Observing Erotic Videos with Heterosexual Content Induces Different Cerebral Responses in Homosexual and Heterosexual Men.

To determine the cerebral functionality associated with the perception and processing of erotic stimuli in men with different sexual orientation, this work evaluated the electroencephalographic activity (EEG) from several cortical areas, as well as subjective arousal in homosexual and heterosexual men during observation of an erotic film with heterosexual content. The heterosexual men rated the erotic video with higher general and sexual arousal than the homosexual participants. During observation of the neutral and erotic videos, both groups showed a decreased amplitude of the alpha band in prefrontal and parietal cortices, indicating increased attention. When watching the erotic video, the homosexual men showed an increased amplitude of the theta and fast bands only in the prefrontal cortex, which could be related to the cognitive processing of the erotic stimulus. These EEG results should broaden our knowledge of the cortical mechanisms related to the different perception and processing of erotic stimuli in men with different sexual orientations.

Observing Erotic Videos With Heterosexual Content Induces Different Cerebral Responses in Homosexual and Heterosexual Men.

To determine the cerebral functionality associated with the perception and processing of erotic stimuli in men with different sexual orientation, this work evaluated the electroencephalographic activity (EEG) from several cortical areas, as well as subjective arousal in homosexual and heterosexual men during observation of an erotic film with heterosexual content. The heterosexual men rated the erotic video with higher general and sexual arousal than the homosexual participants. During observation of the neutral and erotic videos, both groups showed a decreased amplitude of the alpha band in prefrontal and parietal cortices, indicating increased attention. When watching the erotic video, the homosexual men showed an increased amplitude of the theta and fast bands only in the prefrontal cortex, which could be related to the cognitive processing of the erotic stimulus. These EEG results should broaden our knowledge of the cortical mechanisms related to the different perception and processing of erotic stimuli in men with different sexual orientations.

Alpha electroencephalographic activity during rapid eye movement sleep in the spider monkey (Ateles geoffroyi): An index of arousal during sleep?

There is evidence that some animal species have developed physiological and behavioral mechanisms to monitor potential predatory threats during rapid eye movement sleep (REMS). Nevertheless, it has not been reported in arboreal primates. The present study analyzed the sleeping postures, as well as the electromyographic and electroencephalographic (EEG) activities during three conditions: REMS, non-REMS (N-REMS), and wakefulness in spider monkeys. The study included six monkeys, whose EEGs were recorded at the O1-O2, C3, C4, F3, and F4 derivations to analyze relative power (RP) and interhemispheric, intrahemispheric, frontoposterior, and central-posterior coherence of frequency bands, which has been considered an index of arousal states. The bands analyzed were theta (4.0-7.0 Hz), alpha1 (8.0-10.5 Hz), alpha2 (11.0-13.5 Hz), and beta (14.0-30.0 Hz). Spider monkeys adopt a vertical posture during sleep, and in REMS a lack of muscular atonia was observed. The RP of the alpha bands at O1-O2 was higher during REMS than that during wakefulness, N-REMS1, and N-REMS2. At the C3 derivation, the RP of alpha1 was higher during REMS than that during N-REMS2. The RP of both alpha bands at the F4 derivation was higher during REMS than that during wakefulness, whereas REMS was characterized by a higher coherence between the F3 and O1-O2 derivations of the alpha2 band. These prevalences and the higher coherence of alpha bands during REMS could represent a correlate of behavioral traits and activated cortical areas related to a possible arousal state in spider monkeys while sleeping.

EEG activity during the spatial span task in young men: Differences between short-term and working memory.

Short-term memory and working memory are two closely-related concepts that involve the prefrontal and parietal areas. These two types of memory have been evaluated by means of the spatial span task in its forward and backward conditions, respectively. To determine possible neurofunctional differences between them, this study recorded electroencephalographic activity (EEG) in the frontopolar (Fp1, Fp2), dorsolateral (F3, F4), and parietal (P3 and P4) areas during performance of the forward and backward conditions of this task in young men. The backward condition (an indicator of working memory) was characterized by fewer correct answers, higher absolute power (AP) of the delta band in dorsolateral areas, and a lower correlation between frontopolar and dorsolateral regions in the fast bands (alpha, beta and gamma), mainly in the right hemisphere. The prefrontal EEG changes during backward performance may be associated with the higher attentional demands and inhibition processes required to invert the order of reproduction of a sequence. These data provide evidence that the forward and backward conditions of the spatial span task can be distinguished on the basis of neurofunctional activity and performance, and that each one is associated with a distinct pattern of electrical activity and synchronization between prefrontal areas. The higher AP of the delta band and lower correlation of the fast bands, particularly between right prefrontal areas during the backward condition of this visuospatial task, suggest greater participation by the right prefrontal areas in working memory.

