and the underlyingstructure of the event-related brain potentials in the frequency domain cannot beaccounted, for example, by the Wavelet Transform or the Fast Fourier Transformanalysis, because they require that frequency is derived by convolution rather thanby differentiation.However, as I show in the current original research report, one suitablemethod for analyse the instantaneous change in event-related brain potentialsphase and accounted for a transient peak in frequency (positive or negative), if any,in the underlying structure of the event-related brain potentials is the EmpiricalMode Decomposition with post processing (Xie et al., 2014) Ensemble EmpiricalMode Decomposition. KeywordsConsciousness; phenomenology; correlates. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ Acknowledgements Mymother, Maria Dulce. Carlos Simões; Diogo Branco; João Carneiro; João Corujo; Manuel Costa;Manuel Emídio; Sofia Khan; Susana Lourenço.LanCog (Language, Mind and Cognition Research Group), Philosophy Centre,University of Lisbon:Ricardo Santos.My research would not have been possible without their helps.Data available at doi:doi.org/10.5281/zenodo.345092; Data available atZenodo (https://zenodo.org/record/345092#.WLgMNs4pzEp). This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 4 Introduction The relevant computation to the effect of the occipital and left temporal correlatesof the distinction between access and phenomenology (Pereira, 2015) is thecomputation of the high degree of visibility 4-5 assigned by the participants inboth experiments to the correctly identified stimuli (and what there are more inthe second experiment is more incorrect answers than in the first experiment),because to distinguish electrophysiologically the access from phenomenology weneed that access and phenomenology will be cognitively consciousness ofsomething and we need that access be the same for all participants in the twoexperiments (Pereira, 2015: 337-339).To distinguish electrophysiologically the access from phenomenology weneed that access and phenomenology will be cognitively consciousness ofsomething because, for instance, pains are not intentional mental states in thesame sense in which cognitive mental states as beliefs and doubts are intentional:there is nothing in sensation other than being felt. That we have a pain and thenget there and look at it to talk about it is already our cognition to work, but this(cognitive) way of proceeding does not make the sensation itself an intentionalmental state in the same way as when we think about her. Essential to cognitivemental states is that they are intentional without that mark, that of intentionality, This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 5 they wouldn't be the mental states that in fact they are. But pain is another thing:what is essential to them is how we feel them, it is their phenomenology forwithout it, without phenomenology, they wouldn't be the mental states that in factthey are. And at all, mental states as pains are not about anything, they are notintentional they don't represent nothing: although we may represent themcognitively in some way, this is not them to be about something, this is us talkingabout them: this is not them to be cognitions, this is them to be sensations.That is, we compute the results only from those trials that are the same inthe second block of the two experiences.Saying that phenomenology is not reportable is another way to definephenomenology distinctly from access consciousness, but that we already knew:although confusedly when, for example, it is alleged on the basis of the nonreportability the non measurability of phenomenology and thus allegedly thatthere are not electrophysiological correlates of phenomenology different from theaccess.What we know now is what are these electrophysiological correlates ofphenomenology different from the access (Pereira, 2015: 344-350): theelectrophysiologically correlated with the difference (statistically significant)among those trials that are the same in the second block in both experiments forthe same high degree of visibility 4-5 (they also access).The distinct electrophysiological signal correlated with those trials that arethe same in the second block in both experiments is phenomenology to bemeasured (that is, is non reportability to be measured): despite the same highdegree