Motor learning can be monitored by observing the development of neural correlates of error processing. Among these neural correlates, the error- and feedback-related negativity (Ne/ERN and FRN) represent error processing mechanisms. While the Ne/ERN is more related to error prediction, the FRN is found after an error is manifested. The questions the current study strives to answer are: What information is needed by the system to make error predictions and how is this represented by the Ne/ERN and FRN in a complex motor task? We reduced the information and increased the difficulty level for the prediction in a semivirtual throwing task and found no Ne/ERN but a large FRN when the action result was finally observed (hitting or missing a target). We assume that uncertainty for error prediction was too high (either due to insufficient information or due to lacking prerequisites for prediction), such that error processing had to be mainly based on feedback. The finding is in line with the reinforcement theory of learning, after which Ne/ERN and FRN should behave complementary.
Michael Joch, Mathias Hegele, Heiko Maurer, Hermann Müller and Lisa K. Maurer
Rachel E. Klaren, Elizabeth A. Hubbard, Weimo Zhu and Robert W. Motl
This brief research note examined the reliability of scores from an accelerometer as measures of sedentary and physical activity behaviors in persons with multiple sclerosis (MS). The analysis was performed on a combined data set from 2 previous longitudinal investigations of physical activity in MS. We focused on the number of days required to reliably estimate sedentary behavior, based on time spent in sedentary behavior per day and number of sedentary breaks, number of long sedentary bouts, and average length of sedentary bouts per day. We further examined the number of days required to reliably estimate physical activity behavior, based on time spent in light and moderate-to-vigorous physical activity and average length of activity bouts per day. Between 4–6 days of monitoring and 3–7 days of monitoring were necessary for good reliability of scores from all sedentary outcomes and physical activity outcomes, respectively. These results should guide research and practice examining sedentary and physical activity behaviors using accelerometry in persons with MS.
Renata Valle Pedroso, José Maria Cancela, Carlos Ayán, Angelica Miki Stein, Gilson Fuzaro, José Luiz Riani Costa, Francisco J. Fraga and Ruth Ferreira Santos-Galduróz
for P300 measurement were placed on the scalp at frontal (Fz), central (Cz), and parietal (Pz) midlines. For vertical and horizontal eye movement monitoring, 2 electrodes (bipolar montage) were positioned above the right eyebrow and next to the left eye, respectively, vertically and horizontally
Nicola D. Ridgers, Karen E. Lamb, Anna Timperio, Helen Brown and Jo Salmon
time due to a lack of movement. Monitors that are capable of assessing changes in posture (eg, activPAL) should be used in future experimental studies. Third, the restriction of LPA and MVPA condition was shorter in duration than the additional LPA and MVPA conditions due to the scheduling of recess