Form Priming Research Articles

Does English coronal place assimilation create lexical ambiguity?

The purpose of this study was to determine how potential lexical ambiguity produced by place assimilation is resolved. Four cross-modal form priming experiments using primes in sentential contexts were performed. In the first 2, prime items had underlyingly coronal offsets (e.g., right) with assimilated noncoronal place. The primes were judged to be perceptually ambiguous (between right and ripe) in Experiment 1 and noncoronal (ripe) in Experiment 2 in off-line testing. In Experiment 3, primes were replaced with corresponding underlyingly noncoronal items (ripe). In all 3 experiments, participants showed selective priming for the underlying form of the prime. A 4th form priming experiment using the gated tokens of priming stimuli used in Experiment 2 examined the role of postlexical context on this process. In this experiment, participants showed priming for both underlying and surface forms of the prime.

Variation and assimilation in German: Consequences for lexical access and representation

The consequences of surface variation in speech on lexical access have recently received considerable attention. The lexical system is intolerant to mismatch between input and lexical representation, but an exception is phonologically regular variation. One example is assimilation of consonants that adopt the place of articulation of adjacent consonants in fast speech. Data are presented from crossmodal form priming experiments in German on regressive and progressive assimilation at word boundaries. The results show that some, but not all forms of lawful variation are tolerated by the lexical system. The consequences of these findings for psycholinguistic and linguistic models, some of which incorporate explanations for regular variation, are discussed.

Assimilation and Anticipation in Continuous Spoken Word Recognition

English coronal place assimilation is one of many productive phonological processes that change the phonological form of words. It may, for example, cause speakers to pronounce green as something approximating [grin] or [grim] in different contexts. The present work examines how listeners recognize words that have undergone this modification. Current accounts are broadly differentiated by two issues: (1) whether listeners generally recognize words that have undergone word-final, single-feature modification, and (2) how context effects in the perception of assimilated speech are interpreted. Experiment 1 employs form priming to demonstrate that listeners tolerate single-feature mismatch resulting from both phonologically plausible and phonologically implausible word form modification when recognizing words heard in context. Experiments 2 and 3 employ phoneme monitoring and negative rhyme priming paradigms, respectively, to demonstrate that listeners use assimilation to anticipate upcoming context. Evidence for anticipation is contrasted with claims that listeners use context to regressively infer the underlying form of place-assimilated segments.

Repetition and form priming interact with neighborhood density at a brief stimulus onset asynchrony

The relationships between repetition- and form-priming effects and neighborhood density were analyzed in two masked priming experiments with the lexical decision task. Given that form-priming effects appear to be influenced by a word's orthographic neighborhood, it is theoretically important to find out whether repetition priming also differs as a function of the word's orthographic neighborhood. Within an activation framework, repetition- and form-priming effects are just quantitatively different phenomena, whereas the two effects are qualitatively different in a serial-ordered model of lexical access (the entry-opening model). The results show that repetition- and form-priming effects were stronger for hermit words than for words with many neighbors. These results pose some problems for both activation and serial-ordered models. The implications of these results for determining how neighbors affect the identification of a word are discussed.

Masked priming for prefixed words with bound stems: Does submit prime permit?

Masked priming effects for prefixed words sharing a bound stem (e.g., submit-PERMIT) are compared with priming effects for semantically transparent prefixed words (e.g., fold-UNFOLD). In three experiments, priming effects were obtained for both types with no significant difference between them. These results suggest that semantic transparency is not critical for priming in this paradigm. However, in Experiment 2, priming in the bound stem condition did not differ significantly from an orthographic control condition (e.g., shallow-FOLLOW). In Experiment 3, form priming effects were suppressed by the use of close distractors and a longer prime duration. The morphological effects remained unaltered, indicating that they were not a product of orthographic overlap. The magnitude of bound stem priming was also found to be related to productivity of the stem.

Exposure to print and word recognition processes.