of visibility 4-5 (as despite the same correct answers).The high degrees of visibility are the same 4-5 but, for those trials that are This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 6 the same in the second block in both experiments, the statistical differencebetween the two experiments is significant: because the phenomenology wasmeasured distinctively from the access (behaviorally, there is more incorrectanswers in the first trial of the first block of the second experiment, which isdistinct from the first trial of the first block of the first experiment in which themasks are to be correctly identified but not the targets as in the case of the firstblock of the second experiment. The experimental design only differ in the firsttrial of the first block).Between 300 and 800 ms, the null hypothesis of latency variability betweenexperiments I and II is not rejected: statistically, the variability of the latency didnot significantly differ between the experiments I and II. However the nullhypothesis of variability occipital (Oz) and left temporal (T5) amplitude betweenexperiments I and II is rejected, except for the amplitude variability right temporal(T6) between experiments I and II: statistically, the variability of Oz amplitude andT5 differ significantly between experiments I and II, although the variability ofamplitude T6 between the experiences I and II does not differ significantly (thenull hypothesis of the amplitude variability T6 is accepted).Have more one participant in the second experiment is not computing thehigh degree of visibility 4-5 because these are assigned to the stimulus that theparticipants see (stimulus which is not correctly identified).Notwithstanding, as evoked signal, the change in event-related brainpotentials (ERPs) phase (frequency is the change in phase over time) isinstantaneous, that is, the frequency will transiently be infinite: a transient peak infrequency (positive or negative), if any, is instantaneous in electroencephalogram(EEG) averaging or filtering that the ERPs required and the underlying structure of This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 7 the ERPs in the frequency domain cannot be accounted, for example, by theWavelet Transform (WT) or the Fast Fourier Transform (FFT) analysis, becausethey require that frequency is derived by convolution (frequency are pre-definedand constant over time) rather than by differentiation (without predefiningfrequency and accounted that frequency may vary over time). Participants, Apparatus and stimuli, Procedure, EEG recording, Behavioral data As in Pereira (2015). Twenty two adults with normal vision or corrected to normal, withoutneurological or psychiatric history, ignoring completely the experimentalpurposes.Five participants were excluded dues to excessive EEG artifacts (3) orinsufficient trials (2).The experimental protocol was approved by the doctoral program inCognitive Science, University of Lisbon.Two types of targets: square (1.98 cm side) or diamond (for 45 ° rotation ofthe square).Two types of masks: mask or pseudo-mask. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 8 The width of the mask is 3.05 cm and its inner white portion (RGB 255-255-255) is 8 mmwider than the black (RGB 0-0-0) target stimulus.The width of the pseudo-mask is 3.10 cm and its inner white portion iscircular (2.63 cm diameter).Despite the different sizes, the color black stands in the same area, both inmask and pseudo-mask, and its luminance is identical. This was expected to beimportant to make the masks produce similar ERPs when presented alone.All stimuli are presented on a gray background (RGB 173-175-178).First task: to recognize which of the targets – square or diamond – ispresented.Second task: to evaluate the visibility of targets.The answers are given using the keyboard or the mouse.In the first task, recognition of targets, participants respond if "they seemedto have seen something" by pressing "8" to "yes" and "9" to "no". A negativeresponse completes the trial and starts the next. An affirmative answerconduces the subjects to a screen of sixteen stimuli to signal with the mousewhat seems they have been identified. The position on the screen indicatedby the participant will be recorded informatically as coordinate system <X,Y>.In the second task (evaluation of visibility) we used a Likert scale from "1"to "5": "not visible at all" ("1" key), "barely visible" ("2" key), "visible, butobscure" (key" 3 "), "clear but not quite visible" (key "4 ") and "perfectly clear andvisible" ("5" key).Experiments were held at the Faculty of Psychology in a slightly darkenedsilent room. Participants were seated in a reclining chair at 81.28 centimetersdistance from the 50.8 centimeters monitor. