In the following google spreadsheet link, I analyzed 64 friends' profile photo in a chatting software called Wechat (which has the same function as messenger but preferred by Chinese) and trying to connect those images with who they are or who they want to be. And then I will present you my findings. (Here is a complete explanation for Wechat : https://en.wikipedia.org/wiki/WeChat)
Now, ladies and gentlemen, I present you my humble spreadsheet :D (In the file, please double click the blank to show the whole sentence)
I'll start my summary by first talking about my profile photo. I have never used a photo with myself in it because I don't like showing off my face in public place like Wechat. Instead, I prefer using scenes like sunset or a cloudy sky. In a way, I'm talking to someone viewing my profile image that I love nature scenes. In another way, I'm saying how I'm doing these days and how I'm looking at certain things like sky. More importantly, I'm hoping that someone would find out what I meant to say through the image so that I can share my thoughts with others. In the spreadsheet, only 25 out of 64 people chose to use imaginary images to present themselves in public. For these 25 people, we can't say that they have some problem with public media, but they are trying to communicate with the person looking at his or hers profile picture. They are trying to share their interest. Sometimes this kind of images can better show a person's interest than just a selfie. It is not necessarily the case that the imaginary photo is what the person want to become, but in my case and in several other cases, that is actually what we are trying to become.
As for the other 39 people who are using real life image as their profile photo, they have a lot more purpose to do that. The very first main purpose is to tell people what's they are like now (since I haven't encounter someone using his/hers photo as kids) and how they look like. The profile picture always give others the first impression of the user, most of the faces in profile images are smiling or showing the active side of the person, like Aiqi's profile photo with her friend. The message passed through these kind of profile images is "hi, I'm active, friendly and social. Plz come and chat with me and I will be nice with you :D" (I'm trying to write in online style). In another word, these photos show the life attitude for most of them (just in case someone are tricking others by presenting misleading pictures) and how they want other people to understand them.
What I'm trying to explain here is that the profile photos are not just something people use to fill the blank, but a very important tool for them to present themselves. No doubt there are a million ways to do that, so we have to ask why they chose that specific photo to show themselves to the public. The answer, from my perspective, is that people are trying to communicate through a single profile image, although there are some who doesn't care, they are trying to tell others their interest, their life, their attitude, their minds and how they look at the world. From the psychological perspective, people are always seeking for self-identity and self-identity is something which sometimes needs others' approve to achieve. And this is also the answer for why are people using anime or nature pictures to present themselves-- because they can find their self-identity in those scenarios instead of a picture that only shows little part of their life.
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