The effect of exposure to print on the efficiency of phonological and orthographic word recognition processes was examined by comparing two groups of university students having similar reading comprehension scores but different levels of exposure to print. Participants with a high level of exposure to print were faster and more accurate in naming pseudowords, in choosing the correct member of a homophone pair, and in making lexical decisions when nonwords were pseudohomophones. In the lexical decision task, low-print-exposure participants were more sensitive to the frequency of the orthographic patterns in the stimuli. The results of a form priming task demonstrated that high-print-exposure participants more quickly and strongly activated the orthographic representations of common words and subsequently more strongly activated the corresponding phonological representations. Even among successful students, differences in exposure to print produce large differences in the efficiency of both orthographic and phonological word recognition processes.

Neighbourhood Effects on Masked Form Priming in Developing Readers

The processing of a written word can be facilitated by the brief prior presentation of an orthographically similar stimulus. However, for adults, this masked form-priming effect does not occur if the target looks like many other words (i.e. if it has many neighbours). The usual interpretation of this result is that the adult word recognition system is tuned to the differing discrimination demands of words: If a word looks like many others, a more precise recognition procedure is required than if it is orthographically distinctive. This theory has developmental implications: Children should show more form priming for high neighbourhood words than adults and should show a gradual reduction in priming as their written vocabularies become larger. Masked form priming was examined in three groups of developing readers, from grades 2, 4 and 6, and a group of adults. In a lexical decision task, the children showed significantly greater priming overall than the adults for high N words. However, the predicted gradual attenuation across age was not found. Supplementary analyses suggested that the adaptation to lexical density may not occur until a somewhat more advanced stage of reading than we had first expected.

Competitive processes during word-form encoding

Abstract: A highly constrained model of phonological encoding, which is minimally affected by the activation levels of alternative morphemes and phonemes, is proposed. In particular, weaver11predicts only facilitatory effects on word production of the prior activation of form related words. However, inhibitory effects of form priming that suggest that a more strongly competitive system is required exist in the literature. Despite superficial similarities, the approach taken by Levelt, Roelofs & Meyer to the problem of word-form encoding differs fundamentally from previous attempts to model this process. This difference hinges on the attitude taken to noise in the system. The encoding of most words occurs within a sea of activated alternative morphemes and their constituent sublexical representations. Some of this activation comes from external sources such as the speech of others or written language. Some activation will be generated directly by the utterance to be produced (i.e., the residual activation of the morphemes just articulated and the anticipatory activation of those to be generated). There is also activation of words that do not form part of the intended utterance but are related in form to a word to be produced (e.g., malapropisms: saying “apartment” when you intended to say “appointment”). Traditionally, models of word-form encoding have used this riot of background activation to explain how speech errors can occur by incorporating selection mechanisms that are sensitive to the activation levels of alternative representations. In Dell’s (1986) model, the selection of a given phoneme is determined by its level of activation during an ordinal selection process. Alternatively, inhibitory or competitive mechanisms have been proposed. Stemberger (1985) postulates inhibition between form-related lexical representations activated by feedback from shared phonemes. Sevald and Dell (1994) propose competition between activated phonemes during a left-to-right assignment process of segments to frames. In contrast, Levelt et al. postulate no competitive selection process at the morpheme level and no feedback of activation from phonemes to morphemes. In addition, the selection by checking device employed in weaver11 divorces the selection and encoding of phonemes from their level of activation, thereby ensuring that encoding runs correctly regardless of the activation levels of alternative phonemes. weaver11 restricts competition to phonetic encoding processes but even here the activation of form related morphemes will speed encoding of the target by increasing the numerator of the access ratio for the target syllables compared with unrelated syllable programs. The strict limitations on activation spreading and competition

Phonological Priming by Masked Nonword Primes in the Lexical Decision Task

The pseudohomophone test is whether the processing of a word target can be facilitated by a masked homophonic nonword prime independent of the visual similarity between them. The significance of the test is in respect to the hypothesized contributions of phonological and orthographic codes within dual-route theories. Using the mask–prime–target presentation sequence and prime durations typical of form priming experiments (e.g., 57 ms), we found that pseudohomophone primes (e.g., KLIP) reduced lexical decision times to targets in dense neighborhoods (e.g.,clip) relative to visually similar control primes (e.g., PLIP). We also found superior pseudohomophonic priming at a prime duration (29 ms) previously considered too brief for the emergence of phonological codes. The basis for these successful pseudohomophone tests in English was overall phonological similarity of prime and target rather than common onsets, rimes, or number of overlapping letters. Discussion focused on the need for models of visual word recognition in which phonology assumes the leading role.

