Phonological neighbors cooperate during spoken-sentence processing: Evidence from a nonword detection task.

We used a novel nonword detection task to examine the lexical competition principle postulated in most models of spoken word recognition. To do so, in Experiment 1 we presented sequences of spoken words with half of the sequences containing a nonword, and the target nonword (i.e., press a response key whenever you detect a nonword in the sequence) could either be phonologically related (a phonological neighbor) or unrelated to the immediately preceding word. We reasoned that the reactivation of a phonological neighbor during target nonword processing should delay the moment at which a nonword decision can be made. Contrary to our hypothesis, participants were faster at detecting nonwords when they were preceded by a phonological neighbor compared with an unrelated word. In Experiment 2, an inhibitory effect of phonological relatedness on nonword decisions was observed in a classic priming situation using the same set of related and unrelated word-nonword pairs. We discuss the implications of these findings in regard to the main models of spoken word recognition, and conclude that our specific experimental set-up with phonological neighbors embedded in spoken sentences is more sensitive to cooperative interactions between co-activated sublexical representations than lexical competition between co-activated lexical representations, with the latter being modulated by whether or not the words compete for the same slot in time.

Sentence superiority in the reading brain.

When a sequence of written words is briefly presented and participants are asked to identify just one word at a post-cued location, then word identification accuracy is higher when the word is presented in a grammatically correct sequence compared with an ungrammatical sequence. This sentence superiority effect has been reported in several behavioral studies and two EEG investigations. Taken together, the results of these studies support the hypothesis that the sentence superiority effect is primarily driven by rapid access to a sentence-level representation via partial word identification processes that operate in parallel over several words. Here we used MEG to examine the neural structures involved in this early stage of written sentence processing, and to further specify the timing of the different processes involved. Source activities over time showed grammatical vs. ungrammatical differences first in the left inferior frontal gyrus (IFG: 321-406 ms), then the left anterior temporal lobe (ATL: 466-531 ms), and finally in both left IFG (549-602 ms) and left posterior superior temporal gyrus (pSTG: 553-622 ms). We interpret the early IFG activity as reflecting the rapid bottom-up activation of sentence-level representations, including syntax, enabled by partly parallel word processing. Subsequent activity in ATL and pSTG is thought to reflect the constraints imposed by such sentence-level representations on on-going word-based semantic activation (ATL), and the subsequent development of a more detailed sentence-level representation (pSTG). These results provide further support for a cascaded interactive-activation account of sentence reading.

On the distinction between position and order information when processing strings of characters.

To probe the processing of gaze-dependent positional information and gaze-independent order information when matching strings of characters, we compared effects of visual similarity (hypothesized to affect gaze-centered position coding) with the effects of character transpositions (hypothesized to affect the processing of gaze-independent order information). In Experiment 1, we obtained empirical measures of visual similarity for pairs of characters, separately for uppercase consonants and keyboard symbols. These similarity values were then used in Experiment 2 to create pairs of four-character stimuli (four letters or four symbols) that could differ by substituting one character with a different character from the same category that was visually similar (e.g., FJDK-FJBK) or dissimilar (e.g., FJVK-FJBK). We also compared the effects of transposing two characters (e.g., FBJK-FJBK) with substituting two characters (e.g., FHSK-FJBK). "Different" responses were harder to make in the single substitution condition when the substituted character was visually similar, and this effect was not conditioned by character type. On the other hand, transposition costs (i.e., greater difficulty in detecting a difference with transpositions compared with double substitutions) were greater for letters compared with symbols. We conclude that visual similarity mainly affects the generic gaze-dependent processing of complex visual features, and that the encoding of letter order involves a mechanism that is specific to reading.

Effects of vertically aligned flankers during sentence reading.

We examine whether information lying above and below a line of text being read can impact on reading fluency. We did so by placing length-matched flankers above and below each word in a sequence of words. We found that identical flankers facilitated sentence reading, compared with syntactically correct different text flankers, in both reading-for-meaning (Experiment 1) and grammatical decisions (Experiment 2). Experiment 3 replicated the same text facilitation in grammatical decisions and found no significant difference between different word and nonword distractors. Experiment 4 tested for an impact of case matching across targets and flankers and found a significantly greater same text facilitation when targets and flankers were in the same case. These results suggest that the same text facilitation effect might well be driven by crowding mechanisms that are more sensitive to vertically aligned information when reading horizontally aligned text. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Phonological decoding and morpho-orthographic decomposition: Complementary routes during learning to read.

