Motivational Determinants of Sexting: Towards a Model Integrating the Research

Sexting, defined as the exchange of sexually explicit contents among adolescents and young adults using electronic media, has become a popular topic of interest in the wider public. This paper proposed a theoretical model to explain motivational determinants of sexting behaviour. We reviewed sexting literature to show how multiple empirical confirmed motivational factors can be modelled within our framework. By analysing empirical research, we posited a set of individual characteristics and contextual characteristics that explain sexting behaviour. We offered a systematic review of motivational determinants relevant to capture sexting behaviour and guidelines for future research in this area. We intended by this theory to organize prior research into a more theoretically satisfying approach to study sexting and to encourage researchers to expand the model and use it in future studies.


Introduction
The internet and smartphones are incorporated into all aspects of life and are the main social tools for adolescents and young adults (Campbell, 2005;Chalfen, 2009). Instead of going out and socializing outside the home, social interaction takes place through blogs, social networks and various applications intended for communication between users (Horst, Herr-Stephenson, & Robinson, 2010). Today, digital technology provides new ways of developing and maintaining social relationships and enables young people to define themselves as they use them (Simpson, 2013).
The virtual world is becoming part of everyday life, and it is difficult to separate it from real life (Ringrose, Gill, Livingstone, & Harvey, 2012;Van Doorn, 2011). All new phenomena have been in the focus of research interest over recent years with the development of modern technology (internet dependence, internet violence, sexting etc.).
Sexting, or the exchange of sexually explicit photographs by electronic media, is a relatively new form of communication. There is still no consensus amongst authors regarding the definition of this phenomenon, which is considered either as a potentially risky and deviant form of behaviour, or a completely normal form of communication, typical of the modern age of digital technology (see Döring, 2014;Rice et al., 2014).
The first part of this paper includes the definitions of the phenomenon of sexting, an examination of its various forms and the prevalence of this behaviour. We then describe theoretical approaches that try to explain sexting. A new theoretical model is also proposed, stemming from the results of research so far, aimed at examining the motivations of young people for participation in sexting.

Definition and Types of Sexting
In the scientific literature there are various definitions depending on the time of each definition, but also the authors working on the research (Drouin, Vogel, Surbey, & Stills, 2013;Klettke, Hallford, & Mellor, 2014). It is a recent phenomenon which was first defined by Chalfen (2009) as the exchange of provocative or sexually explicit content, such as text messages, photographs and/or video recordings, using smartphones, the internet and/or social networks. Alongside sending sexually explicit contents, more recent definitions also emphasize exchanging and forwarding such contents. For example, Hudson (2011) defines sexting as sending, posting, sharing or forwarding of sexually explicit messages and/or photographs through electronic media. Amongst the photographs revealing part of the sender's body, some also show intimate parts of their bodies in swimming costumes or underwear, some naked body parts or their entire body, and some even contain and show sexual activities (e.g. masturbation) (Mitchell, Finkelhor, Jones, & Wolak, 2012). Hudson (2011) added social networks and applications which enable electronic communication to the number of platforms and tools that permit the distribution of this kind of content.
Regarding types of sexting, Calvert (2009) differentiates primary and secondary sexting. Primary sexting occurs when a person sends their own personal photograph with sexual content to other persons. Secondary sexting relates to the forwarding of photographs with sexual content to other persons, where the person forwarding them is not depicted in the photographs being sent. Whilst primary sexting is consensual, that is, photographs with sexual content are sent with the consent of the person in the pictures, in the case of secondary sexting, it may happen that photographs are sent to other people without the knowledge or consent of the person depicted in the photographs (Calvert, 2009). Alongside these two basic forms of sexting, Calvert (2009Calvert ( , 2013 differentiates a third form, so-called "revenge sexting", which he defines as the public sharing of sexually explicit contents showing a former partner, without their consent. This form of sexting may also include information about the identity of the person shown in the photographs (Tungate, 2014). Behind another, a newer form of sexting, which authors (Dake, Price, Maziarz, & Ward, 2012;Tobin & Drouin, 2013) called unwanted but consensual sexting, we find pressure exerted by a partner or peer to send sexually explicit content.
