Assessing to see if someone can pay attention to ACL 2 Low information will require positioning the person so you can see if they can hold their body posture upright against gravitational forces.
To Verify
While seated on the edge of the bed, does the person hold their head up and stand up if they can weight bear?
If they cannot weight bear, they should be able to hold their head up for at least 10 minutes. This confirms ACL 2 Low.