Some of the causes in children for Dark circles under eyes in children may include: 1  Lack of sleep. 2  Nasal congestion. 3  Black eye due to trauma.  Frequent eye 1  rubbing. Hayfever.  Inherited 1  trait. Dehydration. 2  Allergies. 3  Eczema. Phenol sulfotransferase deficiency.
From From P300 Development across the Lifespan: A Systematic Review and Meta-Analysis. The latency and amplitude of the P300 response may vary as a function of age. The P300 (P3) wave is an event related potential (ERP) component elicited in the process of decision making.pplications in brain-computer interfacing (BCI) have also been proposed. The P300 has a number of desirable qualities that aid in implementation of such systems. First, the waveform is consistently detectable and is elicited in response to precise stimuli.
P Wave. The P wave represents atrial depolarization. In a normal EKG, the P-wave precedes the QRS complex. It looks like a small bump upwards from the baseline. The amplitude is normally 0.05 to 0.25mV (0.5 to 2.5 small boxes).Normal duration is 0.06-0.11 seconds (1.5 to 2.75 small boxes).The shape of a P-wave is usually smooth and rounded.t looks like a small bump upwards from the baseline. The amplitude is normally 0.05 to 0.25mV (0.5 to 2.5 small boxes). Normal duration is 0.06-0.11 seconds (1.5 to 2.75 small boxes). The shape of a P-wave is usually smooth and rounded.