We examined the reliance on phonological decoding and morpho-orthographic decomposition strategies in developing and skilled readers of French. A lexical decision experiment was conducted where the critical stimuli were four types of nonwords, all derived from the same base word, such as the French word visage (face) in the following examples: (a) pseudo-homophone (PsH) nonwords (e.g., visaje), (b) orthographic controls for PsH nonwords (e.g., visape), (c) pseudo-morphemic (PsM) nonwords (e.g., visageable), and (d) orthographic controls for PsM nonwords (e.g., visagealle, where alle is not a suffix in French). Responses to PsH and PsM nonwords and their controls were studied in three groups of school children (Grades 1, 2, and 5) and one group of skilled adult readers. PsH interference effects (i.e., more errors to PsH nonwords than to the corresponding controls) decreased during reading acquisition to become nonsignificant in skilled readers. Interestingly, the opposite pattern was seen in PsM interference effects (also measured in terms of accuracy), which were already significant in Grade 1 and increased during reading development to reach their maximum in skilled readers. These results point toward opposing learning trajectories in the use of phonological and morphological information when learning to silently read for meaning.

The dynamics of multiword sequence extraction.

Being able to process multiword sequences is central for both language comprehension and production. Numerous studies support this claim, but less is known about the way multiword sequences are acquired, and more specifically how associations between their constituents are established over time. Here we adapted the Hebb naming task into a Hebb lexical decision task to study the dynamics of multiword sequence extraction. Participants had to read letter strings presented on a computer screen and were required to classify them as words or pseudowords. Unknown to the participants, a triplet of words or pseudowords systematically appeared in the same order and random words or pseudowords were inserted between two repetitions of the triplet. We found that response times (RTs) for the unpredictable first position in the triplet decreased over repetitions (i.e., indicating the presence of a repetition effect) but more slowly and with a different dynamic compared with items appearing at the predictable second and third positions in the repeated triplet (i.e., showing a slightly different predictability effect). Implicit and explicit learning also varied as a function of the nature of the triplet (i.e., unrelated words, pseudowords, semantically related words, or idioms). Overall, these results provide new empirical evidence about the dynamics of multiword sequence extraction, and more generally about the role of statistical learning in language acquisition.

Lexical competition in the flankers task revisited.

We investigated the impact of flanking stimuli that are orthographic neighbors of central target words in the reading version of the flankers task. Experiment 1 provided a replication of the finding that flanking words that are orthographic neighbors of central target words (e.g., BLUE BLUR BLUE) facilitate lexical decisions relative to unrelated word flankers (e.g., STEP BLUR STEP). Experiment 2 tested the hypothesis that this facilitatory effect might be due to the task that was used in Experiment 1 and in prior research-the lexical decision task. In Experiment 2 the task was perceptual identification, and here we observed that orthographic neighbor flankers interfered with target word identification. Experiment 2 also included a bigram flanker condition (e.g., BL BLUR UE), and here the related bigram flankers facilitated target word identification. We conclude that when the task requires identification of a specific word, effects of lexical competition emerge over and above the facilitatory effects driven by the sublexical spatial pooling of orthographic information across target and flankers, and that the inhibitory influence of lexical competition has an even stronger impact when flankers are whole words.

Constraints on integration of orthographic information across multiple stimuli: effects of contiguity, eccentricity, and attentional span.