The division of sexting into active and passive also stems from the research conducted so far. Active sexting includes creating, showing, publishing and sending sexually explicit contents to other persons, whilst passive sexting relates to receiving such contents (Temple & Choi, 2014). Further, the typology proposed by Wolak, Finkelhor, and Michell (2012) introduces factors for assessment of harm, emphasizing the difference between problematic and experimental sexting. Problematic sexting includes criminal elements and/or elements of abuse, and may relate to adults involved in exchanges of sexually explicit contents with minors, or to violent behaviour between peers, such as sexual abuse, extortion, threats and forwarding content against the will or without the knowledge of the person depicted in it. From this it follows that problematic sexting includes violence committed over the internet and/or using digital media for distribution of unpleasant, false or hostile information between peers. This form of sexting is considered to be risky behaviour which may result in negative outcomes (O'Keeffe & Clarke-Pearson, 2011). On the other hand, experimental sexting presumes the sending of one's own photographs or video recordings to friends and/or intimate partners, in the context of a romantic relationship or thrill-seeking. This form is not aimed at harming a person and does not include elements of criminal behaviour (Wolak & Finkelhor, 2011). The authors proposed the term experimental sexting precisely because there is no evidence that this behaviour goes beyond the framework of behaviour characteristic for the period of adolescence, including flirting, seeking potential partners, experimenting with sexuality, attracting the attention of peers etc. (Wolak & Mitchell, 2011).
On the basis of the above, it may be said that sexting is defined in different ways in the scientific literature, which also contributes to differences in its typology, as well as differences in the prevalence of this phenomenon. A review of research to date on the prevalence of sexting will be given in the next chapter.

The Prevalence of Sexting
A significant number of studies in this field have dealt with the prevalence of the exchange of sexually explicit content between young people in the period of adolescence and young adulthood. Comparisons of the existing results of the research are difficult due to the differences in the very definition of sexting, which authors of previous research have also emphasized (for example, Drouin et al., 2013;Lounsbury, Mitchell, & Finkelhor, 2011). Two groups of factors which also contribute to differences in the results obtained include the methodology of the research undertaken, related to the different samples of subjects, differences in the media used for sending sexually explicit contents, different content of messages sent (textual messages or photographs), and the status of the relationship within which sexually explicit messages are sent.
From a review of a total of 88 research, published in a five-year period, more precisely from January 2009 to September 2014, Cooper, Quayle, Jonsson, and Svedin (2016) report on the prevalence of sending and publishing sexually explicit messages amongst adolescents, as ranging from 7% to 27%. Analysing 18 research published in the period between 2012 and 2015, the authors Barrense-Dias, Berchtold, Surís, and Akre (2017) obtained a similar conclusion, according to which from 2.5% to 27.6% of adolescents were involved in active sexting. According to the results obtained from this research, passive sexting is more widespread, and 7.1% to 60% of adolescents engage in it.
Along with adolescents, the prevalence of sexting in young adult groups, aged from 18 to 25 years, was also examined. Studies showed that 20% to 48.5% of young adults had sent or published a naked or semi-naked photograph or video recording of themselves (Hudson, Fetro, & Ogletree, 2014;Reyns, Burek, Henson, & Fisher, 2013). Further, according to the results of the National Campaign to Prevent Teen and Unplanned Pregnancy and CosmoGirl.com from 2008, 59% of young adults had sent or published sexually explicit text messages, whilst 64% of them had received such messages.
