Negative priming of unattended part primes: Implications for models of holistic and analytic processing in object recognition

The “hybrid” model of object recognition (Hummel, 2001) proposes that unattended objects are processed holistically, while attended objects are processed both holistically and analytically. Supporting evidence for this claim was reported by Thoma, Hummel, and Davidoff (2004) who showed that, unlike whole object primes, unattended split object parts (presumed to require analytic processing) do not elicit repetition priming. Here we tested the generality of this finding by contrasting priming for whole and part prime stimuli as a function of prime informativeness and by modifying the design so that both unattended whole and part prime displays contained a single perceptual object. Unlike Thoma et al. (2004) the results showed negative (rather than an absence of) priming for unattended half object primes. These findings place new constraints on theoretical models of the role of attention in object recognition.     

Are transposition effects specific to letters?

Recent research has consistently shown that pseudowords created by transposing two letters are perceptually similar to their corresponding base words (e.g., jugde–judge). In the framework of the overlap model (Gomez, Ratcliff, & Perea, 2008), this effect is due to a noisy process in the localization of the “objects” (e.g., letters, kana syllables). In the present study, we examine whether this effect is specific to letter strings or whether it also occurs with other “objects” (namely, digits, symbols, and pseudoletters). To that end, we conducted a series of five masked priming experiments using the same–different task. Results showed robust effects of transposition for all objects, except for pseudoletters. This is consistent with the view that locations of familiar objects (i.e., letters, numbers, and symbols) can be best understood as distributions along a dimension rather than as precise points.     

Selective impairment of masked priming in dual-task performance

This study investigated the impact of divided attention on masked priming. In a dual-task setting, two tasks had to be carried out in close temporal succession: a tone discrimination task and a masked priming task. The order of the tasks was varied between experiments, and attention was always allocated to the first task—that is, the first task was prioritized. The priming task was the second (nonprioritized) task in Experiment 1 and the first (prioritized) task in Experiment 2. In both experiments, “novel” prime stimuli associated with semantic processing were essentially ineffective. However, there was intact priming by another type of prime stimuli associated with response priming. Experiment 3 showed that all these prime stimuli can reveal significant priming effects during a task-switching paradigm in which both tasks were performed consecutively. We conclude that dual-task specific interference processes (e.g., the simultaneous coordination of multiple stimulus–response rules) selectively impair priming that is assumed to rely on semantic processing.     

The relationship between sentence meaning and word order: Evidence from structural priming in German

Most theories of human language production assume that generating a sentence involves several stages, including an initial stage where the prelinguistic message is determined and a subsequent stage of grammatical encoding. However, it is contentious whether grammatical encoding involves separate stages of grammatical-function assignment and linearization. To address this question, we examined the mapping between the message level and grammatical encoding in two structural priming experiments in which German speakers choose between three different structures expressing ditransitive events. Although speakers showed a tendency to repeat the order of constituents (noun phrase–prepositional phrase, NP–PP, vs. NP–NP), they were additionally primed to repeat the order of thematic roles when constituent structure was constant (NP_RECIPIENT–NP_THEME vs. NP_THEME–NP_RECIPIENT). Experiment 2 found that the latter effect could not be due to persistence of the order of phrases referring to animate and inanimate entities. These results suggest a direct mapping of thematic roles to word order, consistent with a model in which the message is mapped onto syntactic structure in a single stage.     

Inhibitory stroke neighbour priming in character recognition and reading in Chinese

In alphabetic languages, prior exposure to a target word's orthographic neighbour influences word recognition in masked priming experiments and the process of word identification that occurs during normal reading. We investigated whether similar neighbour priming effects are observed in Chinese in 4 masked priming experiments (employing a forward mask and 33-ms, 50-ms, and 67-ms prime durations) and in an experiment that measured eye movements while reading. In these experiments, the stroke neighbour of a Chinese character was defined as any character that differed by the addition, deletion, or substitution of one or two strokes. Prime characters were either stroke neighbours or stroke non-neighbours of the target character, and each prime character had either a higher or a lower frequency of occurrence in the language than its corresponding target character. Frequency effects were observed in all experiments, demonstrating that the manipulation of character frequency was successful. In addition, a robust inhibitory priming effect was observed in response times for target characters in the masked priming experiments and in eye fixation durations for target characters in the reading experiment. This stroke neighbour priming was not modulated by the relative frequency of the prime and target characters. The present findings therefore provide a novel demonstration that inhibitory neighbour priming shown previously for alphabetic languages is also observed for nonalphabetic languages, and that neighbour priming (based on stroke overlap) occurs at the level of the character in Chinese.     

Priming word order by thematic roles: No evidence for an additional involvement of phrase structure

Three experiments are reported that studied the priming of word order in German. Experiment 1 demonstrated priming of the order of case-marked verb arguments. However, order of noun phrases and order of thematic roles were confounded. In Experiment 2, we therefore aimed at disentangling the impact of these two possible factors. By using primes that differed from targets in phrase structure but were parallel with regard to the order of thematic roles, we nevertheless found priming demonstrating the critical impact of thematic roles. Experiment 3 replicated the priming effects from Experiments 1 and 2 within participants and revealed no evidence for a modulation of priming by phrase structure. Consequently, our findings suggest that word order priming crucially depends on the structural outline of thematic roles rather than on the linearization of phrases.     

Conceptual and perceptual factors in the picture superiority effect

This study tested the hypothesis that separate mechanisms mediate the planning of reaching and keypress responses. Participants performed a spatial precueing task with two preparation intervals (100 ms and 1000 ms) and three response sets: (a) pressing one of four response keys; (b) reaching with one of two hands; and (c) reaching with one hand. Reaction time results showed a pattern of precueing effects that strongly depended on the number of effectors in the response set and on the preparation interval. This outcome was interpreted as evidence that distinct mechanisms mediate the planning of multiple-effector and single-effector actions, with effector selection being relevant in the former but not in the latter. The theoretical implications of this conclusion are discussed.     

Effects of the degree of meaning similarity on cross-language semantic priming in highly proficient bilinguals

This study aimed to determine if access to meaning can be directly achieved from the words in the two languages, examining the influence of the degree of semantic overlap between related words across languages in the pattern of priming effects. Nonassociative semantically related words (members of the same category) were used, avoiding explicitly associative relationships. Using a priming paradigm, highly proficient Catalan–Spanish bilinguals were visually presented with pairs of words that either were translations of each other, had a very close semantic relationship (in terms of shared features), a close semantic relationship, or no semantic relationship at all. Participants performed either a lexical decision task (Experiment 1) or a semantic decision task (Experiment 2). The main results of the study were the same in both language directions (Spanish–Catalan and Catalan–Spanish), showing that the degree of semantic overlap (in terms of shared features) between words in different languages can modulate priming effects, regardless of the language of the prime and the task used. These results demonstrate that there is cross-language activation of shared semantic representations and, thus, that highly proficient bilinguals can have direct access to word meaning from the two languages.