Charles Perfetti
Charles Perfetti is the director of, and Senior Scientist for, the Learning and Research Development Center at the University of Pittsburgh. His research is centered on the cognitive science of language and reading processes, including but not limited to lower- and higher-level lexical and syntactic processes and the nature of reading proficiency. He conducts cognitive behavioral studies involving ERP, fMRI and MEG imaging techniques. His goal is to develop a richer understanding of how language is processed in the brain. Chinese and English word identification. Charles Perfetti focuses on recognizing specific components of reading which are generalized  across cultures. In doing so he compares the word recognition processes of Chinese and writing. Perfetti's studies which are concerned with learning across writing systems, involve neuroimaging such as fMRI and ERP. In his research titled "Sentence integration processes: An ERP study of Chinese sentence comprehension with relative clauses", Perfetti analyzed comprehension of various types of Chinese relative clauses to find out generalization and linguistic specificity of how sentence comprehension is processed. The idea of the study is based on the fact that object-extracted clauses increase in memory load which is why subject-extracted clauses are easier to  comprehend. The fact that Chinese speakers lack grammatical relationships between arguments raises questions whether if the process of remembering a words context overshadows the extraction of clausal relationships. The English language is the opposite because sentences which are processed are structure-dependent. Lexical Quality. In exploring the Lexical Quality Hypothesis Charles Perfetti focuses on analyzing the brain’s fundamentals of being able to read. In "Reading Ability: Lexical Quality to comprehension", Perfetti states, that differences in characteristics of word comprehension impacts reading ability and comprehension. High-lexical qualities partly involve the spelling of a word as well as the manipulation  of meaning about a word which allows meaning retrieval at a rapid pace. However, low quality representations of a word promote word-related difficulties in comprehension of a text. His first set of results reveals that comprehension depends on lexical skill and describes the disconnections that focus specifically on comprehension skills. As for word linguistic processing, studies reveal skill difference are found in through the analysis of confusing word meanings. The Event Related Potentials performed on rare vocabulary meaning unveil how skilled readers acquire words better and reveal stronger ERP indications of word learning. In addition, these results propose that  there are skill differences in understanding the orthographic representation of a word. ERP results also show that there are skill differences in comprehending and processing of ordinary words. Finally, they demonstrate problems for low-skilled readers with interpreting words with prior text. In doing so, Perfetti provides findings that suggest word-knowledge impacts the processing of word meaning and comprehension. His findings also focus on the importance of lexical Representations and how it facilitates differences in individuals who perform comprehension task. In his article "Learning words in Zekish: Implications for understanding Lexical Representation", He describes their studies of phonology, orthography  and comprehension. For phonology his research considers the sounds that exist in language and how they collaborate to form other words. When discussing orthography the spelling of words and how a language can facilitate the spelling of words. When analyzing comprehension, he considers lexical knowledge that is placed into a system which can provide and maintain what is represented in a text being read. Perfetti argues that words have a purpose that serve as a baseline acquiring reading skill and are important for understanding the components of a word that affect the knowledge of a word. In addition, he proposes  that writing words within a text determines the rate at which a word is encountered. Therefore, each individuals reading experience is adjusted to the rate at which words are written into a context of words personally encountered words. In discussing how lexical quality is acquired, Perfetti proposes that aspects of experiencing language can facilitate higher or lower lexical quality for word representations. This research reveals that higher lexical quality representations can support better comprehension of text. To provide evidence of this, Perfetti analyzes three types of lower lexical quality words and what they contribute to the processing of text. The  types of words consist of homographs, ambiguous words and homophones. Homographs are words that have the same spelling but two different meanings in a language, depending on how they are pronounced. For example the word bass can be pronounced one way to mean fish or another way to represent a musical instrument. When words like this are presented to a reader, no specific lexical item is activated. Instead, two lexical items activated through semantic judgment and lexical decision while naming the word. Ambiguous words consist of the same spelling but have two or more meanings. For example the word spring  can mean a season or metal coil. When ambiguous words are read, there is an activation of both meanings. Meanings for this word can mainly be acquired through the extent of bias found in the context of which the word appears word structure and the rate at which each meaning is utilized. Homophones are words that consist of two different spellings and meanings. They pose a problem for lexical quality because there is activation for both meanings and both spellings. For example air describes the atmosphere while heir describes inheritance. However, the process of disambiguate homophones differs from the process  used for ambiguous words because the spelling of homophones allows a reader to disambiguate on their own. For several semesters, Perfetti tested 800 psychology students over the course of several semesters. The students were given reading task to assess their levels of spelling, word sounding and comprehension skills. His claim was that the rate at which words are experienced and reading skill administers a readers experience with words. He found out that by making sure participants knew both meanings of homophone pairs, achievement of skilled and less skilled readers could be assessed. Furthermore, educating participants on lower exposed members of  homophones can reverse the confusion of comprehension to the point that they become higher frequency words. Learning New Words. Charles Perfetti published an article titled word "Learning: An ERP investigation of word experience effects on recognition and word processing to assess the quality learning new words". In this study, adults with various levels of reading comprehension skills learned rare unknown English words. 