The Effect Of Source Credibility On News Discrimination In Older Adults And Its Neural Basis

With the development of the Internet and social media,it is more and more convenient for people to publish and contact information,which promotes the transmission of information and the acquisition of knowledge.However,it also lowers the threshold of information release,leading to the frequent occurrence of untrue information.A study on the Twitter platform of fake news during the 2016 US election found that older people were more likely to be exposed to fake news sites(Grinberg et al.,2019).As a result,the study of older people's discrimination of fake news has attracted more and more researchers.The purpose of this study is to reveal the behavioral characteristics and neural basis of false news discrimination in the elderly population.In Experiment 1,the truth perceptual discrimination and sharing discrimination of the elderly and the young on news with different sources of credibility were compared to reveal the specific effect of information source credibility on the elderly's discrimination in fake news.Older and younger adults were presented with true and false news from different sources and asked to judge whether the news was true or not and whether they were willing to share current news.The results showed that for true news,both groups showed high recognition ability,and the recognition rate was more than 70%.Statistical test showed that the main effect of source credibility was significant.After the comparison,it was found that the recognition accuracy was the highest and the misclassification rate was the lowest under the condition of no source,which was significantly higher or lower than that under the condition of high credibility.In the correct identification rate,the age main effect margin is significant,the old people's correct identification rate is significantly higher than the young people.The results indicate that the audience is more likely to make the correct identification when the real news information is unlabeled,and the elderly have certain advantages in this accurate identification.For fake news,the accuracy of both groups was less than 50%,and statistical tests did not find any significant effect.The results suggest that neither source credibility markers nor age affect the audience's identification of fake news.Taking the truth discrimination as an indicator,the results of the participants' behavior of true news and false news were taken into consideration.It was found that the main effect of age was significant,and the truth discrimination of the elderly was significantly higher than that of the young,and the age effect was not affected by the trustworthiness of news sources.True news and fake news showed a consistent trend in sharing data.The statistical test only found that the main effect of age was significant,and the sharing rate of the elderly was significantly higher than that of college students,and this sharing behavior was not affected by the credibility of the source of real news.In terms of sharing discrimination,the main effect of age is also significant,and the elderly's sharing discrimination is significantly higher than that of college students.Combined with the above results of authenticity perception,this result suggests that the elderly are more willing to share news,which may have nothing to do with their judgment of authenticity of news content.The elderly are separated from the authenticity perception of news and sharing behavior.On the basis of Experiment 1,Experiment 2 further explored the neural basis of the separation of news authenticity discrimination ability and sharing discrimination ability of the elderly.In this study,structural magnetic resonance imaging was used to obtain the brain structure images of the subjects.Correlation analysis was conducted between the gray matter volume of each brain region and the ability to distinguish the truth of news and the ability to share news.The results showed that the volumes of the left middle frontal gyrus,left precentral gyrus and right dorsalateral superior frontal gyrus of the elderly were significantly smaller than those of the young.The gray matter volumes of these brain regions were negatively correlated with the news sharing rate,but not significantly correlated with the correct identification or misclassification of news.This result suggests that the perception of news authenticity and the decision to share may have different neural bases,which may be the reason why the elderly choose to forward news even though they clearly perceive the news to be untrue.