A study was carried out to investigate the correlation between sleep apnea frequency, blood oxygenation and neurological condition in 21 infants at six weeks of age with inconspicuous medical history. Polygraphic recordings of respiratory behaviour and transcutaneous blood gas monitoring lasted for at least five hours. To quantify the results of the neurological examination we established a neurological optimality score (NOS). We found statistically significant correlations between several indexes of apneas and indexes of blood oxygenation and NOS. Thus, a reduced NOS was strongly correlated with higher apnea frequencies and with pronounced drops of transcutaneous PO2-values. In addition all but one infant who were diagnosed as having a sleep apnea syndrome showed a greater than ten percent reduction of NOS. Some pathophysiological considerations to explain our findings are put forward and the possible role of the neuromodulator adenosine is emphasized.