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 9 It is expected that the running of experiment train the volunteer. Thebeginning of the behavioral and EEG recording is unknown to the volunteer.The SuperLab program for Windows from Cedrus, PC compatible,connected to a SVGA color monitor, manages the presentation of stimuli,randomizes their sequence (the trials in each block), the exposure times, therecord of the response, triggers the trigger synchronize with the systemacquisition of physiological signals, MP100 and EEG amplifiers, programAcqKnowledge, both of Biopac.Experiment I.Eight volunteers (aged 18–46 years, M= 22.50, SD=9.562, 7 females).The target and the masks will be presented for 17 ms. The mask (or pseudo-mask) appears 1 ms after the presentation of the target (inter-stimulus interval,ISI, the interval between the termination of the target and the onset of themask). These ISI (1 ms) correspond to 18 ms stimulus-onset asynchrony (SOA,the interval between the onset of the target and the mask) (rounded values).Answers were signaled by mouse on a screen of sixteen stimuli, among whichare the mask and pseudo-mask. Note that the subject not performed a forced-choice task, for example, reading any question either ''Diamond or Square?''or ''Square or Diamond?'', even if counterbalanced across participants (contrastwith, for example, Lau and Passingham 2006).In the second trial, masks were presented for 17 ms, and answers weresignaled by mouse on a screen of sixteen stimuli, among which are the mask andpseudo-mask.Second block. Trial: targets will be presented for 17 ms, and answers weresignaled by mouse on screen of sixteen stimuli, among which are the targets. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 10 Experiment II.Nine volunteers (aged 20–26 years, M= 21.22, SD=2.224, 5 females).The target will be presented for 17 ms (like experiment I), but the mask (orpseudomask) will be presented for 167 ms (unlike experiment I). Note thatin all experiments, targets are always shown for 17 ms and is never replaced, forexample, by a blank screen with the same duration of 17 ms (contrast, forexample, with Del Cul et al. 2007).Unlike experiment I, the target is intercalated between two presentations ofthe mask/pseudo-mask (each, 167 ms): one earlier, paracontrast; the otherafter target, metacontrast.The mask (or pseudo-mask) appears 0 ms before (forward masking) and 1ms after (backward masking) the presentation of the target (inter-stimulusinterval, ISI, the interval between the termination of the target and the onsetof the mask). These ISI (1 ms) correspond to 18 ms stimulus-onset asynchrony(SOA, the interval between the onset of the target and the mask) and to 168 msstimulus-termination asynchrony (STA, the interval between the termination ofthe target and of the mask) (rounded values). Unlike experiment I, the answerwere signaled by mouse on screen of sixteen stimuli, among which are thetargets.In the second trial, like experiment I: masks were presented for 17 ms, andanswers were signaled by mouse on a screen of sixteen stimuli, among whichare the mask and pseudo-mask.Second block, like experiment I. Trial: targets will be presented for 17 ms,and answers were signaled by mouse on screen of sixteen stimuli, among whichare the targets. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 11 The Empirical Mode Decomposition (EMD) with post processing (Xie et al. 2014)and Hilbert-Huang Transform (HHT) Now, we move from the features of the ERP (such as the amplitude and latency ofpeaks) of the Pereira (2015) towards the decomposition of amplitude and to theinstantaneous frequency resulting from this decomposition: the instantaneousamplitude and the instantaneous frequency of event-related changes correlatedwith a contrast in access and with a contrast in phenomenology.Despite that the Wavelet or the Fourier Transform are the methods mostwidely used for analysing the linear (proportionality or additivity) and stationary(the signal, and