Using the Movement-Related Cortical Potential to Study Motor Skill Learning (Fragment)

By: David J. Wright, Paul S. Holmes, Dave Smith Institute for Performance Research, Manchester Metropolitan University, Crewe, England. ABSTRACT. The movement-related cortical potential (MRCP) is a low-frequency negative shift in the electroencephalographic recording that occurs about 2 s before voluntary movement production. The MRCP is thought to reflect the cortical processes involved in movement planning and movement preparation. In recent years, researchers have used this potential to investigate the processes involved in motor skill learning. Their findings indicate differences in the amplitude and onset times of the MRCP between experienced and novice performers, which have been attributed to long-term training in the experts. The authors discuss these findings critically and consider their implications for both future research and practice. Keywords: ecological validity, electroencephalography, motor planning, motor preparation, neural efficiency A motor skill is an action that requires the voluntary movement of the body or a limb to achieve a specific goal (Magill, 2003). Motor skill learning is the process associated with practice or experience that leads to a relatively permanent change in a performer’s ability to perform the motor skill (Schmidt & Lee, 2005). The learning of motor skills is fundamental to human development and is generally measured by recording levels of performance at a particular skill over a period of time (Magill). Despite the importance of motor skill learning in human development, the cortical processes involved in motor skill learning are not yet fully understood. Research using neuroscientific techniques such as electroencephalography (EEG) may allow researchers to obtain a greater understanding of the processes involved in motor skill learning and may also offer a more objective marker for determining whether learning has occurred, rather than relying solely on performance measures. The movement-related cortical potential (MRCP), a type of event-related potential, was first discovered by Kornhuber and Deecke (1964, 1965). It is a low-frequency (around 0–5Hz) negative shift in the EEG recording that occurs about 1.5–2 s before the onset of voluntary movement. Negativity in the EEG has been related to increased synaptic activity, whereas positivity in the EEG has been related to synaptic inactivity in the cortical area under study (Deecke, 1996). Therefore, the negative profile of the MRCP is indicative of an increase in cortical synaptic activity prior to movement production. The amplitude and the onset time of the premovement components of the MRCP are known to vary depending on the physical and psychological characteristics of the forthcoming movement (Birbaumer, Elbert, Canavan, & Rockstroh, 1990). As such, the two premovement components of the MRCP, called the readiness potential (RP) and negative slope (NS), respectively, may reflect the cortical processes involved in the planning of and preparation for voluntary movement (Shibasaki & Hallett, 2006)1. The amplitude of the negativity is often interpreted by researchers as an indication of the amount of energy or effort that is required to plan the performance of the forthcoming movement (Lang, Beisteiner, Lindinger, & Deecke, 1992). Similarly, the onset time of the MRCP may indicate the length of time taken to plan and prepare the movement (e.g., Tarkka & Hallett,1990). In recent years, several studies have investigated the MRCP prior to motor skill performance with the aim of establishing how the MRCP may be influenced by (a) the skill level of the performer and (b) skill learning. In this review, we examine these studies, raise awareness of the use of the MRCP as a potential objective marker of skill learning, and suggest possible future avenues of research in the area.