To qualify for Social Security Disability benefits, a claimant must have a “severe” impairment. An impairment or combination if impairments is “severe” within the meaning of the regulations if it significantly limits an individual’s ability to perform basic work activities. An impairment or combination of impairments is “not severe” when medical and other evidence establish only a slight abnormality that would have no more than a minimal effect on an individual’s ability to work.