From a review of recent research on the prevalence of sexting in the Republic of Croatia, it was found that 33.7% to 64.4% of young people had participated in sexting (Burić, Juretić, & Štulhofer, 2018;Kričkić, Šincek, & Babić Čikeš, 2017;Vrselja, Pacadi, & Marinčić, 2015). A study conducted on a sample of adolescents aged from 15 to 17 years by Vrselja et al. (2015) revealed that 39.9% of adolescents had sent or posted sexually explicit content in the media at least once in their lives. Longitudinal research  conducted on a sample of 791 young adolescents aged 16 years, showed that almost half the pupils had taken part in sending sexually explicit content. At the first point of measurement, between 36.6% and 46% of high school pupils had participated in sexting by sending sexually explicit messages at least once, whilst at the second point of measurement, the data were somewhat different and indicated a lower prevalence of sexting, between 33.7% and 37.7%. The prevalence of sexting in this country was also examined in a sample of students aged from 18 to 27 years (Kričkić et al., 2017). The results obtained show that 57.4% of students had taken part in sending and 64.4% in receiving sexually explicit contents. According to these results, 1% of students had forwarded or showed content received to persons for whom that content was not intended.
On the basis of the results obtained, both in national and foreign research, it follows that the prevalence of sexting in adolescence and young adulthood varies depending on the sample tested, but also on the actual operationalization of sexting. It is clear that there is a lack of systematic research on representative samples. Both in research and also in an educational and preventive sense, it is important to establish protective factors regarding sexting. For example, in the research by Tomić, Burić, and Štulhofer (2018) it was shown that parental supervision may play an important role in preventing negative outcomes from this phenomenon. Alongside parents, schools and teachers should work to develop successful relationships with pupils and offer a variety of extracurricular activities for children and young people (according to West et al. 2014). This knowledge, along with the knowledge of the risk factors, is vital and a prerequisite for the development of effective prevention programmes (Šincek, 2010).

The Determinants of Sexting
On the basis of a critical review of the research into sexting to date, it may be concluded that it is a rapidly growing area of research. Although research so far has covered various aspects and determinants of sexting, for an understanding of this phenomenon a theoretical approach is needed which will integrate the various findings of this research into a meaningful whole. By reviewing the literature, two theoretical models were found, stemming from the theory of social learning (Akers, 1998;Akers & Jensen, 2006;Brown, Clasen, & Eicher, 1986;Burgees & Akers, 1966;Rebellon, 2006;Southerland, 1947) and self-control (Gottfredson & Hirschi, 1990;Hirschi, 1979), which both indirectly explain participation in an exchange of sexually explicit contents. Both models start with the assumption that the determinants of delinquent behaviour are the same as the determinants of sexting. According to the theory of social learning, juveniles who socialize with peers who are more prone to delinquent behaviour, copy that behaviour because they are supported by their peers. At the same time, young people develop convictions about the positive consequences of delinquent behaviour, whereby that behaviour is established even more firmly. Delinquent behaviour gives young people some advantages, such as acceptance by their peer group, fun etc. A similar process applies to the tendency towards risky behaviour such as sexting. Further, one of the dominant explanations for delinquent behaviour is mentioned by Gottfredson and Hirschi (1990) as part of their theory of self-control. According to these authors, a low level of self-control predicts the development of delinquent behaviour. That is to say, the lack of self-control, as an individual determinant of delinquency, increases the tendency towards delinquency and seeking delinquent peer groups with whom individuals identify, and in that way, they reinforce their own delinquent behaviour.
On the basis of these components of the theory of social learning and selfcontrol, it is possible to draw conclusions indirectly regarding the causes of sexting. An important contribution of these theoretical approaches to explaining sexting, which is considered through these models as exclusively delinquent behaviour, is the identification of the importance of two types of factors (contextual and individual), of which the contextual factors stem from the theory of social learning, whilst individual factors stem from the theories of self-control. Although these models are useful in defining the determinants of sexting, since this phenomenon exists in different forms it is certainly necessary to place the emphasis on the empirical research undertaken in this field to date.
