PubMed · 10466721
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
F Baumgart, B Gaschler-Markefski, M G Woldorff, H J Heinze, H Scheich. 1999-08-19. A movement-sensitive area in auditory cortex.. https://doi.org/10.1038/23390
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Language and learning disabilities occur in almost half of individuals with oral clefts. The characteristics of these cognitive dysfunctions vary according to the cleft type, and the mechanisms underlying the relation between cleft type, cognitive dysfunction, and cleft-caused middle-ear disease are unknown. This study investigates preattentive auditory discrimination, which plays a significant role in language acquisition and usage, in infants with different cleft types. A mismatch negativity (MMN) component of brain evoked potentials, which indexes preconscious sound discrimination, and brain responses to rare sine-wave tones were recorded in 12 healthy infants and 32 infants with oral clefts at the ages of 0 and 6 months. Infants with clefts were subdivided into two categories: those with cleft lip and palate (CLP) (n=11 at birth, n=6 at the age of 6 months) and those with cleft palate only (CPO) (n=17 at birth, n=8 at the age of 6 months). At both ages, brain responses to rare sounds tended to be smaller in both cleft subgroups than in healthy peers. However, in the latency range of 300 to 500 ms, the MMN was significantly smaller in infants with CPO. In infants with CLP, the MMN was comparable to that of healthy infants. Differences in auditory discrimination between infants with CLP and CPO, as reflected by MMN, were detectable at birth and persisted into later infancy. This pattern parallels known behavioural differences between children with these cleft types. Brain responses to rare sounds, in contrast, had no differentiative power with respect to the cleft type.
Studies based on whole-head MEG recordings are providing more and more impressive results. In such recordings, the MEG sensors are several centimeters away from the scalp and the positions of the MEG sensors with respect to the head differ from subject to subject, and from session to session for the same subject. In this paper, a method is presented and tested to estimate the scalp MEG distributions from whole-head MEG measurements. The goal is to remove the discrepancy of MEG measurements caused by the various sensor positions with respect to the head, as well as to reduce the smearing effect caused by the distance of the MEG sensors from the scalp. The MEG measurement was first projected to a hypothetical dipole layer within the head volume conductor model using the inverse solution. The scalp MEG estimation was then obtained from the resultant dipole layer by the forward solution. The results from simulation studies, phantom experiments, and the auditory evoked field analysis demonstrated that, with reasonable signal to noise ratios, this method is a feasible way to achieve our goals.
Explore the source record for details and available documents.