role in suppressing distractive information. We tested these hypothesesand tried to elucidate their essential neuronal mechanisms. We simu-lated a neural network containing a sensory network (SN) and a defaultmode network (DMN). The SN consisted of cell assemblies. Each cellassembly, comprising principal cells, GABAergic interneurons and glialcells, responded to one specific sensory feature. A single cell assembly,comprising principal cells and GABAergic interneurons, constituted theDMN. Principal cells of the DMN showed intrinsic high level firingactivity during the ongoing-spontaneous time period prior to sensorystimulation (without sensory stimulation). We let the SN carry outa simple perceptual task: detection of sensory feature stimuli. DuringDMN activation, glial cells of the SN were hyperpolarized, by which glialmembrane transporters imported GABA molecules from the extracellu-lar space and decreased ambient GABA concentration. Ambient GABAmolecules acted on extrasynaptic GABA receptors. Hence, the decrease ofambient GABA concentration reduced inhibitory current in P cells of theSN. This depolarized the P cells below firing threshold and enhancedtheir responsiveness to sensory feature stimulus. During the stimuluspresentation period, the SN inhibited P cells of theDMNand causedDMNdeactivation. This depolarized glial cells, by which the glial membranetransporters exported GABA molecules into the extracellular spaceand increased ambient GABA concentration. The increase of ambientGABA concentration augmented inhibitory current in P cells of the SN ina global manner (i.e., across cell assemblies). Interestingly, the firingactivity of stimulus-relevant P cells was maintained provided that ahypothetical interneuron-to-glia signaling worked. This resulted ininhibiting the stimulus-irrelevant P cells while maintaining the stimu-lus-relevant P cell activity. We suggest that the DMN may have roles inimproving sensory responsiveness and suppressing distractive informa-tion, reflected in the decrease in stimulus-irrelevant P cell activity, inorder to achieve the best perceptual performance. The GABAergic glio-transmission mechanism may coordinate the effects of DMN activationand deactivation in sensory information processing.

doi:10.1016/j.ijpsycho.2014.08.780

Oral Session 3

Emotion and decision making

Chair: Márk Molnár (Hungary)

Risky and cautious choice-making — Age-dependent changes offeedback related negativity in a gambling task

Márk Molnár, Zsófia K. Kardos, Roland Boha, Bálint File, Brigitta TóthInstitute of Cognitive Neuroscience and Psychology, Research Centre forNatural Sciences, Hungarian Academy of Sciences, Budapest, Hungary

Choice behavior is influenced bymotivation in which processing offeedback stimuli plays an important role. The neural systems behindreward and punishment that guide these processes are more or lessclear but less is known how these are modified by aging. The aim ofthe present study was to analyze the age-related differences in risk-taking behavior by using electrophysiological methods. 25 young(mean age: 21.76 yrs) and 23 elderly (mean age: 66.87 yrs) partici-pated in the study. The subjects performed a monetary gambling taskin which they had to choose between low or high stakes both withpossible gain or lose outcomes. The monetary difference between thehigh and low stake conditions was twofold. The results (gain or loss)were indicated by an outcome stimulus (green or red light). No timepressure was applied. The EEG was recorded by 64 electrodes and thefeedback related potentials (FRPs) evoked by the outcome stimuliwere analyzed. It was found that in both age groups high losses

were followed by opting for higher stakes. Of the FRPs the negativecomponent (feedback related negativity [FRN], latency: approx.250 ms) was analyzed. The amplitude of the FRN was much largerevoked by the “loss signal” than those elicited by the “gain signal” inthe young, irrespective of whether the stake was high or low. The FRNcomponent was also seen in the elderly but with lower amplitude andwith no conspicuous difference between conditions. The scalpdistribution of the FRN was different in the two age groups. Time-frequency analysis revealed a conspicuous difference between gainand lose conditions depending upon age. In conclusion, whereas overtbehavioral differences were not obvious between age groups in thecondition investigated, analysis of FRPs revealed that the processesreflected by FRN were strikingly different in the young comparedto the elderly. Characteristics of the FRN corresponded to errorassessment but were obvious only in the young. It appears that theevaluation of feedback stimuli is markedly less efficient in the elderly.

Grant support: OTKA 104332.

doi:10.1016/j.ijpsycho.2014.08.781

Decision-making in individuals with intellectual disabilitiesrevealed by near infrared spectroscopy

Hiroaki Shojia, Ayano Mizokoshib, Taichi Hirayamac, Hisaki OzakiaaCollege of Education, Ibaraki University, JapanbGraduate School of Education, Ibaraki University, JapancGraduate School of Science and Engineering, Ibaraki University, Japan

Previous studies have shown that individuals with intellectualdisabilities have difficulty in utilizing information from two differentdimensions for decision-making. For instance, individuals with intel-lectual disabilities tended to choose randomly or with only a singledimension (time or money) in the temporal discounting (TD) task,which is required to choose between a small immediate reward and alarge delayed reward. However, neural correlates of their behavioralcharacteristics on decision-making have not been clarified. Therefore,we examined cerebral activity during decision-making in individualswith intellectual disabilities using near-infrared spectroscopy (NIRS).Five adolescents with intellectual disabilities (mean age 17.6 years) and15 normal adults (mean age 22.9 years) participated in this experiment.In the TD task, two apple images were presented at the left and rightside of the screen. Simultaneously, sale money and harvest day waspresented on the bottom of the images. In one side of the screen, theamount of money was relatively expensive but delayed harvest couldfail to get the apple (high risk). In the opposite side, harvest was surelypossible but sale money was relatively inexpensive (low risk). In eachtrial, participants were asked to select by touching either side of thescreen. 4 sequential trials for each 5 secondswere conducted in the taskperiod. Feedback on a total amount of money was also presented for2 seconds after the 4th trial. 20-second rest period and 22-second taskperiod were repeated twice for NIRS measurement. NIRS was recordedfrom 16 channels in frontal area (OEG-16, Spectratech). Mean values ofOxy-Hb at each channel was compared between 5-second before and22-second during the task period. In normal adults, response patternbased on trade-off between reward value and time delaywas observed.Therefore,waveforms of bloodflowwere averaged over trials indicatingsuch a pattern. As a result, the concentration changes in Oxy-Hb duringthe task period significantly increased in left dorsolateral prefrontalcortex (DLPFC). In individualswith intellectual disabilities, therewas noresponse pattern based on the trade-off in every trial. However,increment of Oxy-Hb in left DLPFCwas observed during the task periodin two individuals with intellectual disabilities. Focusing on theirbehavioral data, their response was decided by utilizing informationfrom two different dimensions although it was not rational trade-off.

International Journal of Psychophysiology 94 (2014) 120–261186