Editorial Motor Control, 2014, 18, 327-330 http://dx.doi.org/10.1123/mc.2013-0093 © 2014 Human Kinetics, Inc.

The Bernstein Prize Nikolai A. Bernstein (1896–1966) was an outstanding scholar in the science of motor control. His work on the organization of movement was based on the idea that neither central nor peripheral influences alone could generate normal movement. He introduced the notion of the central nervous system as an integrator of information and described movement as a complex organization of dynamical interactions. His work laid the foundation for seminal studies by the Russian School of Motor Control, which strongly influenced motor control thought from the early 1930s up until the late 1980s when glasnost opened the doors for a widespread exodus of Russian scientists to the west. The International Society of Motor Control is a society of scientists worldwide who are dedicated to the advancement of knowledge and promotion of basic and applied research in the area of the neural control of movements in biological systems. The highest award of the ISMC is the Bernstein Prize, which is presented at each biennial meeting to an individual who “has made an exceptional contribution to the development of the area of motor control in the spirit of Nikolai Alexandrovich Bernstein.” The previous awardees are: •2005 Anatol G. Feldman •2007 Mark Latash •2009 Michael Turvey •2011 Scott Kelso This year’s Bernstein Prize was presented at the Progress in Motor Control IX meeting held in Montreal, Quebec in July 2013. The 2013 awardee is Grigori Orlovsky. The award was introduced by Anatol Feldman who collaborated with Orlovsky between 1971 and 1981 when they were at the Moscow Institute for Information Transmission Problems and Moscow State University, respectively. We are pleased to reproduce below, the text of Feldman’s introduction written together with Yuri Arshavsky, another close colleague and friend of Orlovsky and Feldman, as well as that of Orlovsky’s address at that meeting.


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Presentation of the Bernstein Prize to Grigori Orlovsky by Anatol Feldman Grigori (Grisha) Orlovsky, currently Professor Emeritus at the Nobel Institute for Neurophysiology (Stockholm, Sweden), is a brilliant, internationally renowned neuroscientist who has made substantial contributions to contemporary thinking in the area of motor control through the analysis of the neural control of movement in a wide spectrum of animal species—from mollusks to higher vertebrates. He played a pivotal role in the Moscow group of researchers that is known in the West as the Russian School of Motor Control. A brilliant experimentalist, he elaborated methods for studying neural activity in animals during motor behaviors produced in natural or near-natural environments. In particular, inspired by the ideas of Nikolai Bernstein on the hierarchical organization of motor control, Grisha Orlovsky together with Mark Shik and Feodor Severin discovered a center in the brain stem responsible for the control of locomotion in decerebrated cats. This method is now broadly used in neurophysiological laboratories around the world. His studies have greatly advanced our understanding of the control of locomotion and postural control at different neural levels – the spinal cord, brainstem, motor cortex, cerebellum and vestibular system. Many studies from his team have contributed to the classical repertoire and are incorporated into many neuroscience textbooks. Grisha Orlovsky is the author of about 200 papers and two books regularly consulted by students and researchers in neuroscience. Despite his age (80 years old), he continues to be active in research as evidenced by the fact that he published three experimental and one review paper on the neuronal mechanisms of postural control in mammals in 2012 alone. Grisha Orlovsky is a teacher who inspired many neuroscientists and students in the field. The Bernstein Prize from the ISMC is a timely recognition of his amazing achievements.

Acceptance Speech for the Bernstein Prize by Grigori Orlovsky Dear colleagues, I am very thankful to the International Society of Motor Control for this prize, named after Nikolai Bernstein, an outstanding Russian scientist. According to Bernstein, a reduction of the number of degrees of freedom is a necessary condition for successful control in complex biological systems. This issue is especially important for locomotion since this motor behavior is based on the coordinated activity of almost all body muscles; numerous motor centers in the brain cooperate while controlling locomotion; and all sensory systems are involved in supplying the motor centers with necessary information.

