Memorization of Sequences of Movements of the Right or the Left Hand by Right- and Left-Handers: Vector Coding.

In order to test the hypothesis of hemisphere specialization for different types of information coding (the right hemisphere, for positional coding; the left one, for vector coding), we analyzed the errors of right and left-handers during a task involving the memorization of sequences of movements by the left or the right hand, which activates vector coding by changing the order of movements in memorized sequences. The task was first performed by the right or the left hand, then by the opposite hand. It was found that both'right- and left-handers use the information about the previous movements of the dominant hand, but not of the non-dom" inant one.

[Memorization of Sequences of Movements of the Right and the Left Hand by Right- and Left-Handers].

We analyzed the errors of right- and left-handers when performing memorized sequences by the left or the right hand during the task which activates positional coding: after 6-10 times the order of movements changed (the positions remained the same during all task). The task was first performed by one ("initial") hand, and then by another one ("continuing"); there were 2 groups of right-handers and 2 groups of left-handers. It was found that the pattern of errors during the task performance by the initial hand is similar in right- and left-handers both for the dominant and non-dominant hand.

[Learning and Repetive Reproduction of Memorized Sequences by the Right and the Left Hand].

An important stage of learning a new skill is repetitive reproduction of one and the same sequence of movements, which plays a significant role in forming of the movement stereotypes. Two groups of right-handers repeatedly memorized (6-10 repetitions) the sequences of their hand transitions by experimenter in 6 positions, firstly by the right hand (RH), and then--by the left hand (LH) or vice versa. Random sequences previously unknown to the volunteers were reproduced in the 11 series.

[Non-invasive transcutaneous spinal cord stimulation facilitates locomotor activity in decerebrated and spinal cats].

It is known that spinal neuronal networks activated by epidural electrical stimulation (EES) can produce the stepping EMG pattern and control the locomotor behavior. At present study we showed that non-invasive transcutaneous electrical spinal cord stimulation (tESCS) applied to the lumbar-sacral enlargement can facilitate the locomotor activity in decerebrated and spinal animals. The comparison of the motor responses evoked by EES vs tESCS showed that both methods produce the locomotor patterns with close properties and similar reflex mechanisms.