New media technologies make it necessary for scholars to reassess mass communication theories developed among legacy media. One such theory is the spiral of silence theory originally proposed by Noelle-Neumann in the 1970s. Increasing diversity of media content, selectivity, social networking site (SNS) interactivity, and the potential for anonymity have posed various challenges to its theoretical assumptions. While application of the spiral of silence in SNS contexts has been theorized, its empirical testing is scarce. To fill this void, the Pew 2012 Search, Social Networks, and Politics survey is used to test the theory. Results reveal that encountering agreeable political content predicts speaking out, while encountering disagreeable postings stifles opinion expression, supporting the spiral of silence theory in the SNS environment. However, certain uses of SNSs and psychological factors demonstrate a liberating effect on opinion expression.

This study examined 1371 TV news transcripts on Alzheimer's disease (AD) from 6 TV news networks during a 25-year period (1984-2008) employing the news framing perspective. Issues, sources, and episodic-thematic news about AD derived from the news framing perspective were analyzed. Results revealed that AD issues, such as treatments, personal stories, celebrities, and policy increased over time, whereas other issues including facts, causes, signs, and diagnosis received relatively limited news attention. Correlation analyses among episodic-thematic frames, issues, and sources found that episodic-thematic frames were positively linked with such issues as personal stories and policy and sources, including patients and politicians. The results suggest that although TV news covers episodic frames more than thematic ones, both frames can interact with each other to influence personal and social news about AD. Particularly, the role of celebrity affecting AD news at both individual and social levels is salient.

Although research has tested the spiral of silence theory using a variety of issues, little attention is paid to how the nature of the issues affects the spiral of silence processes. This study adopts issue typologies provided by Yeric and Todd and recommended by Salmon and Glynn to test the theory using three issues: immigration (transitory), gay marriage (emerging), and abortion (enduring). Using a nationwide survey of Facebook users (N = 1,046), this study investigates how the nature of issues influences the dynamics of the spiral of silence processes. Results identify issue-specific differences, especially regarding the opinion congruency. Theoretical implications for future tests of the spiral of silence theory and public opinion research are discussed.

News outlets use social media, especially Facebook, for content distribution and engagement. This exposes consumers to user comments before reading a news article, creating an environment where audiences judge content prior to reading the story. In response to Perloff's (2015) call for research exploring how social media cultivate hostile media effects, this work examines the effects of viewing comments prior to reading a news story on perceptions of bias and credibility. This application tests across issue topics and is not limited to strong partisans or individuals with high issue involvement to test effects on a broader population. Results show comments under Facebook news teasers influence perceptions of bias and credibility. Specifically, those exposed to congruent opinions reported lower perceptions of bias and higher perceptions credibility than exposed to incongruent opinions. Results extend the hostile media bias theory by focusing on all audiences and prescribes practical implications for news practitioners. K E Y W O R D S credibility, Facebook, hostile media bias, online comments The hostile media phenomenon contends that individuals, especially

Social network sites (SNSs) such as Facebook, Twitter, YouTube, and LinkedIn have recently attracted the attention of public opinion scholars. However, research testing existing public opinion theories in a social media context is scarce. This study represents arguably the first empirical examination of the spiral of silence theory in the social media environment. Through an experimental manipulation embedded in an Internet survey, respondents (N ¼ 760) were presented with a hypothetical scenario (i.e., friendly or hostile) concerning gay bullying, an issue suited for investigation due to its moral components. Willingness to self-censor and to some extent, congruency with the national opinion climate were significant predictors of various online opinion response strategies, indicating the presence of the spiral of silence phenomenon in the social media environment. However, individual characteristics such as issue importance were related to willingness to communicate about the issue, suggesting a liberating effect on opinion expression.Keywords social network sites, social media, spiral of silence, willingness to self-censor, issue importance, perceived opinion climate, online opinion expressionIn 2012, it was reported that 65% of all Internet users, and 87% of users under age 30, use social network sites (SNSs) such as Facebook (Zickuhr & Smith, 2012). SNSs allow individual users the ability to broadcast information publicly, essentially providing a new outlet for public expressions of opinion. As such, the growing popularity of SNSs has dramatically changed the way people communicate and discuss social and political issues.Recently, a great deal of media and public attention has focused on the topic of antigay bullying. Spurred by the number of suicides in late 2010 among youth in the gay, lesbian, bisexual, and transgender community (GLBT), this issue has increasingly become a topic of public debate. This