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During the last decades, the locomotor control system in different species, both vertebrate and invertebrate, has been studied in a number of laboratories, and I participated in some of these studies. A great variety of types of locomotion (walking, swimming, flying, crawling, etc.) has been analyzed. These studies have shown that, despite the enormous diversity in the structure of locomotor organs and the CNS in different species, locomotor control is based on a few fundamental principles, which can be traced from mollusk to man. The locomotor control system has a multi-level structure. Locomotion is caused by the activity of locomotor organs (legs, wings, fins, trunk, etc.), which generate a propulsive force moving the animal forward. They also serve to support the animal, to maintain a necessary posture, etc. Each of the locomotor organs has its own control mechanism­—a controller. Usually, the activity of locomotor organs is rhythmical as for example in the stepping legs, and this rhythm is generated by individual controllers. Each controller performs a very complex function, i.e., generation of the locomotory rhythm with the sequential activation of different muscle groups of the locomotor organ. In different species, the controllers differ in the role that is played by the central mechanism (central pattern generator, CPG) and sensory feedback. A common feature is that the CPG produces a relatively simple temporal pattern, which is transformed into a more complicated pattern by the neuronal mechanisms constituting the output motor stage of the controller. The activities of the different locomotor organs are coordinated, that is they have a common rhythm and maintain definite phase relations with each other. This coordination is achieved due to the interactions between individual controllers. In many animals, the locomotor organ consists of a number of segments connected by joints (like legs in man or the trunk in fish). The corresponding controllers can, in these cases, be viewed as a number of separate but connected nervous mechanisms, each generating movements of one individual segment around a particular joint. These mechanisms interact with each other, resulting in coordination of movements of individual joints. The activity of locomotor organs can be modified and adapted to the environmental conditions. This is achieved due to sensory feedback supplying individual controllers with information about the current state of the locomotor organs, and about their interaction with the external medium (ground, water). Thus, an individual controller represents a control system with a closed feedback loop. However, in most species, the controller can generate the basic locomotor pattern under open loop conditions. This functional organization of the locomotor control system has been found in animals belonging to very remote branches of the evolutional tree, from mollusks to man, and who exhibit very different forms of locomotion. However, a remarkable diversity has been observed in the concrete solutions for each of the functional blocks (controllers for locomotor organs, system of their interaction, command systems, etc.). In all investigated species, locomotion is initiated by means of an excitatory drive to the controllers of locomotor organs. The vigor of locomotion is proportional to the intensity of this drive. The drive is delivered by a command system. Experiments on simpler animals (mollusk, lamprey) have shown that the command system consists of a number of sub-systems that affect not only the locomotor controllers but also a number of non-locomotor mechanisms. Due to such a design, different gross motor synergies can be formed, and locomotion can be incorporated in different forms of behavior.

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In vertebrates, important components of the command system for the initiation of locomotion are found in different groups of reticulo-spinal neurons. These neurons receive input from the mesencephalic locomotor region and other brain structures involved in the initiation of locomotion, and activate all spinal circuits responsible for the generation of the locomotor pattern. A special system is responsible for the maintenance of balance during locomotion. This system receives information about the orientation of the animal in space via sensory inputs of different modalities (visual, vestibular, somatosensory). It also receives information about the activity of individual controllers. On the bases of this information, the system modifies the activity of controllers and thus affects the movement of locomotor organs, which results in the restoration of balance. A striking similarity has been found between the functional organization of balance mechanisms in swimming and flying animals belonging to phylogenetically remote groups, i.e., in mollusk, locust and lamprey. In all these animals, a deviation from the normal body orientation affects two groups of antagonistic command neurons. These neurons are driven in a reciprocal way by orientation-dependent sensory inputs. The two groups elicit opposite postural corrective responses, and the body orientation at which they are equal will be stabilized. The neural mechanisms for balance control in walking animals are very different from those in swimming and flying animals. They rely to a large extent on somatosensory information, which due to the mechanical interaction of the animal with the ground, well reflects the current orientation of the body and its segments. Balance mechanisms are activated along with the initiation of locomotion. To conclude, studies of locomotion have demonstrated that this complex motor behavior can be easily initiated and controlled by changing only one variable—the level of activity of neurons in the locomotor center. This is due to formation of specific connections (synergies) reducing the number of the degrees of freedom in the locomotor system. Mindy Levin Editor

The Bernstein prize.

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