Research

Word learning and lexical competition between known and novel words

This project aims at investigating how novel words become able to engage in competition with other, already known words.

One way of describing this process is in terms of new connections being formed. For example, when one learns the new word nep new connections are formed between this novel word and other similar words (e.g. neck and net). As a result nep can now compete for activation with neck and net.

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Certain questions arise at this point, such as:

  1. What does it take for these new connections to form?
  2. How fast can these connections develop?
  3. Are these connections malleable?

By studying these issues we get closer to answering broader questions about the nature of lexical representations and how they are acquired. In addition, these findings may have important implications in regard to the way we design educational paradigms involving word learning. Lastly, our findings on the malleability of lexical compeition dynamics may shed light on the nature of atypical patterns of language processing that are linked to difficulties in suppressing competing representations.


Relevant report(s)

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Kapnoula, E.C., Packard, S., Gupta, P., & McMurray B. (2015). Immediate lexical integration of novel word forms. Cognition, 134, 85-99. pdf

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Kapnoula, E.C. & McMurray B. (2016). Newly learned word forms are abstract and integrated immediately after acquisition. Psychonomic Bulletin and Review. pdf

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Kapnoula, E.C. & McMurray B. (2016). Training alters the resolution of lexical interference: Evidence for plasticity of competition and inhibition. Journal of Experimental Psychology: General, 145(1), 8-30. pdf

Indexical effects on spoken word recognition

Is talker information part of lexical representations? Previous work has shown that information such as a talkerís gender, as well as and seemingly odder sources of information (e.g. a dog barking in the background) can affect spoken word recognition (Goldinger, 1998; McLennan & Luce, 2005; Pufahl & Samuel, 2014; Vitevitch & Donoso, 2011). However, such variability is thought to have no role in determining a wordís referent. This line of work asks whether the absence of indexical effects on referent selection is a result of learning or whether it is due to internal constraints of the system.

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Addressing this issue can allow us to reach a more comprehensive understanding of what lexical representations are and how they are formed.


Relevant report(s)

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Kapnoula, E.C. & Samuel A.G. (2017). Information about the talkerís voice can affect word meaning. Poster presented at the 20th ESCoP conference (ESCOP 2017), Potsdam, Germany.

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Kapnoula, E.C. & Samuel A.G. (2017). Talkerís voice can affect word meaning: Evidence from eye movements. Poster presented at the 58th Annual Meeting of the Psychonomic Society, Vancouver, British Columbia, Canada.

Individual differences in phoneme categorization

Listeners perceive speech sounds in a gradient way and this sensitivity to within-category differences is maintained all the way to the level of lexical activation. However, some listeners seem more gradient than others. Gradiency has traditionally been attributed to noise, and, thus, it is commonly considered an indicator of poor speech perception. However, gradiency may in fact indicate better perception of fine-grained differences, which may be beneficial for speech perception. This project aims at addressing the following questions:

  1. How can we quantify differences in gradiency in phoneme categorization?
  2. What makes some listeners more gradient than others?
  3. In what way does gradiency affect speech perception?

By examining the sources and consequences of gradiency in phoneme categorization, this work can inform our understanding of the fundamental mechanisms that support speech perception and spoken word recognition. Furthermore, by taking into account the role of individual differences, we can reach a better understanding of the variability observed within typical monolingual populations, but, in the long run, it may also help us better address the challenges that arise in the cases of multilingualism, as well various hearing and language-related disorders.


Relevant report(s)

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Kapnoula, E.C., McMurray, B., Kong, E., Winn M., & Edwards, J. (2014). Individual differences in phoneme categorization. Oral presentation at the 19th Mid-Continental Phonetics & Phonology Conference, Madison, WI, USA. pdf

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Kapnoula, E.C., Edwards, J., & McMurray, B. (2015). Gradient categorization of speech sounds helps listeners recover from lexical garden paths. Poster presented at the 14th Auditory Perception, Cognition, and Action Meeting, Chicago, IL, USA.

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Kapnoula, E.C., Winn M., Kong, E., Edwards, J. & McMurray, B. (2017). Evaluating the sources and functions of gradiency in phoneme categorization: An individual differences approach. Journal of Experimental Psychology: Human Perception and Performance, 43(9), 1594-1611.

Top-down effects on phoneme perception

The context in which a speech sound occurs affects the way we interpret it. For example, in a sentence like She went to Greece and laid all day on a sandy peach, one might hear the word peach as beach. However, there is a debate as to how early this happens; is low-level phoneme perception affected by the context (i.e. do we hear beach), or does this happen later in processing (i.e. do we decide the word was beach)? We investigate this by manipulating the preceding context (lexical, visual, or sentential) and measuring its effect on early auditory processing of speech sounds using event-related potentials.


Relevant report(s)

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Schreiber, K., Kapnoula E.C., & McMurray B. (2014). Lexical effects on early sensory processing reveals the role of top-down feedback in speech perception. Poster presented at the 19th Mid-Continental Phonetics & Phonology Conference, Madison, WI, USA.

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Sarrett, M.E., Kapnoula, E.C., & McMurray, B. (2017). Realtime integration of acoustic cues and semantic expectations in speech processing: Evidence from EEG. Poster to be presented at the 40th Annual Meeting of the Cognitive Science Society, Madison, WI, USA.

Visual word recognition

Once we learn how to read words the process seems to unfold automatically. Despite the ease in which we perform a word reading task we still haven't come to an agreement as the underlying processes. Some of the main questions are:

  1. How does this happen? What is an accurate, mechanistic description of this process?
  2. How can we evaluate and compare between different accounts?
  3. What kind of differences are there between languages in the way readers process visual input?

In addition to our interest on the specific questions, visual word recognition also provides an arena on which fundamental issues of cognitive science are tested (e.g. serial vs parallel activation, localist versus distributed representations, learned versus hardwired information).


Relevant report(s)

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Protopapas, A. & Kapnoula, E.C. (2013). Exploring word recognition with selected stimuli: The case for decorrelated parameters. Poster presented at the 35th Annual Cognitive Science Conference, Berlin, Germany. pdf

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Protopapas, A. & Kapnoula, E.C. (2016). Short-term and long-term effects on visual word recognition. Journal of Experimental Psychology: Learning, Memory, and Cognition. pdf

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Protopapas, A., Orfanidou, E., Taylor, J., Karavasilis, E., Kapnoula, E.C., Panagiotaropoulou G., Velonakis, G., Poulou, L.S, Smyrnis, N., & Kelekis, D. (2016). Evaluating cognitive models of visual word recognition using fMRI: Effects of lexical and sublexical variables, NeuroImage. pdf

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Kapnoula, E.C. & Protopapas, A. (2017). Lexical and sublexical effects on visual word recognition in Greek: Comparing human behavior to the Dual Route Cascaded (DRC) model, Language, Cognition and Neuroscience, 32(10), 1290-1304.