Associations Between Dependency on LINE Text Messaging and Occurrence of Negative Emotions in LINE Group Chats

Introduction

People spanning several generations are now using smartphones and other mobile devices on a daily basis for communication (Faulkner & Culwin, 2005; Skierkowski & Wood, 2012). Currently, the leading smartphone communication tool in Japan is the “Chat” text messaging function of the Line mobile app (hereinafter, the function and app are collectively referred to as “Line”), which is particularly widely used by young people. In 2016, 79.3% of teens and 96.3% of people in their 20s used Line (Ministry of Internal Affairs and Communications, 2017). Unlike previous generations, which mainly relied on handwritten letters and emails, which are tacitly understood as a form of asynchronous communication, text messaging via smartphones and other mobile devices requires users to exchange messages—that is, to reply—with haste (Kato & Kato, 2015; Kato, Kato, & Chida, 2013).

Line has a function that allows the sender to see whether their message has been read by the recipient (i.e., that the recipient has opened the sender’s message in Line); conversely, the sender can see that their message has not been read (i.e., that the recipient has not opened the sender’s message in Line) when the “Read” notification is not displayed (Hoyle, Das, Kapadia, Lee, & Vaniea, 2017). The presence of this function, also known as “read receipts,” on Line has given way to the naming of two phenomena: “unread/ignored,” which is when a sent message has not been read (or has been read via means other than opening Line) and has not been responded to, and “left on read,” which is when a sent message has been read, but has not been responded to. Line also has various other features, such as group chat—in which users can have simultaneous exchanges with multiple group members—and stickers, a new type of expressive image that can be sent and received. These features have diversified the forms of communication available to users, and are seen as benefits of using Line. However, they can also lead to various problems. One example is the negative emotions that occur when a user’s message has been read but not responded to (Kato, Kato, & Ozawa, 2017). In other words, users have come to feel greater pressure to respond immediately after reading a received message than with email and other forms of communication (Kato, 2016). Furthermore, group chat-rooms result in more instances of unread messages and read messages without responses compared to individual exchanges because the application displays only the number of views; thus, the sender cannot identify who has read their message and who has not (Usuki, Kato, Ozawa, & Kato, 2018). This problem is one factor behind reports that using group chats leads to interpersonal conflict and bullying (Schreiber, 2015).

Because Line is a communication tool, its use can invoke in users the various emotions associated with interpersonal relationships. In addition, there are gender differences; for example, high school girls use communication applications more often than high school boys in Japan (Ministry of Internal Affairs and Communications, 2014). According to research on gender differences in interpersonal dependency and internet use among high school students, girls, who use Twitter and Line more frequently than boys, tend to seek their own stability through close emotional relationships with others, while boys tend not to engage in communication toward those ends (Inagaki, Wada, & Horita, 2017). There are also gender differences in dependency on the Internet (Kimbrough, Guadagno, Muscanell, & Dill, 2013; Weiser, 2000, 2001). Girls show a noticeable dependency on aspects related to communication, while boys show a noticeable dependency on aspects related to games and online videos (Ministry of Internal Affairs and Communications, 2014). According to research on gender differences in internet dependency and how it correlates with academic life skills among high school students, anxiety over text messages has a substantial impact on academic life skills among girls; that is, girls tend to pay so much attention to text messages that they cannot spend time away from their mobile devices, which produces a psychological dependency on them (Inagaki, Wada, & Horita, 2016). As these examples demonstrate, in research on communication applications, it is necessary to analyze gender differences or focus investigations on the genders separately. In that spirit, this research focuses on female university students.