Novak G P, Kurtzberg D, Kreuzer J A, Vaughan H G
Rose F. Kennedy Center for Research in Mental Retardation and Human Development, Albert Einstein College of Medicine, Bronx, NY 10461.
Electroencephalogr Clin Neurophysiol. 1989 Oct;73(4):295-305. doi: 10.1016/0013-4694(89)90108-9.
Cortical auditory evoked potentials (AEPs) to the synthesized syllables [da[ and [ta[ and to the isolated 3 formants of [da[ were obtained from 32 normal infants studied at monthly intervals from birth through 3 months and at 6 months of age. A bilateral array of 16 electrodes referenced to the mid-occiput permitted a topographic analysis of the cortical AEPs at selected latencies. A differential maturational sequence was seen: a predominantly negative cortical AEP wave form became positive, first over the frontocentral region (around term), and then over the temporal region (at 1-2 months). The timing of these electrophysiological changes coincides with a differential anatomical maturational sequence in the auditory cortex, as myelination and synaptogenesis are more advanced in primary than secondary auditory areas at term. All infants in this study followed this developmental sequence. However, there was no systematic effect of the center frequency of the formant stimuli on the maturational level of their respective cortical AEPs, suggesting a relative maturational equivalence in those regions of auditory cortex responding to stimuli across the frequency range present in human speech. In term infants, an initial midline positivity and bitemporal negativities were asynchronous in their peak and offset latencies. suggesting independent generators for each of these components. In infants from 3 to 6 months of age, cortical AEP wave forms consisted of 2 initial positive peaks followed by a negative peak. While the wave forms were similar over midline and lateral scalp, spatiotemporal analysis revealed differences in the latency of onset, duration and in the spatial extent of these components, again suggesting that 2 bilateral, temporally overlapping generators contribute to the cortical AEP. No systematic topographic difference was observed in the cortical AEPs elicited by each of the 3 formants, which differed in center frequencies.
对32名正常婴儿进行研究，从出生到3个月每月进行一次检查，6个月时也进行检查，获取了他们对合成音节[da]和[ta]以及对[da]的分离的3个共振峰的皮质听觉诱发电位（AEP）。以枕骨中部为参考的双侧16电极阵列允许对选定潜伏期的皮质AEP进行地形图分析。观察到一种不同的成熟序列：一种主要为负的皮质AEP波形变为正的，首先在额中央区域（足月左右），然后在颞区（1 - 2个月时）。这些电生理变化的时间与听觉皮层中不同的解剖成熟序列一致，因为在足月时初级听觉区域的髓鞘形成和突触发生比次级听觉区域更先进。本研究中的所有婴儿都遵循这种发育序列。然而，共振峰刺激的中心频率对其各自皮质AEP的成熟水平没有系统影响，这表明在听觉皮层中对人类语音中存在的整个频率范围内的刺激做出反应的那些区域具有相对成熟等效性。在足月婴儿中，最初的中线正性波和双侧颞部负性波在其峰值和偏移潜伏期是不同步的，这表明这些成分各自有独立的发生器。在3至6个月大的婴儿中，皮质AEP波形由2个初始正峰后跟一个负峰组成。虽然中线和头皮外侧的波形相似，但时空分析显示这些成分在起始潜伏期、持续时间和空间范围上存在差异，这再次表明2个双侧、时间上重叠的发生器对皮质AEP有贡献。由3个中心频率不同的共振峰各自诱发的皮质AEP中未观察到系统的地形图差异。
