Transient infant movements (TIM): frequent infant non-pathological developmental motor phenomena

Lombroso and Fejerman, in 1977, described non-epileptic movements in normal infants and named them "benign myoclonus of early infancy", which were recently relabelled by Fernandez-Alvarez as "benign polymorphous movement disorder of infancy" (BPMDI). The focus of our study was to describe, categorize and point out the peculiar clinical representations of these heterogeneous phenomena through our video footage, particularly to those less experienced in paediatric neurology. We included all infants with a video-EEG performed at our unit or a home video recording of "Fejerman-Lombroso", "benign myoclonus of early infancy", "shuddering attacks" or "paroxysmal non-epileptic movements". Twenty-one children were selected. Age at onset ranged between two and 13 months, age at disappearance ranged between seven and 16 months, age at recording ranged between four and 16 months, and duration of the phenomena ranged between two weeks and 19 months. In total, 85% infants had normal neurodevelopment at onset and follow-up (mean follow-up: 31.47 months) and 15% presented with neuropsychological or neurosensory deficits. We distinguished four different patterns of movements: movement of the head in 50%, shuddering attacks in 30%, tonic brief contractions of the trunk and limbs in 10%, and elevation of the shoulders in 10%. These motor phenomena do not affect neurological status and are not associated with developmental delay. Considering that clinical interpretation may be challenging, especially relative to epileptic seizures, we present an explanatory video of these characteristic events. We also propose a new definition that is simple to remember: "transient infant movements" (TIM).