Acoustically evoked responses in premature and full term newborn infants

Maturational Changes in the Auditory System as Reflected in Human Brainstem Evoked Responses

“…Our threshold estimation in newborns confirmed earlier reports, lay below 30 dB (HL) and should be close to that of the adult [10,20,37], The threshold for auditory responsivity obtained by this ABR method is considerably lower than that obtained by re cording auditory cortical evoked potentials [3][4][5] or by behavioral tests. Behavioral au ditory studies are in most cases unquantitative since it is hard to separate the interaction of various components of the nervous sys tem.…”

“…The intensity series seem to confirm that the ef fect of signal intensity on the latency of ABRs is most likely due to immaturity of peripheral auditory mechanisms, since central transmis sion time is unaffected at different intensity levels. Our intensity series versus chronolog ical age showed, as compared with earlier studies, a remarkable agreement between these data and suggested that the maturation of the neural substrate for the ABR pro ceeded in essentially the same way in all new borns and infants [3,37,38].…”

Maternal Toxemia, Fetal Malnutrition and Bioelectric Brain Activity of the Newborn

“…However, a strong correlation of r = 0,68 on the 1st and 2nd day and of r = 0,99 on the 5th day exists between the glucose oxidase and the hexokinase method (unpublished data obtained in our laboratory by H. WOLF). The values obtained with the hexokinase method, in which true glucose in determinded, are always a little higher (BACHMANN 1969) than with the glucose oxidase method after uranyl acetate deproteinization. Therefore the glutathione contamination does not influence the conclusions drawn from our data: None of our study infants in fact had symptomatic hypoglycemia.…”

“…Neurological studies of motor behaviour (SAINT-ANNE DARGASSIES 1955, 1966, AMIEL-TISON 1968, BRETT 1965, ROBINSON 1966, GRAZIANI et al 1968), the electroencephalogram (DREYFUS-BRISAC 1964, cortical evoked responses (ENGEL and BENSON 1968, GRAZIANI et al 1968, AKIYAMA et al 1969, and nerve conduction velocity , RUPPERT and JOHNSON 1968, DUBOWITZ et al 1968) have led to the concept that fetal brain development is dependent on conceptional age rather than on body weight. Basically this concept is correct and well supported by anatomi-cal studies (LARROCHE 1962).…”

Activity states in premature and term infants

“…Innumerable investigators have mapped the development of the nervous system in the premature infant. Their measures have included not only behavioral and neurological examinations (Dubowitz, Dubowitz, & Goldberg, 1970;Finnstrom, 1971 ;Robinson, 1966;Saint-Anne Dargassies, 1966), but also EEG patterns (Dreyfus-Brisac, 1970;Goldie, Svedsen-Rhodes, Easton, & Roberton, 1971 ;Parmelee, Schulte, Akiyama, Wenner, Schultz, & Stern, 1968), auditory and visual evoked potentials (Akiyama, Schulte, Schultz, & Parmelee, 1969;Ellingson, 1960;Engel & Butler, 1963;Graziani, Weitzman, & Velasco, 1968;Monod & Garma, 1971;Weitzman & Graziani, 210 MICHAELIS ET AL. 1968), peripheral nerve conduction velocity (Blom and Finnstrom,197 1, Dubowitz, Whittaker, Brown, & Robinson, 1968;Schulte, Michaelis, Linke, & Nolte, 1968), and brain weight (Larroche, 1962).…”