stimulus and 1-pentine as unpleasant, and to confirm the previousresults. Participants were 20 university students (17 men, 3 women;23.6 ± 1.9 years) with normal olfactory function and taking nomedication. They were requested to refrain from alcohol and coffeefor 12 hr prior to the experiment. The study was performed inaccordance with 1964 Declaration of Helsinki, and was approved bythe Shizuoka University Research Ethics Committee.Results and discussion: The results showed that the P3 latencies wereshorter in 70%participants (14 out or 20) and P3 amplitudeswere loweralso in 70% participants for unpleasant olfactory stimulus. In conjunc-tion with the previous report, these findings demonstrate thatunpleasant smell shortens the latency of P3 component, which meansthat unpleasant stimulation accelerates the auditory informationprocessing in our brain.

doi:10.1016/j.ijpsycho.2014.08.804

Do color surroundings affect the pain-related somatosensoryevent-related potentials (SEPs) to painful electrical stimulus?

Kenzo Konishia, Midori Hashimotob, Ippei Umekia, Seiya Taharaa,Yushi Katoa, Jun-ichi AkiyamaaaKibi International University, JapanbHiroshima University, Japan

Subjective pain is decreased by distracting attention or involvingdistraction task (eg. Yamasaki et al., 2000; Sato and Ohnishi, 2012).However, there are only a few studies investigating the effects ofsurroundings to the subjective pain. The aim of this study is toinvestigate the effect of color surroundings to the subjective painusing pain-related somatosensory event-related potentials (pain-related SEPs).

Eleven undergraduate students participated in this experiment.Stimulus was painful electrical stimulation applied to the right mediannerve. Prior to the experiment, participants' pain-stimulus thresholdsweremeasured bymethod of adjustment. Therewere five kinds of colorsurroundings. They were white, yellow, green, blue and red. Colorsurroundings were made by wearing goggles with color cellophanepapers. For white, sheets of plastic bag were used. Brightness wasadjusted equally by subjective estimation of three members amongexperimenters. Participants received all color conditions with counter-balanced order, two times for each color. After wearing goggles,participants sat on the chair comfortably putting their upper half ofthe body into the small chamber lighted up equally, and receivedpainful electrical stimulation. In one trial, sixty stimuli were presentedevery 1000 ms with 200-ms duration. EEG was recorded from C3 andC4, and ERPs were calculated by averaging EEGs from 100 ms beforestimulus onset to 400 ms after stimulus onset. After recording EEGs ineach color surrounding condition, subjective pain estimation was alsomeasured by VAS (Visual analogue scale).

Three ERP components, P175, N240 and P295 were observedbilaterally. Mean ERP amplitudes including these peak latencies werecompared among color surrounding conditions. As the results, P175amplitudes were more positive in the blue condition than in thewhite and yellow conditions at F4 site. And more, P295 amplitudeswere more positive in the green condition than in the white and redconditions at F4 site. These results indicate that in the blue and greencondition, attentional resources were not so distributed to the painstimulus. This suggests these colors alleviate the pain sensation. Thisidea is consistent with VAS data, that is, in blue and green conditions,VAS values were smaller than in another color conditions.

doi:10.1016/j.ijpsycho.2014.08.805

Averaging number in MMN calculations suitable forclinical application

Kazuko Kanno, Shuntaro Itagaki, Takashi Matsuoka, Tetsuya Shiga,Michinari Nozaki, Satoko Asano, Yusuke Osakabe, Masayuki Hikita,Norikatsu Itoh, Hirooki YabeFukushima Medical University School of Medicine, Japan