Verbal and visuospatial working memory during pregnancy: EEG correlation between the prefrontal and parietal cortices.

Pregnancy is a dynamic process during which significant cognitive changes take place. It has been suggested that working memory (WM) is affected during gestation as a result of functional changes among cortical areas, such as the prefrontal and parietal cortices. This study examined cortical electroencephalographic correlations (rEEG) during performance of WM tasks in each trimester of pregnancy. Forty women were divided into 4 groups: first (T1), second (T2), and third (T3) trimester of pregnancy, and a control group of non-pregnant women. Electroencephalographic activity (EEG) was recorded from the frontopolar, dorsolateral and parietal cortices during performance of one verbal and one visuospatial working memory task. Only groups T2 and T3 showed increased onset latency in the visuospatial WM. During the verbal WM task, the T1 group showed a higher correlation between dorsolateral areas in the theta and alpha bands, as well as a lower left prefrontal-parietal correlation in the gamma band. During the visuospatial WM task, the T1 and T3 groups showed a higher left EEG correlation in the delta and alpha1 bands, whereas T2 presented a higher right prefrontal-parietal correlation in the gamma band. Although pregnancy had only a subtle effect on the visuospatial WM task, these different patterns of cortical synchronization in each trimester of pregnancy could represent adaptive mechanisms that enabled the pregnant women to focus their attention and use more cognitive resources and so adequately solve the WM tasks.

Effect of Sexual Arousal on Cortical Coupling During Performance of the Tower of Hanoi Task in Young Men.

Sexual arousal affects cognitive processing, which depends on the coordinated functioning among cortical areas. The aim of this research was to determine whether previous observation of videos with sexual content affects the degree of cortical electroencephalographic (EEG) coupling during performance of an executive task. Cortical EEG correlations were calculated in three groups of heterosexual men under three conditions: at rest; during observation of a video with neutral, aggressive, or erotic content; and while performing the Tower of Hanoi task (TOH). Based on self-reports, it was shown that the erotic video induced general and sexual arousal, while the aggressive video affected valence and general arousal. Task performance was similar in all three groups. During performance of TOH, only the erotic group showed a decreased correlation between prefrontal areas with an increased correlation between parietal and prefrontotemporal areas, specifically in the slow bands. It is likely that these changes in the degree of cortical coupling could be associated with the cognitive strategies or functional adaptations that participants require to adequately solve the task during a state of sexual arousal. These data could contribute to improving our understanding of the central nervous mechanisms that underlie the effect of sexual arousal on the cognitive processes involved in tasks like TOH.

Sexual arousal decreases the functional synchronization between cortical areas in young men.

The prefrontal cortex and its connections with other cortical areas participate in processing erotic stimuli and hence sexual arousal. Visual erotic stimuli elicit sexual arousal that is associated with changes in electroencephalographic activity. The electroencephalographic correlation analysis provides information on the functional synchronization among areas. This study analyzed the functional interaction among the prefrontal, parietal, and temporal cortices during sexual arousal in young men induced by observing erotic photographs. In 2 groups of heterosexual men-an erotic stimulation group and a neutral stimulation group-the authors recorded electroencephalograms at the F3, F4, T3, T4, P3, and P4 derivations under 2 conditions: baseline and visual stimulation. Heart rate was monitored as a measure of peripheral activation. Participants in the erotic stimulation group reported a moderate degree of sexual arousal and a decrease in heart rate. Decreased inter- and intrahemispheric correlations of the fast frequencies were obtained only in erotic stimulation. These data support differential hemisphere participation in modulating sexual arousal and show that decreased synchronization patterns between prefrontal and posterior cortices (parietal and temporal) favor sexual arousal in young men. The results of this study may contribute to a better understanding of the central nervous system's mechanisms that underlie sexual arousal.