I want to use this kind of effect for a video I'm making as Depth of Field. I'm not sure exactly what it's called, though. It's not typical blurring, but there's a shimmer effect on the lights. It's hard to describe.
Its called Bokeh (Wikipedia) from the Japanese word for Blur. Its the light refraction of out of focus areas on a lens. The shape of it will differ depending on the number of blades on the aperture. The more blades the more circular it will appear which people often think of as smoother bokeh. Fewer apertures and you'll get something like a hexagonal bokeh.
A lot more about the subject can be found on the Photo.SE Tag Bokeh.
In Photoshop this can be faked to a degree using Filter → Blur → Lens Blur
The iPhone 7's "Portrait Mode" is also an attempt to fake depth of field as well as bokeh.