Currently, there is no known medical treatment that hastens the repair of damaged nerve and muscle. Using IGF-1 transgenic mice that specifically express human recombinant IGF-1 in skeletal muscle, we test the hypotheses that targeted gene expression of IGF-1 in skeletal muscle enhances motor nerve regeneration after a nerve crush injury. The IGF-1 transgene affects the initiation of the muscle repair process after nerve injury as shown by increased activation of SCA-1positive myogenic stem cells. Increased satellite cell differentiation and proliferation are observed in IGF-1 transgenic mice, shown by increased expression of Cyclin D1, MyoD, and myogenin. Expression of myogenin and nicotinic acetylcholine receptor subunits, initially increased in both wild-type and IGF-1 transgenic mice, are restored to normal levels at a faster rate in IGF-1 transgenic mice, which indicates a rescue of nerve-evoked muscle activity. Expression of the IGF-1 transgene in skeletal muscle results in accelerated recovery of saltatory nerve conduction, increased innervation as detected by neurofilament expression, and faster recovery of muscle mass. These studies demonstrate that local expression of IGF-1 augments the repair of injured nerve and muscle.

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The finger-tapping (FT) test has been used for almost a century to evaluate muscle control and motor ability in the upper extremities (1). This task is frequently used to quantitatively evaluate patients with Parkinson's disease (1), ataxia (2), Alzheimer's disease (3), and Korsakoff syndrome (4), as well as in individuals who have suffered an acute stroke (5). Moreover, the finger-tapping test is widely used to evaluate motor function in the upper limbs (6-8) and the relationship between hand preference and hand skill (9) in healthy individuals and to assess hand skill and coordination (10-12) for occupations in which the hands are essential. The finger-tapping test is also used for psychomotor evaluations (13)(14)(15)(16)(17)(18)(19)(20).The movement involved in single-finger tapping is complex and is affected by visual and auditory stimuli, emotional and physical health, and factors that impact the skeletal and nervous systems. The characterisation of finger-tapping by an average tapping interval or by a tapping rate can only provide a limited amount of information. However, constructing a mathematical function that has the best fit to a series of data points obtained for a complex movement possibly helps to understand the nature of the movement.Various techniques have been used to record the number of tappings in a certain test period and the average time passed between tappings (intertap-interval) in the fingertapping test, including a mechanical counter, an electronic switch, a telegraph key, and a computer keyboard associated with word processing software (7,8). However, the time resolution of these systems is either low or unpredictable. The ability of a system to determine only an average intertap-interval or a tapping speed for a complicated movement results in poor time resolution and carries no information on the time course of the movement. Previous studies on this topic have not considered the temporal changes that occur between consecutive tapping. Therefore, the present study evaluated the time course of average intertap-interval values and the patterns of variation in both the right and left hands of right-handed subjects using the TanTong Finger-Tap system (21,22 The finger-tapping test is a commonly employed quantitative assessment tool used to measure motor performance in the upper extremities. This task is a complex motion that is affected by external stimuli, mood and health status. The complexity of this task is difficult to explain with a single average intertap-interval value (time difference between successive tappings) which only provides general information and neglects the temporal effects of the aforementioned factors.

We used electrophysiological measures to investigate the effects of obstructive sleep apnea on attention, learning, and memory. Thirty subjects (OSA group, n = 15, control group n = 15) participated in n-back tests, accompanied by P300 recordings, to investigate working memory and attention. The mirror-drawing test was used to study procedural memory, and the trail-making test (TMT) was used to evaluate divided attention and executive function. No significant group difference in reaction time was found in the 0-back and 1-back tests. In the 2-back test, reaction times of patients were longer than those of the control group. No P300 wave was obtained in the OSA group in any (0-, 1-, or 2-back) n-back test. In contrast, in the control group, significant P300 waves were recorded except for the 2-back test. The mirror-drawing scores were unaffected by sleep apnea. There was no difference between groups in the TMT-A test on any of the trials. Although no group difference was found in the first or second trials of the TMT-B test, OSA patients were less successful in learning on the third trial. According to our study results, OSA affects attention and executive function adversely however, we could not detect a significant effect on working or procedural memory.

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