Abstract/Details

Auditory processing of complex tones in newborn infants


2010 2010

Other formats: Order a copy

Abstract (summary)

Pitch extraction from complex acoustic stimuli during neonatal period in infants was examined in this study. It is one of the most fundamental auditory processes. Pitch processing is crucial for speech intonation and musical melody perception. Preferences of newborns for “motherese” (or infant directed speech), which has different pitch characteristics compared to adult directed speech, suggest an early pitch information processing capability in newborns. Although auditory functional development in the auditory system at early ages draws much attention of researchers from different disciplines, the number of studies during the neonatal period is limited. We first asked how pitch information processing develops. It was hypothesized that newborns already possess ability to process pitch information early during perinatal period. Second, we hypothesized that the extraction of pitch information in acoustic stimuli depended on the integrity of the auditory pathway. Brain insult in the perinatal period has been shown highly likely to affect subcortical structures, including the auditory brainstem and midbrain, through different mechanisms. We reasoned that if there were delays in or problems with pitch processing in brain-injured or premature neonates when compared to healthy or premature infants of equal gestation, then, in the absence of peripheral disturbances, evidence for CNS mediation of the development of pitch processing could be argued.

Two types of auditory brainstem responses were studied: (1) auditory brainstem evoked responses (ABRs) to click stimuli, and (2) the frequency following response (FFR) to complex tones were utilized to study the above questions in N=128 premature and term infants assigned to the Neonatal Intensive Care Unit (NICU) at birth, all at varying risk for a CNS injury (mean gestational age at birth=34±3.6 weeks).

In summary, we confirmed that auditory pitch information processing of complex sound was present in newborn infants as early as 32 weeks gestation. Neonatal FFR studies provided positive evidence of responses to the pitch-related information both in the envelope-related frequency as well as in the difference tone and stimulus component-related frequencies. Similar responses at younger and older ages at test indicated that this capability remains stable across age during the first month of life. Moreover, NICU infants with evidence of a structural perinatal brain injury showed impairment in this type of auditory processing.

Indexing (details)


Subject
Neurosciences;
Neurobiology
Classification
0317: Neurosciences
0421: Neurobiology
Identifier / keyword
Biological sciences; Auditory evoked responses; Auditory processing; Complex tones; Frequency following response; Newborn infants; Perinatal brain injury; Pitch
Title
Auditory processing of complex tones in newborn infants
Author
Phan, Ha Thi Thu
Number of pages
125
Publication year
2010
Degree date
2010
School code
0046
Source
DAI-B 71/12, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9781124290584
Advisor
Karmel, Bernard Z.
Committee member
Long, Glenis R.; Ma, Pokay; Parab, Santosh; Trenkner, Ekkhart; Wieraszko, Andrzej
University/institution
City University of New York
Department
Biology
University location
United States -- New York
Degree
Ph.D.
Source type
Dissertations & Theses
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
3426804
ProQuest document ID
763425523
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
http://search.proquest.com/docview/763425523
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.