Grammatical workspace sharing during language production and language comprehension: Evidence from grammatical multitasking

Abstract

Grammatical encoding and grammatical decoding (in sentence production and comprehension, respectively) are often portrayed as independent modalities of grammatical performance that only share declarative resources: lexicon and grammar. The processing resources subserving these modalities are supposed to be distinct. In particular, one assumes the existence of two workspaces where grammatical structures are assembled and temporarily maintained—one for each modality. An alternative theory holds that the two modalities share many of their processing resources and postulates a single mechanism for the online assemblage and short-term storage of grammatical structures: a shared workspace. We report two experiments with a novel “grammatical multitasking” paradigm: the participants had to read (i.e., decode) and to paraphrase (encode) sentences presented in fragments, responding to each input fragment as fast as possible with a fragment of the paraphrase. The main finding was that grammatical constraints with respect to upcoming input that emanate from decoded sentence fragments are immediately replaced by grammatical expectations emanating from the structure of the corresponding paraphrase fragments. This evidences that the two modalities have direct access to, and operate upon, the same (i.e., token-identical) grammatical structures. This is possible only if the grammatical encoding and decoding processes command the same, shared grammatical workspace. Theoretical implications for important forms of grammatical multitasking—self-monitoring, turn-taking in dialogue, speech shadowing, and simultaneous translation—are explored

Speech Planning at Turn Transitions in Dialog Is Associated With Increased Processing Load

“…According to the simplest systematics of turn taking (Sacks, Scheglo, & Jefferson, 1974), the first participant who speaks up when a turn transition becomes relevant gains the right to take the next turn. While language production and comprehension are assumed to engage-at least partly-the same cognitive resources (Hagoort & Indefrey, 2014;Kempen, Olsthoorn, & Sprenger, 2012;Menenti, Gierhan, Segaert, & Hagoort, 2011;Silbert, Honey, Simony, Poeppel, & Hasson, 2014) potentially increased processing load due to parallel processing of the two might be traded for the benefit of early planning, leading to shorter turn-transition times (Barthel et al, 2016(Barthel et al, , 2017. The alternative account questions the assumption that the simultaneity of comprehension and production in conversation drastically increases processing load.…”

The Timing of Utterance Planning in Task-Oriented Dialogue: Evidence from a Novel List-Completion Paradigm

“…Hence, the model accounts for short gaps between turns by assuming that content planning starts as early as possible, comprehension continues in parallel with response preparation, and articulation can be launched from a prepared formulation when transition becomes relevant. Such parallel processing should be cognitively demanding, since speaking and listening can interfere with one another and are known to take up processing resources (Schriefers et al, 1990; Kemper et al, 2003; Kubose et al, 2006; Boiteau et al, 2014; Sjerps and Meyer, 2015) and are partly supported by the same neurological system (Hagoort et al, 1999; Menenti et al, 2011; Kempen et al, 2012; Segaert et al, 2012). Thus, speakers face the task of producing a response under time pressure while keeping capacity demands and interference between comprehension and production within reasonable bounds.…”

On the parity of structural persistence in language production and comprehension

“…The information must be similar or communication would founder, but how the information is used could be the same or different in the two modalities. A strong hypothesis is that speakers and listeners know similar things and use their knowledge in similar ways (Bresnan & Kaplan, 1984; Kempen, Olsthoorn, & Sprenger, 2012; Pickering & Garrod, 2013; Sag & Wasow, 2011). Yet it is undeniable that listeners can understand words and sentences that they do not and perhaps cannot produce (Clark & Malt, 1984), that comprehension and production begin and end with different information, and that the peripheral sensory and motor apparatus for sensation and action are necessarily distinct.…”

“…In neuropsychological impairments, deficits in general cognitive resources might obscure underlying uniformity (Caplan, 1996; Caplan & Waters, 1995; Caplan, Waters, DeDe, Michaud, & Reddy, 2007). Apparent differences in difficulty could stem from people’s typical failure to create as much representational detail after listening as before speaking, even though such detail is achievable (Bock, Dell, Garnsey, Kramer, & Kubose, 2007; Kempen et al, 2012). …”