In this study, a model will be described which includes the theoretical elements of the two models described above, but also the results of previous research about why young people participate in the exchange of sexually explicit content. In the model presented, the risk factors for participating in sexting are categorized into several categories of individual and contextual factors, and they will be presented in that way in this paper ( Figure 1).  Regarding the individual determinants of motivation for participating in sexting, the results of research so far indicate three groups of determinants. One group relates to demographic characteristics, such as sex and age. The other group of individual determinants relates to cognitive characteristics, which are taken to be positive attitudes, expressions of social emancipation, realization of status in a group, and a response to peer group pressure. The characteristics and hallmarks of intimate relationships are the third group of individual characteristics, which are linked with the motivation for participation in sexting (Figure 1). Alongside the individual determinants, the contextual characteristics, which denote cultural and social values, are the second wider category of determinants of sexting. Contextual variables do not directly contribute to engaging in sexting but have an indirect effect through the complex relationship between the individual variables and sexting.
The results of research to date, from which the theoretical model defined in this way stems, will be presented below.

The Individual Determinants of Sexting
The first group of individual determinants of sexting includes demographic characteristics, which are supported by empirical results in this field. In relation to differences in sexting between girls and boys, the results of research undertaken so far have produced inconsistent results. Some research shows that young men and girls exchange sexually explicit contents by electronic media equally (Dake et al., 2012;Hinduja & Patchin, 2010;Rice et al., 2012), whilst others report that girls are more active than boys (Martinez-Prather & Vandiver, 2014;Mitchell et al., 2012;Reyns, Henson, & Fisher, 2014). Girls show a greater tendency towards sending sexual content in comparison with boys, whilst boys have a greater likelihood of receiving such messages (Gordon-Messer, Bauermeister, Grodzinski, & Zimmerman, 2013;Henderson & Morgan, 2011;Strassberg, McKinnon, Sustaita, & Rullo, 2013). In contrast to the results of the research mentioned previously, Jonsson, Priebe, Bladh, and Svedin (2014) found that young men more often participate in activities such as posting sexually explicit contents.
Although sexting, as a phenomenon of the modern age, may be considered as a form of promoting sexuality, the fact is that the social environment reacts differently in situations when girls and young men express their sexuality. Shaming, social isolation and other forms of punishment are more frequent reactions from the environment to expressions of sexuality by girls (Angelides, 2013;Ringrose, Harvey, Gill, & Livingstone, 2013). This comes to be expressed in sexting situations. In contrast to girls, for young men producing and sharing sexually explicit contents ensures a higher status amongst their peers. Young men are usually encouraged to collect sexually explicit contents from their female peers, as well as posting their own photographs on some social media. These activities actually confirm their masculinity, and they acquire approval and admiration from their peers (Ringrose et al., 2012). The people around tend to see and describe girls who participate in these or similar activities as insecure, with a lack of self-respect and/or people prone to promiscuous behaviour (Döring, 2012;Lippman & Campbell, 2014;Ringrose et al., 2012;Walker et al., 2013). People also show a tendency towards seeing girls as those who through reckless and irresponsible behaviour are seeking the attention of young men in the wrong way (Hasinoff, 2013;Karian, 2012;Ringrose et al., 2012Ringrose et al., , 2013. The double moral standards towards young men and girls are especially visible in situations where photographs are distributed to the public, when the responsibility for making and exchanging them is ascribed to the girls and not to those who are actually responsible for forwarding them without authorization (Hasinoff, 2013;Ringrose et al., 2013). It follows from this that sexting is far from a gender-neutral phenomenon and may be better understood if it is considered from the perspective of gender standards (Simpson, 2013). It also follows that sexting may be considered as a new form of abuse of women using the internet and social networks (Ringrose et al., 2012).
