Monitoring Different Phonological Parameters of Sign Language Engages the Same Cortical Language Network but Distinctive Perceptual Ones 1,2 1,3 1,4 2 Velia Cardin *, Eleni Orfanidou *, Lena Kästner , Jerker Rönnberg , Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/28/1/20/1784314/jocn_a_00872.pdf by MIT Libraries user on 17 May 2021 Bencie Woll1, Cheryl M. Capek5, and Mary Rudner2 Abstract ■ The study of signed languages allows the dissociation of tested: deaf native signers, deaf nonsigners, and hearing non- sensorimotor and cognitive neural components of the language signers. Results show that the linguistic processing of different signal. Here we investigated the neurocognitive processes under- phonological parameters of sign language is independent of the lying the monitoring of two phonological parameters of sign sensorimotor characteristics of the language signal. Handshape languages: handshape and location. Our goal was to determine and location were processed by different perceptual and task- if brain regions processing sensorimotor characteristics of dif- related brain networks but recruited the same language areas. ferent phonological parameters of sign languages were also The semantic content of the stimuli did not influence this pro- involved in phonological processing, with their activity being cess, but phonological structure did, with nonsigns being asso- modulated by the linguistic content of manual actions. We con- ciated with longer RTs and stronger activations in an action ductedanfMRIexperimentusing manual actions varying in observation network in all participants and in the supramarginal phonological structure and semantics: (1) signs of a familiar sign gyrus exclusively in deaf signers. These results suggest higher language (British Sign Language), (2) signs of an unfamiliar sign processing demands for stimuli that contravene the phonological language (Swedish Sign Language), and (3) invented nonsigns rules of a signed language, independently of previous knowledge that violate the phonological rules of British Sign Language and of signed languages. We suggest that the phonological charac- Swedish Sign Language or consist of nonoccurring combinations teristics of a language may arise as a consequence of more effi- of phonological parameters. Three groups of participants were cient neural processing for its perception and production. ■ INTRODUCTION content. Our main goal was to determine if brain regions Valuable insights into the neuroanatomy of language and involved in processing sensorimotor characteristics of the cognition can be gained from the study of signed lan- language signal were also involved in phonological process- guages. Signed languages differ dramatically from spoken ing, with their activity being modulated by the linguistic languages with respect both to the articulators (the content of manual actions. hands vs. the vocal tract) and to the perceptual system The semantic purpose of language—the sharing of supporting comprehension (vision vs. audition). However, meaning—is similar across signed and spoken languages. linguistically (Sutton-Spence & Woll, 1999), cognitively However, the phonological level of language processing (Rudner, Andin, & Rönnberg, 2009), and neurobiologically may be specifically related to the sensorimotor character- (Corina, Lawyer, & Cates, 2012; MacSweeney, Capek, istics of the language signal. Spoken language phonology Campbell, & Woll, 2008; Söderfeldt, Rönnberg, & Risberg, relates to sound patterning in the sublexical structure of 1994), there are striking similarities. Thus, studying signed words. Sign language phonology relates to the sublexical languages allows sensorimotor mechanisms to be disso- structure of signs and in particular the patterning of ciated from cognitive mechanisms, both behaviorally and handshape, hand location in relation to the body, and hand neurobiologically. movement (Emmorey, 2002). Phonology is generally con- In this study, we investigated the neural networks under- sideredtobearbitrarilyrelatedtosemantics.Insigned lying monitoring of the handshape and location (two languages, however, phonology is not always indepen- phonological components of sign languages) of manual dent of meaning (for an overview, see Gutiérrez, Williams, actions that varied in phonological structure and semantic Grosvald, & Corina, 2012), and this relation seems to influ- ence language processing (Grosvald, Lachaud, & Corina, 1University College London, 2Linköping University, 3University of 2012; Thompson, Vinson, & Vigliocco, 2010) and its neural Crete, 4Humboldt-Universität zu Berlin, 5University of Manchester underpinning (Rudner, Karlsson, Gunnarsson, & Rönnberg, *These authors contributed equally to this study. 