I present evidence that masked repetition priming of word identification can be modulated by post-prime cues. Cues consisted of targets presented in black, with repetition and unrelated primes equally likely for such targets, or in a color that was correlated with type of prime (e.g., red = repetition prime, green = unrelated prime). There was an increase in response latency for targets with unrelated primes and a decrease in response latency to targets with repetition primes when target color was correlated with type of prime. In this correlation condition, subjects exhibited a larger reliance on the prime for target processing. In the condition where target color was unrelated to prime type, subjects had less reliance on the prime and processed the target more independently.

The purpose of this dissertation is to investigate the extent to which there is consistent evidence pertaining to the prime lexicality effect. Theoretical claims about the nature of this effect, in which masked nonword form primes produce greater facilitation than word form primes, have been hotly debated in the masked priming literature. Here, there are two major conflicting accounts of visual word recognition to consider. Cascaded activation approaches such as the Interactive Activation model rely on competition between word units to account for word recognition. This view predicts inhibitory effects for word form primes due to competition between word units for the prime and target. In contrast, proponents of the Search Model have maintained that elements in the process of verifying visual input suggest that word primes should produce neither facilitatory nor inhibitory effects during masked presentation. Evidence that is consistent with both approaches has been reported in the literature. A 1998 study by Forster and Veres looked at long words using a masked lexical decision task and demonstrated strong facilitation from nonword primes and no effect for word primes. A 2006 paper for Davis and Lupker, however, reported that the nonword prime facilitation that they observed using the same task was accompanied by strong word prime inhibition. The presence of this inhibitory effect seems to support the interactive activation account, but it remains unclear why inhibitory effects such as these were not seen in the Forster and Veres work. The present study sought to explore the reliability of the effects that are generated by word form primes. In particular, the different types of stimuli used in the conflicting papers (i.e. long versus short items) were contrasted. Evaluations regarding their relative discrimination difficulty and performance during masked lexical decision were conducted. The investigation revealed that there is indeed a difference between the output provided by those different stimulus types and that context effects emerge when they are presented together in the same experiment. The implications of these findings for the various views on visual word recognition are discussed.

Letter position plays an important role in lexical access. But are some positions more important than the others? Findings from numerous studies support the notion that in lexical access, initial letters produce strongest activation, which weakens towards the end of the word. In order to create a metric for computing the activation produced by each letter position in a correctly spelled word versus a word in which some or all letters are transposed, the formula for calculating a word's orthographic match coefficient (OMC) was developed and tested. Utilizing the masked priming paradigm and a lexical decision task, Experiments 1-5 test the accuracy and reliability of the OMC predictions, and look at neighborhood density in conjunction with different types of letter movement. Results from these experiments provide empirical support for the OMC as a reliable predictor of priming that involves transposed letters, and offer insight into possible mechanisms of word recognition.

Most research in word recognition uses words that already exist in the reader's lexicon, and it is therefore of interest to see whether newly learned words are represented and processed in the same way as already known words. For example, are newly learned words immediately represented in a special form of lexical memory, or is there a gradual process of assimilation? As for L2 language learners, are newly learned words incorporated into the same processing system that serves L1, or are they represented quite independently?The current study examines this issue by testing for the existence of the Prime Lexicality Effect (PLE) observed in masked priming experiments (Forster & Veres, 1998). Strong form priming was found with nonword primes (e.g., contrapt-CONTRACT), but not with word primes (e.g., contrast-CONTRACT). This effect is generally assumed to result from competition between the prime and the target. So if the readers had been trained to treat "contrapt" as a new word, would it now function like a word and produce much weaker priming? Elgort (2007) demonstrated such an effect with unmasked primes with L2 bilinguals. The current study investigates the PLE in both L1 and L2 bilinguals under different training conditions. When the training program involves mere familiarization (learning to type the words), a PLE was found with visible primes, but not with masked primes, which suggests that unmasked PLE is not the best indicator of lexicalization. In the case of "real" acquisition where the new word is given a definition and a picture of the object it refers to, and learning is spread over two weeks, a clear PLE was obtained. However, when the same experiment was carried out on Chinese-English bilinguals using the same English materials, completely opposite results were obtained. The learning enhanced priming, rather than reducing it, suggesting that the L2 lexicon might differ qualitatively from the L1 lexicon. The implications of these results for competitive theories of lexical access are discussed, and alternative explanations are considered.

This dissertation focuses on the unique aspects of Maltese morphology brought about by its genetic and geographic history. The experiments conducted and described here build on past research in Indo-European languages and new research in other Semitic languages to determine how different word formation systems function. Applying experimental techniques to the study of Maltese is crucial for two reasons. First, though Maltese is a Semitic language, recent extensive contact with English has greatly impacted its vocabulary and the structure of its verbs. Though the effects of persistent language contact is pervasive, clear and systematic differences may be observed between native Semitic verbs and those borrowed from English. Secondly, unlike other Semitic languages, the Maltese writing system uses the Roman alphabet. This allows for tests that require the reading of written stimuli to be performed in the same writing system as previous studies in Indo-European languages, eliminating a number of confounding factors.A masked priming experiment asked Maltese speakers to judge whether or not test items were words of their language. The test items included real and nonce verbs of both Semitic and English origin. Accuracy rates and reaction time were recorded and compared across speakers. The results of this experiment support the psychological salience of the consonantal root as a unit of lexical organization.An elicitation experiment asked native speakers of Maltese to provide a verb form that corresponded to a given noun or adjective. The test items were nouns of Semitic and English origin and non-words constructed to resemble such nouns. Responses were broadly transcribed and analyzed for their similarity to the expected patterns. The results show that speakers are able to use two morphological strategies to form new words. The factors affecting the choice between morphological systems include linguistic structure and social variables.Collectively, this pair of experiments indicate that the consonantal root is a viable morphological and psychological unit of lexical organization, supporting a search-based approach to lexical access. Furthermore, speakers are able to form new words on the basis of whole words, showing that this level of organization must also be present to facilitate lexical access.