From research to date into the prevalence of sexting in different age groups of adolescents and young adults, certain inconsistencies may be seen. More specifically, research indicates that the prevalence of sexting increases with age. Adolescents aged 16 and 17 engage in exchanging sexually explicit contents more often than adolescents aged from 12 to 15 years (Dake et al., 2012;Mitchell et al., 2012;Rice et al., 2012;Strassberg et al., 2013). The trend of the rise in sexting during adolescence may be the result of increased sexual interest in that period of development (DeLamater & Friedrich, 2002). Adolescents in the period of middle and late adolescence, that is, the ages of 14 to 17 years, are more interested in sex than younger adolescents, aged 9 to 13 years. Moreover, older adolescents use mobile phones and the internet more, and are also less under the supervision of their parents in comparison with younger adolescents (Lenhart, Madden, & Hitlin, 2005;Livingstone, Haddon, Görzig, & Olafsson, 2011), which in the end results in more opportunities to engage in sexting. The trend of a rise in the prevalence of sexting in relation to age is also visible from research comparing the results from adolescents with the results of young adults (Lenhart & Duggan, 2014). In the research by Benotsh, Snipes, Martin, and Bull (2013) it was established that as many as 44% of the young adult participants engaged in sexting, but for all age groups receiving was more frequent than sending sexually explicit messages and photographs (Klettke et al., 2014). At a younger age, participation in sexting may be deemed to be normal, usual behaviour (Ott & Pfeiffer, 2009) whose purpose is to develop and explore one's own sexuality (Temple & Choi, 2014). Marganski (2017) explains this trend by the fact that younger adults use new technologies more often. Also, the large majority of them use social networks and the internet (Greenwood, Perrin, & Duggan, 2016).
Alongside the sex and age of individuals, for a complete understanding of sexting, it is certainly necessary to consider characteristics relating to the aspect of the cognitive processes that affect the decision by an individual to participate in sexting. This is a matter of attitudes, an expression of social emancipation, and a way to achieve popularity and status in a peer group.
Comparing the attitudes of people with experience of sexting and people who have not participated in this form of behaviour, the results of research to date (Jewel & Brown, 2012;Strassberg et al., 2013) report the more positive attitudes of people who have participated in sexting. Ferguson (2011) study on a sample of Hispanic women also showed the correlation between sexting and positive attitudes. In the research by Hudson (2011), it was found that attitudes towards sexting are in a positive correlation with subjective norms, which determine the intention, approval and actual behaviour related to sexting. According to the results of this research, positive attitudes were the strongest predictor of the intent for future participation in sexting by persons who had not yet had any experience of this form of behaviour. The expectation that sexting is an integral part of sexual behaviour in romantic relationships, and the attitude that sexting is fun, were also in a positive correlation with the exchange of sexually explicit text content and photographs in this research (Hudson, 2011).
An additional cognitive factor which also explains the motivation for participation in sexting relates to social emancipation. Adolescence is a specific period, characterised by social emancipation, the need for autonomy and freedom, and the development of skills which young people practice later in life (Ling, 2004(Ling, , 2005. The main part of the process of emancipation itself is, in fact, the widening of social relationships beyond one's own family, with the development of a feeling of one's own identity through interaction with other people (Ling, 2004). In other words, in the period of adolescence, the influence of the family and significant others becomes increasingly moderated by the influence of peers. Mobile communications actually have an integral role in the process of emancipation itself, enabling adolescents to create and maintain contact with their peers in a simple, quick and flexible manner. In this way, it is possible to explain why precisely adolescents are pioneers in the complete acceptance of mobile communications, as a means of social interaction. In fact, Ling (2004) believes that mobile phones have become the most important resource through which adolescents develop new autonomy and positioning with their peers. For an adolescent, owning a mobile phone means they have control over their own personal channel of communication, which enables them to have an independent relationship with others. As well as its central role in social interactions, mobile communication has also become the primary resource of young people in testing their own boundaries. Research shows a positive relationship between use of mobile phones and risky behaviours such as consumption of alcohol, problems at school and sexual activity (Ling, 2005). Taking this into account, from the developmental perspective, sexting may be deemed to be one form of exploration of sexuality and the development of individual independence. Peer pressure relates to the behaviour of peers, who, using various methods such as pressure, mockery, peer