Five flanked lexical decision experiments investigated the integration of information across spatially distinct letter strings. Experiment 1 found no significant difference between quadrigram flankers (e.g., CKRO ROCK CKRO) and double bigram flankers (e.g., CK RO ROCK CK RO). Experiment 2 varied the eccentricity of single bigram flankers and found that closer flankers generated greater effects. A combined analysis of these experiments revealed that the double bigram condition (Experiment 1) was less effective than the close single bigram condition (Experiment 2). Experiment 3 tested one explanation for this pattern - that the outer bigrams in the double bigram condition interfered with processing the inner bigrams, and that spatial integration only operates across adjacent stimuli. In Experiment 3, outer bigrams were now a repeat of the inner bigram (e.g., RO RO ROCK CK CK), and this repeated bigram condition was still found to be significantly less effective than single bigrams. Experiments 4 and 5 tested an alternative explanation whereby the addition of spatially distinct flanking stimuli increases the spread of spatial attention, hence reducing the impact of proximal flankers. In line with this explanation, we found no significant difference between repeated bigram flankers and a condition where only the inner bigram was related to the target (e.g., CA RO ROCK CK SH). We conclude that spatial integration processes only operate across the central target and proximal flankers, and that these effects are diluted by the increased spread of spatial attention caused by additional spatially distinct flankers.

When phonological neighbours cooperate during spoken sentence processing.

This study examined for the first time the impact of the presence of a phonological neighbour on word recognition when the target word and its neighbour co-occur in a spoken sentence. To do so, we developed a new task, the verb detection task, in which participants were instructed to respond as soon as they detected a verb in a sequence of words, thus allowing us to probe spoken word recognition processes in real time. We found that participants were faster at detecting a verb when it was phonologically related to the preceding noun than when it was phonologically unrelated. This effect was found with both correct sentences (Experiment 1) and with ungrammatical sequences of words (Experiment 2). The effect was also found in Experiment 3 where adjacent phonologically related words were included in the non-verb condition (i.e., word sequences not containing a verb), thus ruling out any strategic influences. These results suggest that activation persists across different words during spoken sentence processing such that processing of a word at position n + 1 benefits from the sublexical phonology activated during processing of the word at position n. We discuss how different models of spoken word recognition might be able (or not) to account for these findings.

The impact of atypical text presentation on transposed-word effects.

When asked to decide if an ungrammatical sequence of words is grammatically correct or not, readers find it more difficult to do so (longer response times (RTs) and more errors) if the ungrammatical sequence is created by transposing two words from a correct sentence (e.g., the white was cat big) compared with matched ungrammatical sequences where transposing two words does not produce a correct sentence (e.g., the white was cat slowly). Here, we provide a further exploration of transposed-word effects when reading unspaced text in Experiment 1, and when reading from right-to-left ("backwards" reading) in Experiment 2. We found significant transposed-word effects in error rates but not in RTs, a pattern previously found in studies using a one-word-at-a-time sequential presentation. We conclude that the absence of transposed-word effects in RTs in the present study and prior work is due to that atypical nature of the way that text was presented. Under the hypothesis that transposed-word effects at least partly reflect a certain amount of parallel word processing during reading, we further suggest that the ability to process words in parallel would require years of exposure to text in its regular format.

Simple questions on simple associations: regularity extraction in non-human primates.

When human and non-human animals learn sequences, they manage to implicitly extract statistical regularities through associative learning mechanisms. In two experiments conducted with a non-human primate species (Guinea baboons, Papio papio), we addressed simple questions on the learning of simple AB associations appearing in longer noisy sequences. Using a serial reaction time task, we manipulated the position of AB within the sequence, such that it could be either fixed (by appearing always at the beginning, middle, or end of a four-element sequence; Experiment 1) or variable (Experiment 2). We also tested the effect of sequence length in Experiment 2 by comparing the performance on AB when it was presented at a variable position within a sequence of four or five elements. The slope of RTs from A to B was taken for each condition as a measurement of learning rate. While all conditions differed significantly from a no-regularity baseline, we found strong evidence that the learning rate did not differ between the conditions. These results indicate that regularity extraction is not impacted by the position of the regularity within a sequence and by the length of the sequence. These data provide novel general empirical constraints for modeling associative mechanisms in sequence learning.

Readers use word length information to determine word order.

