The investigator aims to find a correlation between brain structure and activity and spontaneous recovery of motor function following brain ischemic stroke by Analysis of MRI scans. The research includes stroke patients and healthy patients (control group).

The recovery process, especially the recovery of motor functions after an ischemic stroke, differs from one person to another. In recent years, there is more evidence of spontaneous biological recovery (SBR), which is independent of training or rehabilitation-induced recovery, throughout the post-stroke subacute phase. However, the neural basis associated with motor function in this recovery phase remains unknown. We believe that the research results may help to explain the neural mechanism which promotes or inhibits recovery.

Inclusion Criteria:

1. age between 21 years old and 80 years old
2. admission to the hospital 2-14 days after a first ischemic stroke, confirmed by CT, MRI or neurological report
3. residual unilateral upper extremity weakness
4. ability to give informed consent and understand the tasks involved.

Exclusion Criteria:

1. younger than 21 years old or older than 80 years old
2. cognitive impairment, as seen by a score of <20/30 on the Montreal Cognitive Assessment (MoCA)
3. history of a physical or neurological condition that interferes with study procedures or assessment of motor function (e.g. severe arthritis, severe neuropathy, Parkinson's disease)
4. contraindication to transcranial magnetic stimulation (TMS), such as deep brain stimulators or skull defect, presence of other metal devices or objects in the head, or a pacemaker
5. inability to sit in a chair and perform upper limb exercises for one hour at a time
6. inability to lie down in the MRI scanner for an hour
7. participation in another upper extremity rehabilitative therapy study during the study period
8. terminal illness
9. social and/or personal circumstances that interfere with the ability to return for therapy sessions and follow-up assessments
10. pregnancy
11. severe visuospatial neglect, as seen by a score of <44/54 on the Star Cancellation Test.

Thirty stroke patients (experimental group) will be recruited from Sheba Medical Center, and 30 healthy age and gender-matched participants (control group) with no history of neurological impairments will be recruited from the community for participation in the study.