Cerebral Activity To Opposite-Sex Voices Reflected By Event-Related Potentials

Gender identification signals contain faces, sounds, smells, etc. From an evolutionary standpoint, gender identification signals play a very important role to find the right mate. This research pseudo-randomly presented male voices and female voices to participants and collected their EEG signals at the same time, then analyzed whether there are significant differences between ERP to same-sex voices and that to opposite-sex voices by event-related potential (ERP) technology, further infer if there exist special cognitive brain activities to opposite-sex voices, in other words, is there opposite-sex effect when processing voices? In explicit task (Experiment1), participants needed to judge the gender of each voice. It turns out that compared to same-sex voices, opposite-sex voices can elicit significant late positivity (LP) wave around750ms, and differences mainly concentrate over parietal-occipital recording electrodes. Results suggest there does exist specific cognitive processing of opposite-sex voices, whose late latency suggesting this specific processing may be associated with activities of mood or reward system. Implicit experiment task (Experiment2) demanded participants to react after hearing pure tone, but ignore the gender of voices. Results show that differences disappear between ERP to opposite-sex voices and that to same-sex voices, declaring that if the experiment task does not require participants to focus on the gender of voices, the specific cognitive process of opposite-sex voices will disappear. Results suggest the specific cognitive process of opposite-sex voices may need the participation of attention. Oddball task (Experiment3) only requested participants to concentrate on watching silent films, and leave out voices. Results indicate that there are still no differences between ERP to opposite-sex voices and that to same-sex voices. These results further illustrate the specific cognitive process of opposite-sex voices may be not an automatic processing, but may need higher cognitive processing to get involved, such as attention, mood, reward, etc. Results of this study provide experimental evidence for revealing the neural mechanism of opposite-sex voices processing.