It is assumed by the OB1-reader model that activated words are flexibly associated with spatial locations. Supporting this notion, recent studies show that readers can confuse the order of words. As word position coding is assumed to rely, among other things, on low-level visual cues, OB1 predicts that it must be harder to determine the order of words when these are of equal length, and consequently, that it is more difficult to read uniform word length sentences. Here we review recent evidence, obtained by our peers, in line with this prediction. We additionally report an analysis of eye-movement data from the GECO corpus, replicating the phenomenon in a natural reading setting, and an experiment revealing a negative impact of length uniformity in a grammatical decision task. By virtue of the spatiotopic sentence-level representation, OB1-reader is currently the only model of reading to account for these behaviors. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Parallel word reading revealed by fixation-related brain potentials.

During reading, the brain is confronted with many relevant objects at once. But does lexical processing occur for multiple words simultaneously? Cognitive science has yet to answer this prominent question. Recently it has been argued that the issue warrants supplementing the field's traditional toolbox (response times, eye-tracking) with neuroscientific techniques (EEG, fMRI). Indeed, according to the OB1-reader model, upcoming words need not impact oculomotor behavior per se, but parallel processing of these words must nonetheless be reflected in neural activity. Here we combined eye-tracking with EEG, time-locking the neural window of interest to the fixation on target words in sentence reading. During these fixations, we manipulated the identity of the subsequent word so that it posed either a syntactically legal or illegal continuation of the sentence. In line with previous research, oculomotor measures were unaffected. Yet, syntax impacted brain potentials as early as 100 ms after the target fixation onset. Given the EEG literature on syntax processing, the presently observed timings suggest parallel word reading. We reckon that parallel word processing typifies reading, and that OB1-reader offers a good platform for theorizing about the reading brain.

Effects of alternating letter case on processing sequences of written words.

In three grammatical decision experiments, we examined the impact of alternating letter case on sentence reading to determine the locus of case-alternation effects. Experiments 1 and 2 compared grammatical decision responses ("Is this a grammatically correct sequence of words or not?") in three different conditions: (1) SAME CASE/same case; (2) alternating CASE between WORDS; and (3) aLterNaTing cAsE wItHin WoRdS. For the grammatically correct sequences, we observed significantly faster responses in the same-case conditions compared with the between-word case manipulation, as well as a significant advantage for the between-word condition compared with within-word alternating case. These results confirm that case-alternation deteriorates sentence reading, but more so at the level of single word processing (within-word alternation) than at the sentence level (between-word alternation). Experiment 3 demonstrated that between-word case-alternation facilitates sentence processing compared with an all-lowercase condition when betweenWORDspacesAREremoved. Therefore, in the absence of between-word spacing, case changes across words facilitate sentence processing, possibly by guiding readers' eyes to optimal locations for word identification.

On the role of interference in sequence learning in Guinea baboons (Papio papio).

It is well established that decay and interference are the two main causes of forgetting. In the present study, we specifically focus on the impact of interference on memory forgetting. To do so, we tested Guinea baboons (Papio papio) on a visuo-motor adaptation of the Serial Reaction Time task in which a target sequence is repeated, and a random sequence is interposed between repetitions, a similar situation as the one used in the Hebb repetition paradigm. In this task, one three-item sequence, the repeated sequence, was presented every second trial and interleaved with random sequences. Interference was implemented by using random sequences containing one item that was also part of the repeated sequence. In a first condition, the overlapping item was located at the same position as the repeated sequence. In a second condition, the overlapping item was located at one of the two other positions. In a third condition, there was no overlap between repeated and random sequences. Contrary to previous findings, our results reveal similar learning slopes across all three conditions, suggesting that interference did not affect sequence learning in the conditions tested. Findings are discussed in the light of previous research on sequence learning and current models of memory and statistical learning.

Multi-LEX: A database of multi-word frequencies for French and English.

Written word frequency is a key variable used in many psycholinguistic studies and is central in explaining visual word recognition. Indeed, methodological advances on single-word frequency estimates have helped to uncover novel language-related cognitive processes, fostering new ideas and studies. In an attempt to support and promote research on a related emerging topic, visual multi-word recognition, we extracted from the exhaustive Google Ngram datasets a selection of millions of multi-word sequences and computed their associated frequency estimate. Such sequences are presented with part-of-speech information for each individual word. An online behavioral investigation making use of the French 4-gram lexicon in a grammatical decision task was carried out. The results show an item-level frequency effect of word sequences. Moreover, the proposed datasets were found useful during the stimulus selection phase, allowing more precise control of the multi-word characteristics.