Effects of vowel deletion on lexical access

Vowel elision is a common phonological process whereby an unstressed /ə/ (schwa) vowel is deleted during pronunciation. In three syllable words, the deleted /ə/ occurs in the medial posttonic position (different /dIfr schwant/ → [dIfr schwant]). In two syllable words, the deleted /ə/ occurs in the first syllable (police /polis/ → [plis]). These elided versions (reduced form) are commonly accepted as alternatives to canonical (full form) pronunciations. Two auditory form priming experiments used vowel elision to investigate the effects of phonological variability on lexical access. Subjects were asked to make a lexical decision to either the full (canonical) or reduced (elided) version of a target word after being primed by either the full or reduced form of the same word or an unrelated control. For both experiments, the results showed that the reduced version was a less effective prime than the full version. Accuracy rates indicated that the two syllable reduced versions were less acceptable variants. The results suggest an asymmetry in the effects of vowel elision in speech recognition and are discussed in terms of similarity mapping and representation of lexical form.

Masked form priming in writing words from pictures: Evidence for direct retrieval of orthographic codes

Three experiments used the masked priming paradigm to investigate the role of orthographic and phonological information in written picture naming. In all the experiments, participants had to write the names of pictures as quickly as possible under three different priming conditions. Nonword primes could be: (1) phonologically and orthographically related to the picture name; (2) orthographically related as in (1) but phonologically related to a lesser degree than in (1); (3) orthographically and phonologically unrelated except for the first consonant (or consonant cluster). Orthographic priming effects were observed with a prime exposure duration of 34 ms (Experiments 1 and 2) and of 51 ms (Experiment 3). In none of the experiments, did homophony between primes and picture names yield an additional advantage. Taken together, these findings support the view of the direct retrieval of orthographic information through lexical access in written picture naming, and thus argue against the traditional view that the retrieval of orthographic codes is obligatorily mediated by phonology.

Masked Orthographic Priming: The Effect of Prime-Target Legibility

The occurrence of extensive orthographic form-priming may provide reasons for preferring connectionist-type models over table-lookup (algorithmic) ones. Short-term masked priming procedures, using either tachistoscopic identification or lexical decision as the response measure, have shown consistent form-priming effects. Unfortunately, different results emerge depending on the procedure used. With the identification procedure, almost any orthographic overlap between prime and target is sufficient for priming to occur, but with the lexical decision procedure, form priming effects are much more limited in scope. The experiments reported here show that accuracy in the masked identification paradigm is influenced by the legibility of the target stimulus when superimposed on an image of the prime, even though there is no orthographic overlap between the two stimuli. Yet for the lexical decision version of the masked priming procedure there is no difference in latency or error rate as a function of legibility. It is further shown that the presence or absence of the legibility effect has little to do with the nature of the task required of the subject, but is instead a function of the duration of the target–-i.e. the legibility effect depends on having the prime and the target both displayed rapidly, and both masked. Failing to take legibility effects into account may lead to problems in interpreting the exact extent of form-priming effects in studies that use the identification procedure.

A study of masked form priming in picture and word naming.

We report a series of picture- and word-naming experiments in which the masked priming paradigm with prime exposures brief enough to prevent prime identification were used. Experiment 1 demonstrates that the prior presentation of the same word prime facilitates both picture and word naming independently of target frequency. In Experiments 2 and 3, primes that were pseudohomophones of picture targets produced facilitatory effects compared with orthographic controls, but these orthographically similar nonword primes did not facilitate picture naming compared with unrelated controls. On the other hand, word targets were primarily facilitated by orthographic prime-target overlap. This marked dissociation in the priming effects obtained with picture and word targets is discussed in relation to different explanations of masked form priming effects in visual word recognition and current models of picture and word naming.