violence or explicit messages, endeavour to affect the attitudes and/or behaviour of individuals (Brown, Bakken, Ameringer, & Mahon, 2008). According to a large number of authors, no form of potentially risky behaviour in young people exerts so much pressure from peers as sexting (Collins & Steinberg, 2006;Lippman & Campbell, 2014;Vanden Abeele, Campbell, Eggermont, & Roe, 2014). In the period of adolescence, engaging in potentially risky behaviours stems from the desire for acceptance within a peer group (Brown, Clasen, & Eicher, 1986). In order to ensure better status and thereby satisfy their need for popularity, adolescents adjust their behaviour to the norms of the group they belong to (Asher & McDonald, 2009). Results so far show that popular boys and girls are more sexually active than their less popular peers (Mayeux, Sandstrom, & Cillessen, 2008;Prinstein, Choukas-Bradley, Helms, Brechwald, & Rancourt, 2011). If sexting is seen as a sexual activity, made possible by electronic media, and which contributes to achieving status, then it stems from this that this behaviour is at least partially motivated by the desire to achieve and maintain popularity in the peer group. In this context, the peer group may exert pressure on adolescents to participate in sexting and similar activities. The findings of recent research support this assumption. Research shows that girls, by participating in sexting, acquire attention, popularity, and acceptance from boys (Lippman & Campbell, 2014;Ringrose et al., 2012;Vandeen Abeele, Roe, & Eggermont, 2012;Walker et al., 2013). On the other hand, through sexting boys acquire communication skills, which include persuading girls to show them their bodies. Receiving and forwarding photographs of parts of girls' bodies, especially their breasts, according to research to date, are motivated by boys demonstrating their own sexual activity and acquiring status amongst their peers (Ringrose et al., 2012(Ringrose et al., , 2013. Adolescents also state that they and their peers participate in sexting in order to show that they are desirable and attractive, and to compete in terms of attractiveness (Chalfen, 2009;Ringrose et al., 2012). These motives indicate that sexting is a way of presenting one's own physical attractiveness and accomplishments, which are actually important indicators of visibility and social domination in a peer group (Closson, 2009;Lafontana & Cillessen, 2002). Forwarding sexually explicit photographs of peers without their approval (Bond, 2010;Ringrose et al., 2012) stems from the desire for social domination (Ahn, Garandeau, & Rodkin, 2010;Closson, 2009).
Further, in the context of individual determinants, it should be mentioned that the characteristics of intimate relationships are relevant for an understanding of sexting, especially in view of the fact that sexting may be deemed to be a form of intimacy. In the context of intimate relationships, pressure most often takes place in situations where one of the partners asks the other partner, with whom he or she is in an intimate relationship, to send sexually explicit photographs of themselves, or to participate in a mutual exchange of photographs of that type (Döring, 2012;Lippman & Campbell, 2014). Lippman and Campbell (2014) analysed data obtained from focus groups using a sample of American adolescents aged 12 to 18 years. Their results show that girls are afraid that boys will no longer talk to them if they do not respond positively to their request to send a (semi)naked photograph, or that they will find them uninteresting if they refuse to participate in such activities. The findings of other research consistently report that girls agree to activities such as "undesirable" independent photographs, and sharing photographs which for them represent a form of "sexual alignment" or the "undesirable price" which they have to pay, in order to maintain a romantic relationship with their partner (Lippman & Campbell, 2014;Renfrow & Rollo, 2014). Moreover, research confirms that girls participate in sexting because it is expected of them and deemed to be normal behaviour in an intimate relationship (Walker et al., 2013). Recently, there is an increasing number of indicators that adolescents, as part of their romantic relationships, mutually agree to exchange sexually explicit contents, especially during times when they are physically separated from their partner (Albury & Crawford, 2012;Döring, 2012;Walker et al., 2013). This form of behaviour for adolescents is a normal way of expressing personal sexuality, intimacy and communication within an intimate relationship (Döring, 2014;Hasinoff, 2013;Karian, 2012;Renfrow & Rollo, 2014). Sending or exchanging sexually explicit photographs to a partner with whom they are in an intimate relationship demonstrates that they are in love and/or shows their confidence (Albury & Crawford, 2012;Delevi & Weisskirch, 2013;Döring, 2012;Ringrose et al., 2012;Weisskirch & Delevi, 2011). Young people also send their partner text messages or sexually explicit photographs as foreplay, that is, as an introduction or initiation of real-life sexual behaviour, or to demonstrate their readiness for an intimate relationship (Lippman & Campbell, 2014;Temple & Choi, 2014). Young people very often use sexually explicit photographs in order to arouse attention, romantic or sexual interest in a person they like, but with whom they are not currently in a romantic relationship (Henderson & Morgan, 2011;Lenhart, 2009;Lippman & Campbell, 2014). Further, some young people use sexting to make them feel attractive and aroused (Dir, Coskunpinar, Steiner, & Cyders, 2013;Henderson & Morgan, 2011;Perkins, Becker, Tehee, & Mackelprang, 2014;Renfrow & Rollo, 2014;Weisskirch & Delevi, 2011) and seductive (Lenhart, 2009). In the end, for some young people, sexting is a "safe" sexual activity, insofar as they do not want to engage in sexual relations for health and/or religious reasons. Although additional research is needed in this field, some authors believe that sexting is a way young people experiment because it allows them to express their sexuality without any risk of pregnancy or sexually transmitted diseases (Chalfen, 2009;Lippman & Campbell, 2014).