so the time series representing this signal, has the same mean andvariance throughout) properties of the EEG signal, the EEG signal have nonlinear(nonproportionality or nonadditivity) and non stationary (signal's statisticalcharacteristics change with time) properties.However, one suitable method for analyse the instantaneous change inevent-related brain potentials (ERPs) phase and accounted for a transient peak infrequency (positive or negative), if any, in the underlying structure of the ERPs isthe Empirical Mode Decomposition (EMD) with post processing (Xie et al., 2014)Ensemble Empirical Mode Decomposition (postEEMD).The Wavelet or the Fourier Transform analyse the signal in time-frequency-energy (Wavelet) and in frequency-energy (Fourier) domain without discretefeature extraction (Wavelet, with continuous feature extraction) or withoutdiscrete or continuous feature extraction (Fourier). This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 12 However, the Hilbert-Huang Transform (HHT) analyse the signal in time-frequency-energy domain for feature extraction.For example, either the Fourier functions or the EMD functions areoscillations with zero mean derived from the decomposition of a signal (forexample, ERPs) that when summed together reconstitute the original signal.However, whereas the Fourier functions are called harmonic functionsmeaning that they amplitude and frequency are constant over time, the EMDfunctions are called Intrinsic Mode Functions (IMFs) meaning that they amplitudeand frequency may vary over time.Once the Intrinsic Mode Functions have been extracted and post processing(Xie et al., 2014), the Hilbert-Huang Transform can be used to display theunderlying structure in the amplitude and frequency domain of the grand averageoccipital and left temporal electrical activity characterized in Pereira (2015).These insights may prove to be a useful a guide in helping us move from afocus on the features of the ERP, such as the amplitude and latency of peaks(Pereira 2015), towards a study of the amplitude, instantaneous frequency andenergy structure of event-related changes over time in the EEG.Given the EEG recording in Pereira (2015) with a duration of 1150 ms,defined as 150 ms before the stimulus (baseline) and 1000 ms after its occurrence,there are 16 ERPs correlated with combined target-mask presentations and withisolated presentations of square or diamond and of mask or pseudo-mask: 8 byeach channels, occipital and left temporal.The Empirical Mode Decomposition (EMD) with post processing (Xie et al.,2014) resulted in 56 occipital and 56 left temporal variables (7 postIMFs by eachof the 8 ERPs) in amplitude domain and resulted in 56 occipital and 56 left This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 13 temporal variables in frequency domain with 460 observations each: 230observations (the EEG records duration of 1150 ms) by each of two experiments.In the energy domain, the resulted is 8 occipital and 8 left temporal variables(ERPs) with 14 observations each (7 postIMFs by each of two experiments). Calculated the variance inflation factor (VIF) To evaluate the presumed excessive correlation among variables (i.e., colinearity),we calculated the variance inflation factor (VIF) for each variable by vif_fun.r(beckmw 2013, February 5).If the VIF calculated for each variable is more than 10 (values in the rangeof 5-10 are commonly used as threshold), colinearity is strongly suggested, and thevariable removed.This calculations reduce the 56 variables to 32 in occipital amplitudedomain, reduce the 56 variables to 28 in left temporal amplitude domain, reducethe 56 variables to 51 in occipital frequency domain and reduce the 56 variables to51 in left temporal frequency domain. In energy domain, the calculated varianceinflation factor (VIF) removed 4 variables excessive correlated.Figures 1-2 show the underlying structure in the amplitude domain of thegrand average occipital and left temporal electrical activity correlated with acontrast in access (characterized in Pereira 2015: 340-344), after the calculatedvariance inflation factor (VIF) removed respectively 11 (Oz combined target-maskpresentations) and 14 (T5 combined target-mask presentations) variablesexcessive correlated. The 11 Oz combined target-mask variables excessivecorrelated are postIMF 4 (SquarePseudo,DiamondPseudo), postIMF5 (SquareMask, This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 14 SquarePseudo), postIMF 6 (SquareMask, DiamondMask, DiamondPseudo) andpostIMF 7 (SquareMask, SquarePseudo, DiamondMask and DiamondPseudo). The14 T5 combined target-mask variables excessive correlated are postIMF 3(SquareMask, DiamondMask), postIMF 4 (SquereMask,DiamondMask,DiamondPseudo), postIMF5 (SquareMask, SquarePseudo,DiamondMask, DiamondPseudo), postIMF 6 (SquareMask, SquarePseudo,DiamondMask, DiamondPseudo) and postIMF 7 (DiamondMask ). Figures 3-6 show the underlying structure in the amplitude domain of thegrand average occipital and left temporal electrical activity correlated with acontrast in phenomenology (characterized in Pereira 2015: 344-350), after thecalculated variance inflation factor (VIF) removed respectively 4 (Ozsqua), 4(Ozdiamo), 3 (T5squa) and 5 (T5diamo) variables excessive correlated. The 4Ozsqua isolated target variable excessive correlated are postIMF 4, 5, 6 and 7. The4 Ozdiamo isolated target variable excessive correlated are postIMF 3, 4, 5 and 6.The 3 T5squa isolated target variable excessive correlated are postIMF 4, 5 and 7.The 5 T5diamo isolated target variable excessive correlated are postIMF 3, 4, 5, 6and 7. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 15 Figures 7-8 show the underlying structure in the frequency domain of thegrand average occipital and left temporal electrical activity correlated with acontrast in access (characterized in Pereira 2015: 340-344), after the calculatedvariance inflation factor (VIF) removed respectively 4 (Oz combined target-maskpresentations) and 4 (T5 combined target-mask presentations) variables excessivecorrelated. The 4 Oz combined target-mask variables excessive correlated arepostIMF 7 (SquareMask, SquareMask, DiamondMask and DiamondPseudo). The 4T5 combined target-mask variables excessive correlated are postIMF 6(SquareMask), postIMF 7 (SquareMask), postIMF 7 (DiamondMask andDiamondPseudo). This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 16 Figures 9-12 show the underlying structure in the frequency domain of thegrand average occipital and left temporal electrical activity correlated with acontrast in phenomenology (characterized in Pereira 2015: 344-350), after thecalculated variance inflation factor (VIF) removed 1 (postIMF 6 T5squa) variablesexcessive correlated: any OzSquare, Ozdiamo or T5diamo variables is removedbecause neither variable is excessive correlated. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 17 Partial least squares regression (PLSR): the minimal root mean squared error ofprediction (RMSEP) If we set 59 as the seed, the partial least squares regression (PLSR) (Wold 2001,Martens 2001, Mevik and Wehrens 2007), cross-validated using 10 randomsegments, returned the postIMF 3 (combinexpOzDiamondPseudo) as the minimalroot mean squared error of prediction (RMSEP) for Oz instantaneous amplitude(23 variables) and the postIMF 2 (combinexpT5DiamondPseudo) as the minimalroot mean squared error of prediction (RMSEP) for T5 instantaneous amplitude(19 variables).The minimal postIMF that least erroneously explains the variabilitybetween the two experiments in Oz instantaneous amplitude is predictably thepostIMF 3 combined Diamond Pseudo. That is, the minimal postIMF instantaneousamplitude associated (with less error of prediction) to the variability between thetwo experiments in Oz instantaneous amplitude is, after partial least squaresregression validation, postIMF 3 combined Diamond Pseudo. The postIMF 3combined Diamond Pseudo is the Oz instantaneous amplitude minimal value thatwe can use to measure with less error of prediction the propagation of theremaining Oz instantaneous amplitude values around the variability between thetwo experiments. (Fig. 13.) This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 18 An independent-sample t-test was conducted to compare postIMF 3combined Diamond Pseudo (Ozp3cDP) between the two experiments in Ozinstantaneous amplitude. Equal variances not assumed, there was a significantdifference in the postIMF 3 combined Diamond Pseudo Oz instantaneousamplitude for experiment II (M= 250.08, SD= 221. 24) and experiment I (M=141.85,SD = 116. 