The Effect of Intermittent Theta Burst Stimulation on Brain Characteristics, Pain Intensity, and Cognitive Functions in Older People with Chronic Musculoskeletal Pain.

Inclusion Criteria:

• have normal cognitive function (Hong Kong Montreal Cognitive Assessment ≥ 26)

• be right-handed

• be able to speak Cantonese

• chronic nonspecific low back pain, or having both chronic nonspecific low back painand chronic knee pain that has lasted for at least 3 months

• an average pain intensity of ≥ 5 out of 10 on an 11-point numerical rating scale inthe last 7 days, where 0 means "no pain" and 10 means "worst pain imaginable"

• having pain at least half of the days in the past 4 weeks.

• have at least 6 years of formal education and know how to read and write Chinese

• agree to sign an informed consent and complete the experiment tests

• be able to communicate via email or text message, as several study measures will becollected electronically

Exclusion Criteria:

• inability to ambulate without assistance from another person (canes or walkers willbe allowed);

• having specific causes of chronic nonspecific low back pain, or having both chronicnonspecific low back pain and chronic knee pain (e.g., spinal stenosis, lumbar discherniation, spondylolisthesis, recent vertebral fracture, spinal infection);

• having other concurrent musculoskeletal conditions at other body parts (e.g.,fibromyalgia, or neck pain)

• self-reported history of lumbar or lower extremity surgery

• self-reported history of neurological or psychiatric disorders (e.g., stroke, brainsurgery, head trauma; schizophrenia, multiple personality disorder, dissociativeidentity disorder, stroke) or self-reported cancer history

• self-reported specific inflammatory disorder: rheumatoid arthritis, rheumatica,scleroderma, lupus, or polymyositis

• unexplained, unintended weight loss of 20 lbs or more in the past year

• cauda equina syndrome

• uncorrected visual deficit

• drug or alcohol addiction

• taken alcohol, opioids or benzodiazepines medicines 24 hours before the experiment

• claustrophobia

• contraindications for undergoing the magnetic resonance imaging (MRI) examinationbased on the MRI safety screening form of University Research Facility in Behavioraland Systems Neuroscience (UBSN) at The Hong Kong Polytechnic University (PolyU)