how to tell left and right on a brain scan after using imagesc

hello I have used imagesc to visualize a brain image that is in standard NIfTI format. How do I know which is right and left? I cannot tell from anatomical positions. The scaling on the x axis is from 0 to 256, and from 256 to 0 on the y axis (decreasing in the positive y direction).

[Tina]

https://docs.google.com/file/d/0BxTkZamMHH7_S2tQenZJZnhrWkk/edit

this is where the image is uploaded to

Answer 1

[Image Analyst]

Don't radiographs often have an R or L burned into the image somewhere? Where did you upload your image to?

[Tina]