Being lost in the wrinkles of middle age, it took a national newspaper telephoning us yesterday requesting a psychological analysis of why Rihanna has been posting suggestive images on Twitter, before we understood the celebrity story of the moment.

After apologising that we couldn't help, the feature editor's question - what do these photos and postings reveal about this celebrity's state of mind - reminded us psychologists have begun to pose this question generally about more ordinary internet users. Behavioural scientists wonder if new technology is shaping our personality, and whether sites such as Facebook, MySpace and Twitter are driving a new narcissism epidemic?

Some academics have produced research suggesting we are the most self-centred, self-obsessed generation in history, and the internet may partly be to blame.

A new study just published entitled Narcissism or Openness? College Students' Use of Facebook and Twitter, is one of a growing number of scientific attempts to answer the question of whether our tweets reveal we are all becoming diva's?

The authors of the investigation, Bruce McKinney, professor in the Department of Communication Studies at the University of North Carolina-Wilmington, Lynne Kelly, and Robert Duran, both professors in the Department of Communication at the University of Hartford, USA, were prompted to conduct the research because Twitter indeed seems a perfect tool for revealing otherwise hidden narcissism.

The belief that there is an audience interested in following one's moment-to-moment postings suggests to some psychologists, egocentrism, self-aggrandisement, and self-importance, all characteristic of the excessively narcissistic.

This new study, just published in the academic journal Communication Research Reports, surveyed 233 undergraduates and found those with significantly higher scores on narcissism also reported sending more tweets about themselves. Narcissism was unrelated to the frequency of using Facebook to post about oneself but, was related to a larger number of Facebook friends.

Since narcissists tend to alienate others over time, they may prefer the more superficial connections, not marked by emotional closeness, social networking sites can provide. Previous research confirms narcissism is related to the number of 'friends' on sites like Facebook, but not the number of true friends, in real life.

Narcissism in extreme form becomes a personality disorder characterised by a grandiose sense of self-importance, fantasies of unlimited power, conceit and superficial relationships.

Jean Twenge, a professor of psychology at San Diego State Univeristy, and Keith Campbell, professor of psychology at the University of Georgia, authored a new book entitled The Narcissism Epidemic: Living in the Age of Entitlement, arguing we are in the grip of a new narcissism pandemic escalating over the past two decades.

Studying more than 16,000 college students, Twenge and Campbell found that today's youth score substantially higher on narcissism than those of their age just 20 years ago. Two-thirds of recent college students scored above the average in narcissism, compared to half of the college students who took the same test in the late Seventies and early Eighties.

If narcissism is increasing, this is ominous for the mental health of future generations. It's associated with a strong sense of entitlement, which leads to unhappiness, through a sense of deprivation. Narcissists can't have proper deeper relationships because they merely seek to exploit others for their own ends - friends and lovers are always stepping stones to something better.

If it feels we live in angrier times then this may be linked to narcissism being associated with responding aggressively to insults, and slights, while it's also associated with vengeance seeking. Incidentally in the light of recent pop star photos, this might explain the use of Twitter as the battle ground for so many celebrity feuds.

Another recent investigation entitled 'The effect of social networking websites on positive self-views: An experimental investigation' found use of MySpace was linked to narcissism but not Facebook. The study published in the journal Computers in Human Behavior found spending just about half an hour editing one's MySpace page, and writing about it's meaning, was enough to significantly raise narcissism, suggesting that social networking sites may have profound impact on the development of personality and identity.

Yet those who spent time editing and thinking about their Facebook page reported higher levels of self-esteem, but not elevated levels of narcissism.

The authors of the research, Brittany Gentile, Jean Twenge, Elise Freeman and Keith Campbell argue the contrasting results, in terms of impact on narcissism between Facebook and MySpace, may be due to key differences between the sites.

MySpace, Brittany Gentile and colleagues contend, offers the opportunity for users to create a personal brand, customizing profiles using stylisation code, in contrast to the standard format used on Facebook. MySpace users also have the option to share more profile information publicly. Thus, MySpace may offer greater opportunities for self-expression and self-promotion than Facebook.

In addition, the authors argue, MySpace offers the potential for fame. Celebrities have been born out of the strength of their following (e.g., Tila Tequila, Jeffree Star) or unearthing their flair on MySpace (e.g., Colbie Caillat, Lily Allen). In contrast, Facebook markets itself by appealing to the more mundane project of keeping in touch with friends and family.

McKinney, Kelly, and Duran conclude from their study that it is not the technology that creates narcissism, as much as it is the narcissistic personality that seeks technologies allowing the user to become the centre of attention.

The authors also wonder whether social networking sites, in fostering a new culture of personal disclosure, might be positive psychologically in the longer run. Given the stigma and shame around mental health issues, for example, it remains to be seen whether the 'new openess' will improve our mental health, as there may be less shame and taboo in sharing what previous generations have regarded as private.

What these studies suggests is the way you use social media unerringly reveals your personality. So if you are aware of this latest psychological research, in fact you now possess greater tools and opportunities to get inside the mind of friends, colleagues, lovers, break-ups and adversaries, than ever before.