Background: Mismatch negativity (MMN) discovered by Näätänen,et al. (1978) is a component of the event-related potentials to auditorystimuli. MMN is elicited by any frequent change in a repetitive sequenceof sounds regardless of the participant's attention. MMN may beestablished as a clinical measure to evaluate cognitive function in thefuture, but its reliability must first be confirmed. We investigated theappropriate number of stimuli necessary to achieve reliable MMNwaveforms while minimizing patient burden.Method: Participants were 16 healthy men (age range, 25–45 years).The auditory stimuli were delivered via left earphone. The deviantstimuli (1000 Hz, 75 dB, 50 ms) were presented at a probability of 20%,while the standard stimuli (1000 Hz, 75 dB, 100 ms) were presented ata probability of 80%. Synchronous onset asynchrony was 500 ms.During sound stimuli, participants were viewing self-selective silentvideo. Electroencephalography (EEG) was recorded from electrodesapplied 4 sites (Fz, Cz, andmastoids) and referenced to a nose electrode.We recorded the EEG in response to 12,000 stimuli andmade the grandaverage waveform adding each 2000 stimuli.Results: MMN was elicited as peak negativity at midline (Fz, Cz)while as peak positivity at mastoids within the 150–200 ms latencyrange from the stimulus onset. Approximately half of the participantskept the reliable waveforms after 4000 stimuli and the remaininghalf of the participants kept the reliable waveforms after 6000stimuli. We were able to make a healthy control MMN waveform.Conclusion:However the appropriate number of stimuli is 4000 or 6000,it should be decided in consideration of a balance with the fatigue degreeof participants and the reliability of the waveforms. This study is the firststep to standardize MMN procedure to evaluate individual cognitivefunction.

doi:10.1016/j.ijpsycho.2014.08.806

Cortical regions involved in integration of visual information ofpoint-light walker and background motion velocity

Tamaki MiyamotoGraduate School of Medicine, Hokkaido University, Japan

Background: In most previous studies, point-light walkers (PLW) havebeen presented against solid color backgrounds. However, a walker isusually seen against a background visual scene that provides additionalvisual input. As a viewer tracks a walker, the visual world streams in adirection opposite to the walking direction around the walker in apattern of background visual motion (BVM). Our previous studydemonstrated that cortical areas show changes in neural activitydepending on the specific combination of directions of PLWs and BVMs,suggesting integration of their visual information. This study specificallyaddressed effects of velocity of BVM against a PLW. Therefore, fMRI wasused to investigate cortical regions that showdifferences in activation atcombinations of PLWs and different velocities of BVM.Methods: Subject: Subjects were 22 healthy adults. Study proce-dures were performed in strict compliance with the Declaration ofHelsinki and with local ethical committee approval. All subjectsprovided written informed consent.Stimulus: The stimulation field was subtended 4° × 4°. A PLWconsisting of 11 white dots (0.16° diameter) was presented as walking

International Journal of Psychophysiology 94 (2014) 120–261 195

on a treadmill in the frontoparallel plane. Scrambled motions (SM)were made by randomizing the spatial locations of each point-light ofthe PLW. BVMs consisted of 128white dots (0.06° diameter), moving ina direction opposite to the PLW walking direction with one of threevelocities according to the PLW walking velocity: quarter, equal, andfourfold. Through a mirror attached to a head coil in an MRI scanner,subjects viewed the screen displaying visual stimuli.Procedure: Sixconditions were examined in an event-related fMRI paradigm as 2(PLW or SM) × 3 BVM velocity. Subjects were asked to press a buttonaccording to judgment of the walking directions of both PLWs and SMs.The fMRI time series were obtained using a 1.5 T MRI system. The fMRIdata were analyzed using SPM8.Results: 2 (PLW or SM) × 3 (velocity) ANOVAs for fMRI datashowed significant interactions in the left anterior superiortemporal sulcus (aSTS). Subsequent ANOVA results revealed that amain effect of velocity was significant among conditions with PLWin the left aSTS. Subsequent t-tests revealed that activation under“equal” and “fourfold” conditions with PLW were significantlygreater than those under “quarter” conditions with PLW in the leftaSTS.Discussion and conclusion: These findings provide evidence forintegration of the walking velocity of PLW and velocity of BVM in theaSTS.

doi:10.1016/j.ijpsycho.2014.08.807

The role of different class neurons of cat visual cortexin the local synchronization

Evgeniya Belova, Irina IschenkoA.B. Kogan Research Institute of Neurocybernetics, Southern FederalUniversity, Russia