99), t (347.796)= 6.559, p < 0.001, 95% CI [75.78, 140.69], g [ 95 % CI] =0.61 [ 0.42 , 0.8 ]. The Common Language Effect Size (CLES) indicates that thechance that for a randomly selected pair of Ozp3cDP instantaneous amplitudevalues the Ozp3cDP instantaneous amplitude values from experiment II is higherthan the Ozp3cDP instantaneous amplitude values from experiment I is 66.7% (DelRe, 2013).The minimal postIMF that least erroneously explains the variabilitybetween the two experiments in T5 instantaneous amplitude is predictably thepostIMF 2 combined Diamond Pseudo. That is, the minimal postIMF instantaneousamplitude associated (with less error of prediction) to the variability between thetwo experiments in T5 instantaneous amplitude is, after partial least squaresregression validation, postIMF 2 combined Diamond Pseudo. The postIMF 2 This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 19 combined Diamond Pseudo is the T5 instantaneous amplitude minimal value thatwe can use to measure with less error of prediction the propagation of theremaining T5 instantaneous amplitude values around the variability between thetwo experiments. (Fig. 14.) An independent-sample t-test was conducted to compare postIMF 2combined Diamond Pseudo (T5p2cDP) between the two experiments in T5instantaneous amplitude. Equal variances not assumed, there was a significantdifference in the postIMF 2 combined Diamond Pseudo T5 instantaneousamplitude for experiment II (M= 231.50 SD= 193.05) and experiment I (M=148.88,SD = 116.23), t (375,748)= 5,561, p < 0.001, 95% CI [53.40, 111.84], g [ 95 % CI] =0.52 [ 0.33 , 0.7 ]. The Common Language Effect Size (CLES) indicates that thechance that for a randomly selected pair of T5p2cDP instantaneous amplitudevalues the T5p2cDP instantaneous amplitude values from experiment II is higherthan the T5p2cDP instantaneous amplitude values from experiment I is 64.28%(Del Re, 2013).If we set 59 as the seed, the partial least squares regression (PLSR), cross-validated using 10 random segments, returned the postEEMD 1 (OzMask) as the This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 20 minimal root mean squared error of prediction (RMSEP) for Oz instantaneousfrequency (40 variables) and the postIMF 5 (T5Mask) as the minimal root meansquared error of prediction (RMSEP) for T5 instantaneous frequency (43variables).The minimal postIMF that least erroneously explains the variabilitybetween the two experiments in Oz instantaneous frequency is predictably thepostIMF 1 Mask. That is, the minimal postIMF instantaneous frequency associated(with less error of prediction) to the variability between the two experiments in Ozinstantaneous frequency is, after partial least squares regression validation,postIMF 1 Mask. The postIMF 1 Mask is the Oz instantaneous frequency minimalvalue that we can use to measure with less error of prediction the propagation ofthe remaining Oz instantaneous frequency values around the variability betweenthe two experiments. (Fig. 15.) An independent-sample t-test was conducted to compare postIMF 1 Mask(Ozp1M) between the two experiments in Oz instantaneous frequency. Equalvariances not assumed, there was a significant difference in the postIMF 1 Mask Ozinstantaneous frequency for experiment II (M= 0.29, SD= 0.14) and experiment I This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 21 (M=0.23, SD = 0.15), t (457.061)= 4.737, p < 0.001, 95% CI [0.03, 0.09], g [ 95 % CI]= 0.44 [ 0.26 , 0.63 ]. The Common Language Effect Size (CLES) indicates that thechance that for a randomly selected pair of Ozp1M instantaneous frequency valuesthe Ozp1M instantaneous frequency values from experiment II is higher than theOzp1M instantaneous frequency values from experiment I is 62.24% (Del Re,2013). The minimal postIMF that least erroneously explains the variabilitybetween the two experiments in T5 instantaneous frequency is predictably thepostIMF 5 Mask. That is, the minimal postIMF instantaneous frequency associated(with less error of prediction) to the variability between the two experiments in T5instantaneous frequency is, after partial least squares regression validation,postIMF 5 Mask. The postIMF 5 Mask is the T5 instantaneous frequency minimalvalue that we can use to measure with less error of prediction the propagation ofthe remaining T5 instantaneous frequency values around the variability betweenthe two experiments. (Fig. 16.) An independent-sample t-test was conducted to compare postIMF 5 Mask(T5p5M) between the two experiments in T5 instantaneous