2013; Gutiérrez, Müller, Baus, & Carreiras, 2012). © 2015 Massachusetts Institute of Technology Journal of Cognitive Neuroscience 28:1, pp. 20–40 doi:10.1162/jocn_a_00872 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/jocn_a_00872 by guest on 27 September 2021 Speech-based phonological processing skill relies on itoring of location relates to the tracking of visual objects mechanisms whose neural substrate is located in the in space and in relation to equivalent positions relative to posterior portion of the left inferior frontal gyrus (IFG) the viewer’s body. As such, it is expected that extraction of and the ventral premotor cortex (see Price, 2012, for a the feature of location will recruit dorsal visual areas, review). The posterior parts of the junction of the parie- which are involved in visuospatial processing and visuo- tal and temporal lobes bilaterally (Hickok & Poeppel, motor transformations (Ungerleider & Haxby, 1994; Milner 2007), particularly the left and right supramarginal gyri & Goodale, 1993), and resolve spatial location of objects. (SMG), are also involved in speech-based phonology, Parietal areas involved in the identification of others’ activating when participants make decisions about the body parts (Felician et al., 2009) and those involved in Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/28/1/20/1784314/jocn_a_00872.pdf by MIT Libraries user on 17 May 2021 sounds of words (i.e., their phonology) in contrast to self-reference, such as medial prefrontal, anterior cingulate, decisions about their meanings (i.e., their semantics; and precuneus, could also be involved in the extraction of Hartwigsen et al., 2010; Devlin, Matthews, & Rushworth, this feature (Northoff & Bermpohl, 2004). 2003; McDermott, Petersen, Watson, & Ojemann, 2003; Handshape refers to contrastive configurations of the Price, Moore, Humphreys, & Wise, 1997). fingers (Sandler & Lillo-Martin, 2006). It has been shown The phonology of sign language is processed by left- that deaf signers are faster and more accurate than hear- lateralized neural networks similar to those that support ing nonsigners at identifying handshape during a moni- speech phonology (MacSweeney, Waters, Brammer, toring task and that lexicalized signs are more easily Woll, & Goswami, 2008; Emmorey, Mehta, & Grabowski, identified than nonlexicalized signs (Grosvald et al., 2007), although activations in the left IFG are more ante- 2012). In terms of lexical retrieval, handshape seems to rior for sign language (Rudner et al., 2013; MacSweeney, play a greater role in later stages than location (Gutiérrez, Brammer, Waters, & Goswami, 2009; MacSweeney, Müller, et al., 2012), possibly by constraining the set of Waters, et al., 2008). Despite these similarities, it is not activated lexical items. From a perceptual point of view, clear to what extent the processing of the specific phono- monitoring of handshape is likely to recruit ventral visual logical parameters of sign languages, such as handshape, and parietal areas involved in the processing of object location, and movement, recruits functionally different categories and forms—in particular regions that respond neural networks. Investigation of the mechanisms of sign more to hand stimuli than to other body parts or objects, phonology have often focused separately on sign hand- such as the left lateral occipitotemporal cortex, the extra- shape (Andin, Rönnberg, & Rudner, 2014; Andin et al., striate body area, the fusiform body area, the superior 2013; Grosvald et al., 2012; Wilson & Emmorey, 1997) parietal lobule, and the intraparietal sulcus (Bracci, and sign location (Colin, Zuinen, Bayard, & Leybaert, Ietswaart, Peelen, & Cavina-Pratesi, 2010; Op de Beeck, 2013; MacSweeney, Waters, et al., 2008). Studies that have Brants, Baeck, & Wagemans, 2010; Vingerhoets, de Lange, compared these two phonological parameters identified Vandemaele, Deblaere, & Achten, 2002; Jordan, Heinze, differences in comprehension and production psycho- Lutz, Kanowski, & Jancke, 2001; Alivesatos & Petrides, linguistically (e.g., Orfanidou, Adam, McQueen, & Morgan, 1997; Ungerleider & Haxby, 1994; Milner & Goodale, 1993). 2009; Carreiras, Gutiérrez-Sigut, Baquero, & Corina, 2008; Motor areas processing specific muscle–skeletal config- Dye & Shih, 2006; Emmorey, McCullough, & Brentari, urations are also likely to be recruited (Hamilton & 2003), developmentally (e.g., Morgan, Barrett-Jones, & Grafton, 2009; Gentilucci & Dalla Volta, 2008). Thus, it Stoneham, 2007; Karnopp, 2002; Siedlecki & Bonvillian, is likely that different networks will be recruited for the 1993), and neuropsychologically (Corina, 2000). In particu- perceptual and motoric processing of these phonologi- lar, the neural signature of handshape