Author/Authors :
Plamenka Nanova، نويسنده , , Laura Lyamova، نويسنده , , Maria Hadjigeorgieva، نويسنده , , Vasil Kolev، نويسنده , , Juliana Yordanova، نويسنده ,
Abstract :
Objectives
The aim of the present study was to evaluate the effects of gender on sensory and cognitive information processing in children by analyzing auditory event-related potentials (ERPs). The major questions were: (1) do ERPs differ between girls and boys aged 7–10 years, (2) do gender differences in ERPs depend on the development with age, on task-processing demands, and on the development of neuroelectric networks as reflected by the spontaneous EEG?
Methods
Thirty-six healthy children (18 girls and 18 boys) were divided in two age groups (7- to 8- and 9- to 10-year-old). Boys and girls were pairwise matched for age. Auditory ERPs were analyzed in a passive listening condition (PLC), a simple reaction task (SRT) and a serial learning reaction task (SLRT), in which memory and sensorimotor processes were varied in a balanced way. Cognitive performance, reaction times (RTs), and the spontaneous electroencephalogram (EEG) were also measured.
Results
Cognitive performance improved earlier in girls than boys, whereas response speed was not affected by gender. Independent of processing demands, ERP components within 300 ms after stimulation (N1, P2, N2 and P3) increased with development only in the group of girls. For later components, the developmental speeding of the parietal P3b component to task-relevant stimuli also tended to be more expressed in girls than boys, whereas a late frontal negative wave N400–700 was shorter in the girls than boys from the two age groups. Likewise, independently of age, the spontaneous EEG manifested a larger theta activity in girls than boys.
Conclusions
Developmental changes of basic auditory processing mechanisms strongly depend on gender in children between 7 and 10 years by being faster in girls. This gender-specific development of early ERP components is not modulated by processing demands, cannot be attributed to a faster cognitive maturation of girls, nor can it be explained with the gender-specific maturation of background neuroelectric networks. Rather, it reflects an accelerated functional activation of auditory processing networks in girls. Interestingly, the cognitive development was also faster in girls, but it occurred earlier than the functional activation of auditory processing networks.
Significance
This study provides evidence for accelerated neuroelectric (as reflected by spontaneous EEG), neurofunctional (as reflected by auditory ERPs), and neurocognitive (as reflected by learning performance) development in 7- to 10-year-old girls than boys.
Keywords :
event-related potentials , EEG , Gender , children , Cognitive processing