Can object identification difficulty be predicted based on disfluencies and eye-movements in connected speech?

Abstract

In the current study, we asked whether delays in the earliest stages of picture naming elicit disfluency. To address this question, we used a network task, where participants describe the route taken by a marker through visually presented networks of objects. Additionally, given that disfluencies are arguably multifactorial, we combined this task with eye tracking, to be able to disentangle disfluency related to word preparation from other factors (e.g., stalling strategy). We used visual blurring, which hinders visual identification of the items and thereby slows down selection of a lexical concept. We tested the effect of this manipulation on disfluency production and visual attention. Blurriness did not lead to more disfluency on average and viewing times decreased with blurred pictures. However, multivariate pattern analyses revealed that a classifier could predict above chance, from the pattern of disfluency, whether each participant was about to name blurred or control pictures. Impeding the conceptual generation of a message therefore affected the pattern of disfluencies of each participant individually, but this pattern was not consistent from one participant to another. Additionally, some of the disfluency and eye-movement variables correlated with individual cognitive differences, in particular with inhibition.

Semantic interference affects speech production by increasing disfluencies, not errors

“…A program written in PsychoPy [ 19 ] was used to create 12 networks, as in a previous studies [ 6 , 8 ]. Each network consisted of eight black-and-white drawings.…”

“…The point marker indicates a nine-step route through the network. In our previous experiments [ 6 , 8 ], the time it took the point marker to complete one network was 42 s, which was identified as the natural speech rate in Dutch. However, in the current study, we reduced the time to complete a network to 35 s in order to increase the effect of semantic interference [ 15 ].…”

“…For instance, some studies observed that delaying one of the earliest stages of picture naming (i.e. object recognition) resulted in increased numbers of prolongations [ 5 , but see 6 ]. Studies manipulating a subsequent stage of lexical access (i.e.…”

“…Therefore, the current study combined two paradigms, namely the network task and PWI task. To build the network task, we used the same methods and procedure as Pistono & Hartsuiker [ 6 , 8 ]. In addition, we tested the effect of semantic distractor words versus unrelated distractor words.…”

Deceptive deception: disfluencies are incorrectly interpreted as cues to deceptive speech

“…Indeed, speech disfluency measures are typically treated as dependent variables and tested one by one to determine whether they vary between experimental conditions when generalized across participants. In contrast, MVPA tests whether two experimental conditions can be distinguished based on all the information available to the classifier, such as different disfluency measures (Pistono & Hartsuiker, 2021, 2023.…”