In December 2002, he was awarded a prestigious ‘vernieuwingsimpuls’ grant from Netherlands Organization for Scientific Research and as of March 2004 he is Professor of Psycholinguistics at Maastricht University. In 2000 he became an academy researcher of the Royal Netherlands Academy of Arts and Sciences, working in the Faculty of Psychology at Maastricht University and at the Max Planck Institute for Psycholinguistics.

He then worked as a Postdoctoral Fellow in the Cognitive Neuropsychology Laboratory of the Psychology Department at Harvard University, where he carried out psycholinguistic and neuropsychological research. in psychology from the University of Nijmegen, Netherlands, in 1997.

from the University of Trier, Germany, in 1994 and his Ph.D. intelligibility, comprehensibility, severity) need to be clearly defined and methodologies described in sufficient details to allow for replication, cross-comparisons/meta-analyses and pooling of data. vowel and consonant reductions) and to gather normative data from a large number of healthy speakers. There is still extensive research to be carried out to identify relevant acoustic combinations that could account for perceived speech variations (e.g. To date, no acoustic measure is able to predict speech intelligibility to a large extent. To conclude, as speech is highly variable even in healthy adult speakers, a better understanding of the imprecisions in healthy spontaneous speech will provide a more realistic baseline for the investigation of disordered speech. The following measures were shown to be linked to sub-lexical perceived speech intelligibility ratings: for vowels, steady-state F1 and F2 measures, the F1 range, the - F2 difference, F0-F1 and F1-F2 differences in and, the vowel space area, the mean amount of formant movement, the vector length and the spectral change measure for consonants, the centroid energy and the spectral peak in the -sound, as well as the steady-state F1 offset frequency in vowels preceding and. Various spectral measures and intelligibility estimates were used.

Eighteen papers investigated vowel acoustics, one studied glides and eight articles investigated consonants, mostly sibilants. This study aims to systematically review original articles investigating the link between spectral acoustic measures in healthy talkers and perceived speech intelligibility, according to the PRISMA guidelines.

Encoding in speech