Effects of consonant-vowel status on transposed-phoneme priming.

Nonwords created by transposing two phonemes of auditory words (e.g., /buʒãle/) are more effective primes for the corresponding base word target (/bulãʒe/) than nonword primes created by substituting two phonemes (e.g., /buvãʀe/). In one in-lab experiment and one online experiment using the short-term phonological priming paradigm, here, we examine the role of vowels and consonants in driving transposed-phoneme priming effects. Results showed that facilitatory transposed-phoneme priming occurs when the transposed phonemes are consonants (/buʒãle/-/bulãʒe/; /lubãʒe/-/bulãʒe/), but not when they are vowels (/bãluʒe/-/bulãʒe/; /buleʒã/-/bulãʒe/). These results add to existing findings showing differences in the processing of vowels and consonants during spoken and visual word recognition. We suggest that differences in the speed of processing of consonants and vowels combined with differences in the amount of information provided by consonants and vowels relative to the identity of the word being recognized provide a complete account of the present findings.

Rime Priming Effects in Spoken Word Recognition.

In this study, we re-examined the facilitation that occurs when auditorily presented monosyllabic primes and targets share their final phonemes, and in particular the rime (e.g., /vɔʀd/-/kɔʀd/). More specifically, we asked whether this rime facilitation effect is also observed when the two last consonants of the rime are transposed (e.g., /vɔʀd/-/kɔʀd/). In comparison to a control condition in which the primes and the targets were unrelated (e.g., /pylt/-/kɔʀd/), we found significant priming effects in both the rime (/vɔdʀ/-/kɔʀd/) and the transposed-phoneme "rime" /vɔdʀ/-/kɔʀd/ conditions. We also observed a significantly greater priming effect in the former condition than in the latter condition. We use the theoretical framework of the TISK model (Hannagan et al., 2013) to propose a novel account of final overlap phonological priming in terms of activation of both position-independent phoneme representations and bi-phone representations.

Transposed-word effects in speeded grammatical decisions to sequences of spoken words.

We used the grammatical decision task (a speeded version of the grammaticality judgment task) with auditorily presented sequences of five words that could either form a grammatically correct sentence or an ungrammatical sequence. The critical ungrammatical sequences were either formed by transposing two adjacent words in a correct sentence (transposed-word sequences: e.g., "The black was dog big") or were matched ungrammatical sequences that could not be resolved into a correct sentence by transposing any two words (control sequences: e.g., "The black was dog slowly"). These were intermixed with an equal number of correct sentences for the purpose of the grammatical decision task. Transposed-word sequences were harder to reject as being ungrammatical (longer response times and more errors) relative to the ungrammatical control sequences, hence attesting for the first time that transposed-word effects can be observed in the spoken language version of the grammatical decision task. Given the relatively unambiguous nature of the speech input in terms of word order, we interpret these transposed-word effects as reflecting the constraints imposed by syntax when processing a sequence of spoken words in order to make a speeded grammatical decision.

Transposed-word effects when reading serially.

When asked to decide if an ungrammatical sequence of words is grammatically correct or not readers find it more difficult to do so (longer response times (RTs) and more errors) if the ungrammatical sequence is created by transposing two words from a correct sentence (e.g., the white was cat big) compared with a set of matched ungrammatical sequences for which transposing any two words could not produce a correct sentence (e.g., the white was cat slowly). Here, we provide a further exploration of transposed-word effects while imposing serial reading by using rapid serial visual presentation (RSVP) in Experiments 1 (respond at the end of the sequence) and 2 (respond as soon as possible-which could be during the sequence). Crucially, in Experiment 3 we compared performance under serial RSVP conditions with parallel presentation of the same stimuli for the same total duration and with the same group of participants. We found robust transposed-word effects in the RSVP conditions tested in all experiments, but only in error rates and not in RTs. This contrasts with the effects found in both errors and RTs in our prior work using parallel presentation, as well as the parallel presentation conditions tested in Experiment 3. We provide a tentative account of why, under conditions that impose a serial word-by-word reading strategy, transposed-word effects are only seen in error rates and not in RTs.