Synchronized neuronal activity is considered to be related to amechanism for visual feature binding. The role of different class neuronsin the synchronization is not fully understood. The goal of the presentstudy was to investigate the local synchronized neuronal activity andthe role of different class neurons in neural synchrony. The neurons ofcat visual cortex (149 cells)were recorded extracellularly in response tovisual stimuli. Sinusoid gratings were used for visual stimulation. Theneurons were classified based on a wide variety of electrophysiologicalproperties and compared with well-known functional classes ofneurons: Fast Spiking (FS), Fast Repetitive Bursting (FRB), RegularSpiking (RS), Intrinsically Bursting (IB). We estimated the strength ofthe synchronization between the pairs of neurons using cross-correlation methods. Thirteen pairs of neurons that were strongly orat least moderately synchronized had a shifted peak in the cross-correlogram of 2–10 ms. The neurons with short-duration of the spikeand unimodal distributions of interspike interval histograms withspikes at modal frequencies of 300–500 Hz were classified as FS cells(17 cells). FRB neurons (36 cells) with narrow spikes and bimodaldistributions of interspike intervals generated bursts of spikes withintraburst frequencies of 330–500 Hz. Thewide-spike cells with RS typeof activity were characterized by unimodal distributions of interspikeintervals with an average modal frequency of 88.5 Hz (64 cells).Neurons with wide spikes and bimodal interspike intervals wereclassified as IB neurons (32 cells).Wemeasured orientation tuningwithrespect to firing rate and selected 57 pairs of cells with similar preferredorientations. It was revealed that activity of these neurons was stronglyor moderately synchronized in response to preferred orientations. Theneurons with short spike and FRB type of activity were the first thatwere engaged in the synchronization. The cells with wide spike and RSor IB type of activity followed the FRB and FS neurons. The results of theinvestigation give the evidence that FRB neurons initiate the process of

forming the pattern of synchronous neural activity of functional groupsor cell assemblies to process incoming sensory information.

doi:10.1016/j.ijpsycho.2014.08.808

Specific “vision deficit”: Description and primary analysis

Gennady S. VoronkovThe Ì.V. Lomonosov Moscow State University, Russia

Background: The phenomenon, referred here as specific “vision deficit”(SVD), is broadly known in ophthalmology. However, the generallyaccepted description and explanation of its nature are absent. SVD hasbeen detected in all “patients”, including those with normal vision. Itbecomes evident upon a strong narrowing of the monocularly visiblefield by means of the ophthalmic set diaphragm. SVD appears as atranslucent web-like patch which covers much of the visible field andprevents to clearly see the letters of the ophthalmic table.SVD properties: (1) In SVD patch, two pictures appeared simulta-neously, stable and unsteady. (2) The stable picture defines a generalpatch form and can contain stable inclusions as whitish “vesicles”;the patch form remains unchanged after winking and the vesiclessave their specific location for the given eye, constant through theresearch sessions. (3) The unsteady picture is the various-size-and-form dark and whitish inclusions, appearing after winking, comedownwards or remain but disappear after the following winking.(4) The SVD patch and its all stable and dynamic inclusions do notshift with a gaze relative to the background objects visible throughthe diaphragm. (5) But they are displaced in the background alongwith the diaphragm displacement when the gaze is fixed at someobject of the background. (6) They do not turn round togetherwith diaphragm at its rotation. (7) But they (and their movementdirection) turn round together with inclination of the head to theside. (8) The SVD patch is seen simultaneously in all diaphragms ifseveral of them are located not far from one another. Herewith eachSVD patch is similar to those created by the rest diaphragms.(9) There is an observation that SVD patch is more expressed in theeye with a greater vision deficit.Analysis: Properties 3 and 7 are not consistent with the exclusivelyholographic hypothesis of SVD patch origin. Property 4 is not consistentwith the hypothesis about SVD patch inclusions as manifestations ofinclusions and defects on the cornea, lens, vitreous or on retina. The SVDproperties suggest the complex SVD patch nature. We discuss thepossibility to create a partial SVD picture on retina by light reflectedfrommirror elements which are supposedly identified as such betweenthe receptor and vascular layers. We introduce the notions “stabilizedretina image”, “constant screen” and “competitive relations” betweenthe retinotopic projections creating the vision sensations.

doi:10.1016/j.ijpsycho.2014.08.809

Psychophysiological analysis of multidimensional structureof brightness perception in normal and altered statesof consciousness

Andrey A. Kiselnikov, Ivan S. Pozdniakov, Anastasiya O. Myasnichenko,Alexander V. Vartanov, Janna M. Glozman, Stanislav A. Kozlovskiy,Maria M. PyasikLomonosov Moscow State University, Russia

Background: Application of multidimensional scaling to studyingcolor and brightness perception has solid history but complex brain-

International Journal of Psychophysiology 94 (2014) 120–261196