In general, L2 learners have great difficulty mastering aspects of grammar in the second language. For example, Chinese-speaking ESL learners often fail to mark past tense in their speaking and writing (Aaronson & Ferres, 1987; Bayley, 1991; Bean & Gergen, 1990; Jia & Fuse, 2007; Krashen & Pon, 1975; Lardiere, 1998; Wei, 2000), and there are some suggestions in the literature that Chinese learners of English never master English tense (Lardiere, 1998). One question that arises is whether the failure to learn to use the past tense is due to a failure of competence or a failure of performance. If the former, then Chinese-speaking ESL learners should show such failures in all tasks including comprehension tasks.However, little research has investigated L2 comprehension of tense marking in reading. The studies (Gass, 2001; Guillelmon & Grosjean, 2001; Jiang, 2004, 2007) have showed that late L2 learners are not sensitive to certain types of grammatical marking. They have poor inflectional comprehension. It is possible that Chinese English-language learners are insensitive to grammatical violation involving tense during reading. This dissertation tests this idea.A group of English-proficient college students from Fu-Jen University in Taiwan was tested in a number of tasks. In paper-and-pencil tests, Chinese English-language learners showed knowledge of the past tense forms and the appropriate contexts for their usage. This suggests that past tense marking is learnable. Chinese English-language learners can acquire this knowledge. Does the relative mastery of past tense show up in comprehension in a similar L2 population? A reading comprehension test that measured reading time to sequential segments of a sentence indicated that unlike native speakers of English who were tested, Chinese English-language learners were insensitive to grammatical violation involving tense. This finding is consistent with the other studies, indicating that L2 learners are insensitive to grammatical marking during reading.Overall, it appears that high-functioning Chinese English-language learners can learn almost the proper way to use tense, but fail to do so during performance.

As the popularity of digitally based communication devices increases, so does the propensity for individuals to find clever ways to convey messages in a shorter amount of space and time. Often, individuals use word or phrase shortening techniques known collectively as text-speak. A majority of investigations into the topic of text-speak have only focused on the potential impact text-speak may have on literacy or scholastic achievement (Crystal, 2008; Pinker 1994; Thurlow, 2003). However, there is a void in empirical investigation into how individuals create text-speak and more importantly how they process it (Farrell & Lyddy, 2012). The primary aim of this dissertation is to systematically investigate text-speak using various methodological techniques to gain a better understanding of how people create text-speak and explore how it elicits meaningful comprehension. An additional aim of this dissertation is to determine whether processing text-speak comes at a cognitive cost.

Thesis (Ph.D.)--Tufts University, 2004. / Adviser: Phillip J. Holcomb. Submitted to the Dept. of Psychology. Includes bibliographical references (leaves 211-216). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Visual information can be processed by humans both consciously and unconsciously. Under conscious conditions the humans are aware of the input, and thus can process it according to their goals. However in unconscious conditions participants remain unaware of the input, as evident from their chance accuracy when judging about the input. It has been shown that although participants may not consciously perceive subliminal input, the input can be processed automatically. Masked priming is an experimental paradigm to investigate unconscious visual processing. In this paradigm the input is presented for a very brief duration, often temporally sandwiched between a pre- and a post-mask. In this thesis, I and we mostly applied the masked-priming paradigm to study human unconscious visual processing using words and face images as input. We conducted five studies to understand unconscious visual processing and compare it with conscious processing. Our first study is about the accurate measurement of the visibility of subliminally presented visual input. In the second study, we provide a test-case for the embodied cognition theory using subliminal words. The third study is concerned with conflict control under aware and unaware conditions. In our fourth study, we tried to understand the role of subcortical structures in subliminal face processing. The fifth study is concerned with relations between space and valence priming effects. Together our findings further the understanding of unconscious and conscious visual processing.

The present dissertation aims to evaluate the phenomenon of visual masking as a tool for studying visual awareness focusing on two-alternative forced choice (2AFC) discrimination tasks. Two existing theories of masking - Bachmann's (1984) perceptual retouch theory and Marcel's (1983) recovery theory - are discussed along with the global neuronal workspace theory of awareness (Baars. 1989; Dehaene, Kerszberg, & Changeux, 1998). Performance accuracy on Semantic discrimination is compared to that on Orthographic discrimination as an indication of a potential difference between semantic and orthographic processing of masked word stimuli presented for 40 ms and 50 ms. This is further compared to an e-detection task previously used as an indicator of awareness in some masked priming experiments. Together, these tasks are further evaluated in terms of their relationship with participants' subjective reports collected in the form of confidence ratings. The implications and predictions drawn from the theories of masking and visual awareness as well as the notion of partial awareness (Kouider & Dupoux, 2001) are assessed taking into account the data obtained in the current experiments.The relevance of these data for masked priming is determined by performing a comparison between 2AFC discrimination and detection tasks, and the lexical decision task. An ERP study is also presented, in which Semantic and Orthographic discrimination as well as e-detection are paired with confidence ratings and electrophysiological recordings in search of an ERP component that can be correlated with both subjective (confidence) and objective (performance) measures of awareness. A binding account of visual awareness with special attention paid to visual masking is proposed and compared to the three existing theories.