frequency. Equal This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 22 variances not assumed, there was a significant difference in the postIMF 5 Mask T5instantaneous frequency for experiment I (M=0.017, SD = 0.007) and experiment II(M= 0.0129, SD= 0.0046), t (440.573)= 9.011 p < 0.001, 95% CI [ 0.0034,0.0053], g[ 95 % CI] = 0.84 [ 0.65 , 1.03 ]. The Common Language Effect Size (CLES) indicatesthat the chance that for a randomly selected pair of T5p5M instantaneousfrequency values the T5p5M instantaneous frequency values from experiment I ishigher than the T5p5M instantaneous frequency values from experiment II is72.35% (Del Re, 2013).The calculated minimal value that we can use to measure with less error ofprediction the propagation of the remaining values around the variability betweenthe two experiments reduced the number of variables in instantaneous amplitudefrom 32 (of 56, after variance inflation factor calculations) to 23 (Oz) and from 28(of 56, after variance inflation factor calculations) to 19 (T5) and reduced thenumber of variables in instantaneous frequency from 51 (of 56, after varianceinflation factor calculations) to 40 (Oz) and from 51 (of 56, after variance inflationfactor calculations) to 43 (T5).Notwithstanding, what variables are important for the variability betweenthe two experiments remained to be assessed. Partial least squares regression (PLSR): significance multivariate correlation (sMC)statistic Given the calculated minimal value that we can use to measure with lesserror of prediction (namely, 23 variables in Oz instantaneous amplitude, 19variables in T5 instantaneous amplitude, 40 variables in Oz instantaneous This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 23 frequency and 43 variables in T5 instantaneous frequency) the propagation of theremaining values around the variability between the two experiments, whichvariables are important for the variability between the two experiments areassessed by significance multivariate correlation (sMC) statistic (Afanador et al.,2016 and, e.g., Thanh et al., 2014) of the partial least squares regression (PLSR)results (figs. 13-16), cross-validated using 10 random segments (setting 59 as theseed). In other words, which variables are important for the variability betweenthe two experiments are assessed by comparing the ratios between the variable-wise Mean Squared Errors (MSE) and the mean squared of its residuals to an F-testwith 1 and N 2 degrees of freedom (the cut-off is based on the F-test, becauseappeared that the cut-off based on the mean was influencing negatively thepredictions): the variables that exceed the F-test threshold are selected.If we set 59 as the seed, the significance multivariate correlation (sMC)statistic, with a correction of 1st order auto-correlation in the residuals, "out-of-bag" (OOB) validation and with 1000 cross-validation bootstrap samples, selectedthe following variables as important for the variability between the twoexperiments in Oz and T5 instantaneous amplitude and in Oz and T5 instantaneousfrequency.Related to Oz instantaneous amplitude, the 4 variables postIMF 6SquarePseudo, postIMF 7 diamo, postIMF 4 SquareMask, postIMF 4 DiamondMask,empirical decomposed and post processing (Xie et al., 2014) from Oz event-relatedchanges (Pereira, 2015), are selected as important for the variability between thetwo experiments in instantaneous amplitude. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 24 Related to T5 instantaneous amplitude, the 2 variables postIMF 7DiamondPseudo and postIMF 7 SquarePseudo, empirical decomposed and postprocessing (Xie et al. 2014) from T5 event-related changes (Pereira, 2015), areselected as important for the variability between the two experiments ininstantaneous amplitude.Related to Oz instantaneous frequency, the 6 variables postIMF 7Pseudomask, postIMF 6 SquarePseudo, postIMF 5 SquarePseudo, postIMF 5SquareMask, postIMF 6 DiamondPseudo and postIMF 7 diamo, empiricaldecomposed and post processing (Xie et al. 2014) from Oz event-related changes(Pereira, 2015), are selected as important for the variability between the twoexperiments in instantaneous frequency.Related to T5 instantaneous frequency, the 8 variables postIMF 7 squa,postIMF 7 Mask, postIMF 5 SquarePseudo, postIMF 5 diamo, postIMF 5SquareMask, postIMF 4 diamo, postIMF 4 SquarePseudo and postIMF 