Was Jake Gyllenhaal's character in Nightcrawler a sociopath or psychopath?

People can have different views or opinions on Jake Gyllenhaal's character in Nightcrawler as Lou Bloom. The term I could come up with, falls somewhere between a Realist and a Sociopath.

A Realist

Taken from his very own words he said in the movie, that he set his goals high and doesn't wait for the chances to happen rather he makes them with facts studying from the internet. And also he would not ask anything from his crew that he wouldn't do himself.

A Sociopath

He doesn't care about people's lives or feelings. Everything about him is self-absorbed. He doesn't care to take the lives of his partner Rick or his competitor. He also doesn't care for his friend Nina's feelings while negotiating the price of a video and again when he demands her to do uncomfortable things while they're alone in her apartment.

Also check this Reception section in Wiki page to know more about Critics opinions.

Reviewers call Gyllenhaal's character a "charming sociopath" and his performance "a bravura, career-changing tour-de-force."Christy Lemire of the Chicago Sun-Times called Gyllenhaal's performance "supremely creepy" and praised the film's themes and messages. Christopher Orr of The Atlantic compared Gyllenhaal to a young Robert De Niro and his performances in the films Taxi Driver and The King of Comedy, feeling Gyllenhaal's character harbored traits shared by De Niro's characters in the two films. Orr called Gyllenhaal "tremendous" in the role and stated that the actor is learning to "channel an eerie, inner charisma, offering it up in glimpses and glimmers rather than all at once." He also declared the role as Gyllenhaal's "best performance to date." Ben Sachs of the Chicago Reader said, "For a first-time director, Gilroy demonstrates an uncommon assurance, not only in his audacious tonal shifts but in the stellar work he elicits from his cast and crew."

I'm not sure there is a difference between the two terms. With no credentials to back my position, I believe Lou is a sociopath based on these characteristics:

1. Lou shows no empathy. This trait is demonstrated repeatedly.
2. Lou uses others to achieve his goals.
3. Lou is not a "Dexter" type sociopath where he needs to kill, but he demonstrates that hurting others is acceptable in order to "win", and he does not take responsibility for their harm.
4. Lou selfishly seeks credit and recognition by not sharing this credit with others.

While they share the same diagnosis, there is a difference between sociopath and psychopath though many do use them interchangeably. The main difference between a psychopath and a sociopath is that a psychopath stays calm and their vitals stay level no matter their actions. A sociopath feels emotions and their vitals vary accordingly.Think Hannibal vs Buffalo Bill. I would consider the character in Nightcrawler to be a psycho based on these differences. He is consistently calm in a way that makes it the first thing you notice. He's also overly-charming to the point of being creepy.

Resources: pretty much any psych website or journal you read, this is the age of google scholar and ebscohost; several years of study in abnormal psychology (for an as-of-yet unfinished minor, so take that for whatever you think it's worth)

The character arguably demonstrates psychopathological (i.e. abnormal) characteristics of a sociopathic (i.e. anti-social) varietal. As a clinical diagnosis, sociopathy also identifies a lack of conscience, yet Lou Bloom's character arguable acts upon his conscience (i.e. how he distinguishes right and wrong). However abnormal his conscience and personality may be is in a large part a measure of what each viewer brings to the film.

In answering such a question it is worth noting that the conclusions of psychology are opinion, not the confirmation of hypotheses. Inasmuch, Lou Bloom's certainly an odd bird. Given his career choice, the film-makers are commenting upon the character of news media, consumer culture and capitalism as much as the individual fictional character of Bloom.

I think the strongest explicit evidence in the film that Bloom is psychopathological is that he intentionally sabotages his professional competitor's vehicle in such a way as to cause a considerable accident. That he is manipulative and controlling - especially for his sexual gratification - is not by itself psychopathological. In the context of how inappropriate his behavior consistently is (entering victim's homes, his non-reaction to his employee's murder), however, the portrait is unsympathetic yet compelling in such a way as to raise many questions. Did he know his employee would get shot? I think the film-makers leave the answer up to the viewer.