Publications

Abstract

Prediction of upcoming input is thought to be a main characteristic of language processing (e.g. Altmann & Mirkovic, 2009; Dell & Chang, 2014; Federmeier, 2007; Ferreira & Chantavarin, 2018; Pickering & Gambi, 2018; Hale, 2001; Hickok, 2012; Huettig 2015; Kuperberg & Jaeger, 2016; Levy, 2008; Norris, McQueen, & Cutler, 2016; Pickering & Garrod, 2013; Van Petten & Luka, 2012). One of the main pillars of experimental support for this notion comes from studies that have attempted to measure electrophysiological markers of prediction when participants read or listened to sentences ending in highly predictable words. The N400, a negative-going and centro-parietally distributed component of the ERP occurring approximately 400ms after (target) word onset, has been frequently interpreted as indexing prediction of the word (or the semantic representations and/or the phonological form of the predicted word, see Kutas & Federmeier, 2011; Nieuwland, 2019; Van Petten & Luka, 2012; for review). A major difficulty for interpreting N400 effects in language processing however is that it has been difficult to establish whether N400 target word modulations conclusively reflect prediction rather than (at least partly) ease of integration. In the present exploratory study, we attempted to distinguish lexical prediction (i.e. ‘top-down’ activation) from lexical integration (i.e. ‘bottom-up’ activation) accounts of ERP N400 modulations in language processing.

Abstract

Recognizing other individuals is an essential skill in humans and in other species [1, 2 and 3]. Over the last decade, it has become increasingly clear that person-identity recognition abilities are highly variable. Roughly 2% of the population has developmental prosopagnosia, a congenital deficit in recognizing others by their faces [4]. It is currently unclear whether developmental phonagnosia, a deficit in recognizing others by their voices [5], is equally prevalent, or even whether it actually exists. Here, we aimed to identify cases of developmental phonagnosia. We collected more than 1,000 data sets from self-selected German individuals by using a web-based screening test that was designed to assess their voice-recognition abilities. We then examined potentially phonagnosic individuals by using a comprehensive laboratory test battery. We found two novel cases of phonagnosia: AS, a 32-year-old female, and SP, a 32-year-old male; both are otherwise healthy academics, have normal hearing, and show no pathological abnormalities in brain structure. The two cases have comparable patterns of impairments: both performed at least 2 SDs below the level of matched controls on tests that required learning new voices, judging the familiarity of famous voices, and discriminating pitch differences between voices. In both cases, only voice-identity processing per se was affected: face recognition, speech intelligibility, emotion recognition, and musical ability were all comparable to controls. The findings confirm the existence of developmental phonagnosia as a modality-specific impairment and allow a first rough prevalence estimate.