In conclusoin, from the results of the research to date it follows that it is not necessary to perceive sexting only as a form of risky behaviour. Exchanging sexually explicit contents may also be a way of expressing intimacy and/or fun.

The Contextual Determinants of Sexting
Over the past decade, sexuality has become extremely visual, commercialised and thematized in popular culture, through social networks, films and video recordings (Ringrose et al., 2012). Elements of a culture in which intimate relationships are discussed in a very open manner, where there is easy access to pornography on the internet, and advertising with sexual content is very present in the media, have contributed to a social context where sexuality is no longer a taboo subject (Ringrose et al., 2012). From this, it follows that sexting may be considered in the context of a markedly sexual consumer culture, which is dominant in contemporary society (Lippman & Campbell, 2014;Ringrose et al., 2012;Walker et al., 2013).
In the context of these changes in society and in the perception of sexuality, activities such as the exchange of sexually explicit contents via the electronic media have become an integral part of the sexual behaviour of young people. Chalfen (2009) states that sexting is in fact what happened before, the exchange of words and photographs, but in a way that is in line with the current media, and the technological changes and possibilities which have brought about those changes. Some other authors believe that sexting is only a new form of experimentation with sexuality in the period of adolescence and that young people have always used technology in some form to express their sexuality (Chalfen, 2009;Hand, Chung, & Peters, 2009). The values that dominate in society form the attitudes and behaviour of members of that society (Schwartz & Boehnke, 2004). For example, they determine the extent to which women are subject to limitations by society in expressing their sexuality (DeLamater, 1981). In sexually restrictive societies, traditional values are dominant, through which the traditional gender roles are emphasized and the sexual passivity of women and the domination of men are promoted (Kiefer & Sanchez, 2007;Marston & King, 2006). In contrast, in sexually permissive societies gender differences in sexuality are in general less clear (Petersen & Hyde, 2010), and it is usual for women to express their sexual desires and needs (Weinberg, Lottes, & Shaver, 1995). Research shows a lower tendency towards potentially risky sexual behaviours in traditional societies (Kloep, Gueney, Cok, & Simsek, 2009) which may be a result of restrictive child-rearing methods (Alwin & Felson, 2010). Traditional societies also have a strong influence on the sexual behaviour of adolescents and may restrict them in their expression of sexuality (Sharabany, Eshel, & Hakim, 2008). In traditional, sexually restrictive societies, the sexuality of adolescents may be perceived as unacceptable. In such societies, the exchange of sexually explicit photographs may be perceived as unacceptable behaviour for girls. However, young men may be expected to participate in exchanges of sexually explicit contents. In sexually permissive societies, the sexuality of adolescents is perceived as a normal phase of development (Weinberg et al., 1995), and it is acceptable for adolescent girls to express their sexuality too. The openness of society towards this form of sexual activity results in the fact that adolescent girls are more willing to send photographs and textual messages with sexual content. A comparison of European countries in terms of social values shows that, despite the homogeneity of some of their social characteristics, there are still some noticeable differences in social values (Widmer, Treas, & Newcomb, 1998). More liberal sexual attitudes are to be found more often in countries in north-western Europe, such as Sweden, Denmark and Norway (Arnett & Balle-Jensen, 1993;Weinberg et al., 1995), in comparison with countries in southern Europe, such as Italy, and some eastern European countries such as Poland (Widmer et al., 1998). In this context, it is to be expected that cultural values will affect the prevalence of sexting, that is, in more sexually permissive societies gender differences in sexting are less expressed than in traditional societies. Although society may influence the prevalence of this phenomenon, most research to date has been undertaken on American samples. There is a lack of research from different European countries, as well as the comparison of the prevalence of sexting, which would contribute to a better understanding of the culture-specific variations of this phenomenon.