500 college undergrads were divided into three conditions in which they learned words that were manipulated. In the first condition (orthography-to-meaning), participants had to learn the spelling and meaning of a word. Participants in the second  condition (orthography-to-phonology) had to learn both the pronunciation and spelling of the word. For the third condition (phonology-to-meaning), these participants had to learn not only the meaning of the word, but its pronunciation as well. In the experiment, each of these conditions were followed by a learning phase that which would then assess the familiarity of the learned words. The results showed faster reaction times for learned and familiar words than that of unlearned and rare words while the response times for correct decisions were faster than incorrect decisions. There was a significant main effect for  word type, but not for word type x relatedness. This kind of word type revealed how learners were faster at responding to related trials in the orthography-to-meaning and phonology trials. The interaction for word type x correctness revealed a difference in decision times. This was found in the orthography-to-meaning and phonology-to-meaning conditions for familiar words. The results conclude that reinforcing the words orthography might help readers recognize a word in future encounters which will influence the process of incremental learning. Text Comprehension. In his article titled "Writing Strengthens Orthography and Alphabetic-Coding Strengthens Phonology  in Learning to Read Chinese", Perfetti studies the word based inference processes of text comprehension. He argues that learning how to write words may improve orthographic representations and support word-specific identification processes. The rule relates to Chinese language where the writing system promotes character-specific identification depending on accuracy representation of how a word is spelled. This experiment consisted of two studies that tested the hypothesis by analyzing learners of the Chinese language. The participants consisted of 67 Carnegie Mellon undergrad students. In the first experiment, a total of 54 traditional Chinese characters were selected to be use. The  characters would be placed into three groups matched by their spelling, stroke number, number of radicals, and English-transition rate. In the first group characters were presented in the condition for read-only and handwriting for the second group. For the third group, nothing was taught, just used for novel control stimuli. 36 characters were taught over a three days period while visual and audio files of the characters were administrated by a server. Due to the fact that participants were learners and not readers of Chinese, there was an expectation of lexical decision being the influence of learning. The  results reveal a constant learning effect in the handwriting condition more than the reading condition. The handwriting effects consisted of retrieval for English meaning. These results indicate performances in the writing condition were continuously better than the reading condition. The interpretation of this higher quality form when they are taught with handwriting. In experiment two, participants had to type in Pinyin and tone associated with character. Not only were they given three attempts but only correct or incorrect feedback was given in response. In both of the learning conditions, participants were told to match the link of each character with  its meaning and pronunciation. The results revealed a consistent effect for handwriting. The writing+ writing condition performed better on orthographic memory mapping task overall conclusion is that character writing as part of learning to read supports character reading. Learning a second language. Charles Perfetti and colleagues conducted a study called "High Proficiency in a second Language is characterized by Greater Involvement of the First Language Network: Evidence from Chinese Learners of English" to examine the processes of learning a second language. The first thing he does is talk about the assimilation and accommodation hypothesis that involve the process of learning  a second language. The assimilation hypothesis argues that second language is learned through the brains access of networks used to process the native language. Accommodation hypothesis argues that learning of a second language depends on brain structures not involve in process of the native language. Two test these hypothesis, Perfetti and colleagues examined a group of Chinese speakers who happened to be late learners with various levels of proficiency in English. The experiment was divided into 3 groups. The (ce group), (cc group) and (ee group) consisted of Chinese speaking participants who performed an English word rhyming judgment task while  fMRI was performed. Assimilation was analyzed by comparing the cc group to the ce group while accommodation was analyzed by comparing the (ee group). The study involved participants deciding whether two symbol patterns presented in sequence match or mismatched. Rhyming was seen as the same rhyme for the second character of the word while orthography was defined as having the same phonetic radical for the second character of the word.