Ten participants in group A will undergo robot-assisted hand (with visual feedback) combined with occupational therapy. They will receive 60 minutes a day and 3 days a week robot-assisted hand and occupational therapy for six weeks.

Another 10 participants allocated to the group B will receive 60 minutes a day and 3 days a week traditional occupational therapy for six weeks.

Robot-assisted hand group contains 15 minutes of grasp and release motion, 15 minutes of visual feedback training and 30 minutes traditions occupational therapy. Traditional occupational therapy includes cognition training, sensory-motor function therapy, passive ROM exercise, functional hand training, activity of daily living skill training, instruction of using assistive devices,and so on.

Box and Block Test is composed of a wooden box divided in two compartments by a partition and 150 blocks. The BBT administration consists of asking the client to move, one by one, the maximum number of blocks from one compartment of a box to another of equal size, within 60 seconds.

The box should be oriented lengthwise and placed at the client's midline, with the compartment holding the blocks oriented towards the hand being tested. In order to practice and register baseline scores, the test should begin with the unaffected upper limb.

Motor evoked potential (MEP) is recorded from abductor pollicis brevis muscles following direct transcranial magnetic stimulation (TMS) of motor cortex. All TMS is delivered with the participant seated upright on the chair. Both passive and active conditions, participants are instructed to relax their one hand in the seated position. TMS is delivered over the motor cortex (M1) using a concave double cone coil (Magstim Co., United Kingdom) attached to a BiStim magnetic stimulator (Magstim Co., United Kingdom). To locate the optimal site, stimuli are delivered over various points along the M1. The optimal site is the location on the M1 that evoked the greatest MEP amplitude in abductor pollicis brevis muscles. The onset latency and onset to peak amplitude will be assessed.

Purdue Pegboard Test is composed of a board with pins, collars and washers. The board contains two parallel rows with 25 holes in each row and the pins, collars and washers are located in cups at the top of the board. Four subtests constitute the Purdue Pegboard test. In the first three the subject has, within 30 seconds, to place the maximum number of pins: first with the dominated hand, then with the other hand and finally with both hands simultaneously (symmetric task). In the last subtest the subject uses alternate hands in order to make assemblies consisting of pins, collars and washers, in a 60-second period.

The score on the two first pins subtests is the number of pins inserted in the holes. The number of pairs of pins constitutes the score on the third subtest and finally the assembly score consists of the number of pins, collars and washers assembled. Another score is deduced by adding the scores obtained in the first three subtests (right hand + left hand + both hands).