Conclusion
The fact that there are very few review articles on the motivational determinants of sexting prompted us to undertake a more comprehensive consideration of the motivational factors for participation in sexting. In view of the fact that the results of empirical research to date have tested a wide range of determinants, we endeavoured to group them into one general model of sexting that covers two wider categories. The individual characteristics which act on the motivation to participate in sexting are sex, age and cognitive characteristics, and the characteristics stemming from intimate relationships. The contextual determinants of participation in sexting include the perception of cultural and social values. In a critical review of the results of research to date relating to the individual determinants of sexting, it follows that there are still clear differences whereby young men engage in sexting more often than girls. Shaming, social isolation and other forms of punishment are frequent reactions to expressions of sexuality by girls. Sexting, according to the results of research undertaken, is most frequent in the period of young adulthood, although the first experimenting already begins in early adolescence. A more positive attitude in young people towards this form of behaviour also contributes to participating in sexting. Further, the needs for exploring sexuality, realizing social emancipation and improving one's social status and social domination in one's peer group increase the tendency towards participation in exchanges of sexually explicit contents. A young person's decision to participate may also be made under pressure from a partner in order to maintain an intimate relationship, attract attention and/or prompt the romantic or sexual interest of a potential partner. Although some authors deem sexting to be risky behaviour, the results of research so far indicate that sexting may also be seen as an integral part of a romantic relationship. The influence of social values and culture is also not negligible. The social context within which sexuality is no longer taboo is dominant today in contemporary societies and contributes to the willingness of an individual to participate in sexting.
In this review, the main motivational determinants for participation in sexting are presented. Since this is a relatively new phenomenon more research still needs to be done. It is probably a complex and dynamic process in which various individual and contextual characteristics interact with one another. Alongside the various determinants of sexting, the aspects of the contextual determinants which have moderating and mediating functions in the relationship between sexting and individual characteristics, and vice versa, should be studied. The results regarding the relationship between the individual and the contextual determinants should be tested on samples of participants with different socio-demographic characteristics. It is necessary to use precise operationalization of the constructs of sexting in the research. In this field, more recent methods of collecting data, such as social network analysis, are also welcome. Although this is a relatively new approach, social network analysis may be appropriate in researching the interaction between various individuals in on-line communication, such as sexting. This is an analytical technique, aimed at providing insight into the structure and characteristics of individual networks. Each network has nodes (entities) and ties between the various nodes (entities) (see Kopal, Korkut, & Krnjašić, 2016). For example, in the context of sexting, study groups could be analysed that may represent a network of research interest. In this case, the nodes in the network could be students, with different individual characteristics, and different types of sexting could be the ties between students, that is, the nodes.
In summary, future research aimed at shedding light on the mutual relationships and identification of new individual and/or contextual characteristics are needed and could contribute to a better understanding of the motivations and decisions to participate in sexting.