Michael T. Ullman

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Language comprises a lexicon for storing words and a grammar for generating rule-governed forms. Evidence is presented that the lexicon is part of a temporal-parietalhnedial-temporal "declarative memory" system and that granlmatical rules are processed by a frontamasal-ganglia "procedural" system. Patients produced past tenses of regular and novel verbs(More)
The structure of the brain and the nature of evolution suggest that, despite its uniqueness, language likely depends on brain systems that also subserve other functions. The declarative/procedural (DP) model claims that the mental lexicon of memorized word-specific knowledge depends on the largely temporal-lobe substrates of declarative memory, which(More)
  • M T Ullman
  • Journal of psycholinguistic research
  • 2001
Our use of language depends upon two capacities: a mental lexicon of memorized words and a mental grammar of rules that underlie the sequential and hierarchical composition of lexical forms into predictably structured larger words, phrases, and sentences. The declarative/procedural model posits that the lexicon/grammar distinction in language is tied to the(More)
Children extend regular grammatical patterns to irregular words, resulting in overregularizations like comed, often after a period of correct performance ("U-shaped development"). The errors seem paradigmatic of rule use, hence bear on central issues in the psychology of rules: how creative rule application interacts with memorized exceptions in(More)
What are the psychological, computational and neural underpinnings of language? Are these neurocognitive correlates dedicated to language? Do different parts of language depend on distinct neurocognitive systems? Here I address these and other issues that are crucial for our understanding of two fundamental language capacities: the memorization of words in(More)
Specific Language Impairment (SLI) has been explained by two broad classes of hypotheses, which posit either a deficit specific to grammar, or a non-linguistic processing impairment. Here we advance an alternative perspective. According to the Procedural Deficit Hypothesis (PDH), SLI can be largely explained by the abnormal development of brain structures(More)
We used event-related functional magnetic resonance imaging to identify brain regions involved in syntactic and semantic processing. Healthy adult males read well-formed sentences randomly intermixed with sentences which either contained violations of syntactic structure or were semantically implausible. Reading anomalous sentences, as compared to(More)
What are the computational and representational bases of the mental lexicon of words, and of the rules of grammar which productively combine lexical forms into larger words, phrases and sentences? ‘‘Dual-system’’ theories posit that lexical forms with non-compositional (arbitrary) sound-meaning pairings are stored in memory, whereas compositional structures(More)
This study evaluates the input-processing deŽcit/single system and the grammar-speciŽc deŽcit/dual system models to account for past tense formation in impaired and normal language development. We investigated regular and irregular past tense formation of 60 real and novel regular and irregular verbs in ‘‘Grammatical (G)-SLI’’ children (aged 9:3 to 12:10)(More)