On the lexical representation(s) of compounds: A continuous picture naming study.

Abstract

The lexical representation of compound words in speech production is still under debate. While most studies with healthy adult speakers suggest that a single lemma representation is active during compound production, data from neuropsychological studies point toward multiple representations, with activation of the compound’s constituent lemmas in addition to the compound’s lemma. This study exploits the cumulative semantic interference effect to investigate the lexical representation of compounds in speech production. In a continuous picture naming experiment, category membership was established through the compounds’ first constituents (category animals: zebra crossing, pony tail, cat litter …), while the compounds themselves were not semantically related. Moreover, pictures depicting the compounds’ first constituents (zebra, pony, cat …) were presented as a control condition. As expected, naming latencies within categories increased linearly with each additionally named category member when producing monomorphemic words, which is interpreted as increasing interference during lexical selection. Importantly, this cumulative semantic interference effect was also observed for compounds. This indicates that the lemmas of the compounds’ first constituents were activated during compound production, causing interference due to their semantic relationship and thereby hampering the production of the whole compound. The results are thus in line with the multiple-lemma representation account (Marelli et al., 2012). We argue that the apparent contradiction between results of previous studies with healthy adult speakers and our current study can be explained by the different experimental paradigms used.

Cumulative semantic interference is blind to morphological complexity and originates at the conceptual level

“…More recently, the continuous picture naming paradigm with its robust cumulative semantic interference (CSI) effect has become increasingly popular [ 21 , 22 ]. It has been used to investigate lexical access in bilinguals [ 23 ], semantic integration of newly acquired words [ 24 ], lexical access in a social settings [ 25 , 26 ], the lexical representation of compounds [ 27 ] or whether or not lexical selection is a competitive process [e.g., 22 , 28 , 29 ]. Despite this multitude of studies using CSI as a tool to investigate different research questions, not all underlying processes of the effect itself are fully understood.…”

“…Participants’ naming latencies within each semantic category systematically increase in a linear fashion with each ordinal position, that is, as a function of previously named objects of the same category. This CSI effect is independent of the number of intervening unrelated items [ 22 , 28 , 30 – 32 ; but see 33 ] and survives multiple repetition cycles [ 27 , 28 , 34 ]. All existing models agree that the locus of cumulative interference, that is, the level at which it comes into effect and behavioural consequences arise, is the lexical level [ 3 , 9 , 22 , 28 – 30 ].…”

“…However, interference is assumed to come into effect at the lexical level, more specifically at the lemma level [e.g., 6 , but see 4 ], and recent empirical evidence suggests that compounds and simple nouns may not be represented in the same way at this level. While simple nouns (e.g., shelf ) are assumed to have a single entry at the lemma level [ 6 ], studies on compounds (e.g., bookshelf ) suggest that they may have multiple lemma representations [ 27 , 46 , 47 ], namely morpheme-sized lemma entries ( book and shelf) that complement the holistic compound lemma [for evidence from neuropsychological studies, see e.g., 46 , 48 , 49 ]. If compounds and simple nouns are differently represented on the level where cumulative interference is said to come into effect, different activation patterns might lead to different patterns of cumulative interference [for contrasting evidence, see e.g., 43 , 50 ].…”

“…While PWI studies report identical interference for compound distractor-target pairs (wooden spoon—bread knife; original materials in German) and simple noun distractor-target pairs [spoon—knife; 43 , Exp. 2], research suggests that effects in PWI are not necessarily transferable to the continuous paradigm [for recent discussions, see e.g., 3 , 27 ]. The only study that systematically manipulated morphological complexity in a continuous picture naming paradigm is our recently published study that investigated the representation of German compounds in speech production [ 27 ].…”

“…2], research suggests that effects in PWI are not necessarily transferable to the continuous paradigm [for recent discussions, see e.g., 3 , 27 ]. The only study that systematically manipulated morphological complexity in a continuous picture naming paradigm is our recently published study that investigated the representation of German compounds in speech production [ 27 ]. In this study, participants named pictures in a compound and a simple noun condition.…”