Resumen:
The sensorimotor rhythm (SMR) is an electroencephalographic
rhythm associated with motor and cognitive development observed in the central brain regions during wakefulness in the absence of movement, and it reacts contralaterally to generalized and hemibody movements. The purpose of this work was to characterize the SMR of 4-month-old infants, born either healthy at term or prematurely with periventricular leukomalacia (PVL). Two groups of infants were formed: healthy and premature with PVL. Their electroencephalograms (EEGs) were recorded in four conditions: rest, free movement, right-hand grasping and left-hand grasping, in order to explore general reactivity to free movement and contralateral reactivity in hand-grasping conditions. Associations between SMR,
and cognitive and motor performance were analyzed. The healthy infants showed a SMR between 5.47 and 7.03 Hz,
with clear contralateral reactivity to free movement and
right-hand grasping. However, the premature infants with
PVL did not show enough electroencephalographic characteristics to evidence the presence of SMR. Poor performance, characteristic of children with PVL, was related to
low-frequency SMR, while good performance was associated
with a higher frequency rhythm in the left hemisphere.
The presence of SMR in the group of healthy infants could
be considered a sign of health at this age. Thus, poor SMR
evidence in the EEG of infants with PVL is probably a
sign of brain immaturity or brain dysfunction. Our results
provide data on infant SMR development that is needed to
design neurofeedback protocols for infants with PVL.