title: Effects of acoustic complexity on processing sound intensity in 10- to 11-year-old children: evidence from cortical auditory evoked potentials.
abstract: OBJECTIVE
  The environmental complexity that sounds are presented in, as well as the stimulus presentation rate, influences how sound intensity is centrally encoded with differences between children and adults.
  
  
  METHODS
  Cortical auditory evoked potential (CAEP) comparison study in children and adults examining two stimulus rates and three different stimulus contexts.
  
  
  METHODS
  Twelve 10 and 11 year olds and 11 adults were studied in two experiments examining the CAEP to a 1-KHz, 50-ms tone. A Slow-Rate experiment at 750-ms stimulus onset asynchrony (SOA) compared the CAEPs of 78 dB to 86 dB SPL in 2 complexity conditions. A Fast-Rate experiment was performed at 125 ms SOA with the same conditions plus an additional complexity condition. Repeated measures and mixed-model analysis of variance (ANOVA) was used to examine the latency and amplitude of the CAEP components.
  
  
  RESULTS
  CAEP amplitudes and latencies were significantly affected by rate, intensity, and age with complexity interacting in multiple mixed-mode ANOVAs. P1 was the only CAEP component present at the Fast Rate. There were main effects of rate, age, and stimulus intensity level on the CAEP amplitudes and latencies. Maturational differences were seen in the interactions of intensity with complexity for the different CAEP components.
  
  
  CONCLUSIONS
  Complexity of the sound environment was reflected in the relative amplitude of the CAEPs evoked by sound intensity. The effect of stimulus intensity depended on the complexity of the surrounding environment. Effects of the surrounding sounds were different in children than in adults.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Bronx, New York 10467, USA. edinces@montefiore.org
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Dinces
authors.forename: Elyse
authors.initials: E
authors.lastname: Sussman
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001307:Auditory Perception; D002648:Child; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time