This paper investigates the relationship between speech perception and 
linguistic experience in Kaqchikel, a Mayan language of Guatemala. Our 
empirical focus is the perception of stop consonants (plain, ejective, 
and implosive) in this language. Drawing on an AX discrimination task, a 
corpus of spontaneous spoken Kaqchikel, and a novel text corpus, we make 
two claims. First, we argue that speech perception is mediated by 
phonemic representations which include rich acoustic detail drawn from 
prior phonetic experience, as in Exemplar Theory. Second, segment-level 
distributional patterns also condition speech perception: the perceptual 
distinctiveness of a given pair of phonemes is affected by their 
functional load as well as their overall contextual predictability. 
These factors have an effect on discrimination even for relatively fast 
response times, suggesting that top-down effects of linguistic 
experience may occur quite early in the timecourse of speech processing. 
We take this result to indicate that distributional fac- tors like 
functional load may affect speech perception by shaping low-level 
perceptual tuning during linguistic development. This study replicates 
and extends some key findings in speech perception in the context of a 
language (Kaqchikel) which is both structurally and sociolinguistically 
different from the majority languages (like English) which have served 
as the basis of most work in the speech perception literature. At the 
practical level, our research provides an illustration of some methods 
for conducting corpus-based laboratory phonology with lesser-studied and 
under-resourced languages.