Effects of Orthography are Independent of Phonology in Masked form Priming

Briefly presented forward-masked primes that share letters with a word target have been shown to facilitate performance in different word recognition tasks. However, in all the experiments that have previously reported these facilitatory effects, related primes not only shared more letters with the target than did unrelated primes (orthographic priming), but they also shared more phonemes (phonological priming). The stimuli used in the present experiments allow us to separate out the effects of orthographic priming from phonological priming. Varying prime exposure duration from 14 to 57 msec, it is shown that effects of orthography follow a distinct time-course from the effects of phonology, and that orthographic facilitation does not result from a confound with phonological prime-target overlap.

Inhibitory effects in form priming: Evaluating a phonological competition explanation.

Inhibitory effects in form priming: Evaluating a phonological competition explanation.

Inhibitory effects in form priming: Evaluating a phonological competition explanation.

Although a majority of studies support the notion that formally similar primes facilitate target processing, recent research has shown inhibition effects in some circumstances, particularly with high-frequency targets. The present studies focused on an explanation of this effect provided by a recent phonological competition model. Lexical decision results using rhyming primes indicate that the inhibition is more prevalent at short stimulus onset asynchronies and is unaffected by requiring verbal report of the prime. Naming results indicate that the inhibition only arises with irregular word pairs. Neither this model nor any of the models considered provided an adequate explanation of these effects. An alternative model that incorporates automatic, lexically based inhibition and strategically based facilitation processes is proposed. A basic assumption of most models of word recognition is that when a word is identified, a change is produced in the activation levels of the lexical processing structures of formally similar words (Humphreys, Evert, & Quinlan, 1990; McClelland & Rumelhart, 1981; Morton, 1979; Paap, McDonald, Schvaneveldt, & Noel, 1987; Paap, Newsome, McDonald, & Schvaneveldt, 1982; Seidenberg & McClelland, 1989). Yet, finding evidence for this change of activation has been somewhat difficult. For example, using a lexical decision task, Meyer, Schvaneveldt, and Ruddy (1974) reported only a small and nonsignificant facilitation from rhyming primes (i.e., primes that were both orthographically and phonologically similar to their targets). Although subsequent work (Hanson & Fowler, 1987; Hillinger, 1980; Lupker & Williams, 1989; Shulman, Hornak, & Sanders, 1978) has seemed to confirm Meyer et al.'s facilitation effect, failures to observe any effect of rhyming primes have also appeared in the literature (e.g., Martin & Jensen, 1988). Until recently, however, the general consensus has been that the bulk of the data support this basic assumption.

Bodies, antibodies, and neighborhood-density effects in masked form priming.

Facilitatory priming effects due to similarity of orthographic form are obtained for high-N target words provided that they have low-frequency bodies and the body is shared between the prime and target (e.g., perd-HERD). Conversely, it is shown that low-N target words show priming regardless of the frequency of the body, provided that the prime and target do not share the same body (e.g., drice-DRIVE). If the body is shared, then priming occurs only for targets with low-frequency bodies. These results suggest that neighborhood density should be defined in terms of both individual letter units and subsyllabic units and that both types of density jointly determine priming.

Bodies, antibodies, and neighborhood-density effects in masked form priming.

Bodies, antibodies, and neighborhood-density effects in masked form priming.

Automatic letter priming in an alphabetic decision task

An alphabetic decision task was used to study effects of form priming on letter recognition at very short prime durations (20 to 80 msec). The task required subjects to decide whether a stimulus was a letter or a nonletter. Experiment 1 showed clear facilitatory effects of primes being either physically or nominally identical to the targets, with a stable advantage for the former. Experiment 2 demonstrated that uppercase letters are classified more rapidly as letters (vs. non-letters) when they are preceded by a briefly exposed, forward- and backward-masked, visually similar uppercase letter than when they are preceded by a visually dissimilar uppercase letter. Finally, Experiment 3 demonstrated that nominally identical and visually similar primes facilitate processing more than do nominally identical, visually dissimilar primes. The alphabetic decision task proved to produce sensitive and stable priming effects at the feature, letter, and response-choice level. The present results on letter-letter priming thus constitute a solid data base against which to evaluate other priming effects, such as word-letter priming. The results are discussed in light of current activation models of letter and word recognition and are compared with data simulated by the interactive activation model (McClelland & Rumelhart, 1981).