5DiamondMask, empirical decomposed and post processing (Xie et al., 2014) fromT5 event-related changes (Pereira, 2015), are selected as important for thevariability between the two experiments in instantaneous frequency.The repeated measures analysis of variance (ANOVA) with the experiment Iand experiment II (Pereira, 2015) as a between-subjects factors and the postIMFvariables selected as important by significance multivariate correlation (sMC)statistic as a within-subject factors gave the following significant (Greenhouse-Geisser correction for violations of the sphericity) results for Oz instantaneousamplitude [F(1.197,548.082)= 146.612, p < 0.001, ηp2 = 0.24249, 90% CI [0.96 ,1.29], ηG2 = 0.14940] and for T5 instantaneous amplitude [F(1, 458)= 3710.346, p< 0.001, ηp2 = 0.89012, 90% CI [5.33 , 6.02], ηG2 = 0.51299]. For Oz and T5 This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 25 instantaneous frequency, the repeated measures ANOVA results are respectively[F(3.111,1424.755)= 73.586, p < 0.001, ηp2 = 0.13843, 90% CI [0.64 , 0.96], ηG2 =0.08082] (Oz) and [F(2.493,1141.681)= 441.582, p < 0.001, ηp2 = 0.49087, 90% CI[1.77 , 2.14], ηG2 = 0.42934] (T5) (Lakens, 2013).The statistically significant contrast in the variability of intrinsic modefunctions, empirical decomposed and post processing (Xie et al., 2014) from event-related changes (Pereira 2015), between the two experiments correlated with acontrast in access is for the instantaneous amplitude within the 3 variablespostIMF 6 SquarePseudo, postIMF 4 SquareMask, postIMF 4 DiamondMask (Oz)(fig. 17) and within the 2 variables postIMF 7 DiamondPseudo and postIMF 7SquarePseudo (T5) (fig. 18). Related to instantaneous frequency, the statistically significant contrast inthe variability of intrinsic mode functions between the two experiments correlatedwith a contrast in access is within the 4 variables postIMF 6 SquarePseudo,postIMF 5 SquarePseudo, postIMF 5 SquareMask and postIMF 6 DiamondPseudo(Oz) (fig. 19) and within the 4 variables postIMF 5 SquarePseudo, postIMF 5SquareMask, postIMF 4 SquarePseudo and postIMF 5 DiamondMask (T5) (fig. 20). This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 26 The statistically significant variability between the two experimentscorrelated with a contrast in phenomenology is for the instantaneous amplitudewithin the 1 variables postIMF 7 diamo (Oz) (fig. 21). However, none variable, empirical decomposed and post processing (Xie etal., 2014) from T5 event-related changes (Pereira, 2015), is within selected asimportant for the variability in instantaneous amplitude between the twoexperiments correlated with a contrast in phenomenology, as it is selected asimportant for the variability in T5 instantaneous frequency (following 2ndparagraph).Remind that the trials that are the same in the second block in bothexperiments for the same high degree of visibility 4-5 (they also access) and for thesame correct answers (stimulus's discrimination don't contrast in correct and This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 27 incorrect responses between the two experiments) are the isolated presentationsof square or diamond and of mask or pseudo-mask.Related to instantaneous frequency, the statistically significant contrast inthe variability of intrinsic mode functions between the two experiments correlatedwith a contrast in phenomenology is within the 1 variables postIMF 7 diamo (Oz)(fig. 22) and within the 3 variables postIMF 7 squa, postIMF 5 diamo, postIMF 4diamo (T5) (fig. 23). These intrinsic mode functions explain the variability of the occipital andleft temporal electrical activity co-occurring with a contrast in access distinctlyfrom the variability of the occipital and left temporal electrical activity co-occurring with a contrast in phenomenology (Pereira, 2015) with the accuracythat, related to the left temporal (T5) electrical activity co-occurring with acontrast in phenomenology, the distinct electrophysiological signal is in theinstantaneous frequency domain but don't in T5 instantaneous amplitude domain. This manuscript version is made available under the CC BY 4.0 licensehttps://creativecommons.org/licenses/by/4.0/ 28 ReferencesAfanador, Nelson Lee, Tran, Thanh and Blanchet, Lionel (2016). Package 'mvdalab'.R package version 1.0.beckmw (2013, February 5). 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