Online research in philosophy

Priming and recollection are expressions of human memory mediated by different brain events. These brain events were monitored while people discriminated words from nonwords. Mean response latencies were shorter for words that appeared in an earlier study phase than for new words. This priming effect was reduced when the letters of words in study-phase presentations were presented individually in succession as opposed to together as complete words. Based on this outcome, visual word-form priming was linked to a brain potential recorded from the scalp over the occipital lobe about 450 ms after word onset. This potential differed from another potential previously associated with recollection, suggesting that distinct operations associated with these two types of memory can be monitored at the precise time that they occur in the human brain.

The distinction between rules and similarity is central to our understanding of much of cognitive psychology. Two aspects of existing research have motivated the present work. First, in different cognitive psychology areas we typically see different conceptions of rules and similarity; for example, rules in language appear to be of a different kind compared to rules in categorization. Second, rules processes are typically modeled as separate from similarity ones; for example, in a learning experiment, rules and similarity influences would be described on the basis of separate models. In the present article, I assume that the rules versus similarity distinction can be understood in the same way in learning, reasoning, categorization, and language, and that a unified model for rules and similarity is appropriate. A rules process is considered to be a similarity one where only a single or a small subset of an object's properties are involved. Hence, rules and overall similarity operations are extremes in a single continuum of similarity operations. It is argued that this viewpoint allows adequate coverage of theory and empirical findings in learning, reasoning, categorization, and language, and also a reassessment of the objectives in research on rules versus similarity. Key Words: categorization; cognitive explanation; language; learning; reasoning; rules; similarity.

The correlative coactivation of sensory inputs, Hebb's “second rule,” probably plays a critical role in the formation of word representations in the neocortex. It is essential to the acquisition of word meaning. The acquisition of semantic memory is inseparable from that of individual memory, and therefore the two probably share the same neural connective substrate. Thus, “content” words are represented mainly in postrolandic cortex, where individual perceptual memories are also represented, whereas “action” words are represented in frontal cortex, with executive memories. The activation of a memory network may not necessarily entail the high-frequency oscillatory firing of its cells, though reverberation remains a plausible mechanism of short-term memory.

Presentation times of study words presented in the Deese/Roediger and McDermott (DRM) paradigm varied from 20 to 2000 ms per word in an attempt to replicate the false memory effect following extremely short presentations reported by . Both in a within-subjects design (Experiment 1) and in a between-subjects design (Experiment 2) subjects showed memory for studied words as well as a false memory effect for related critical lures in the 2000-ms condition. However, in the conditions with shorter presentation times (20 ms in Experiment 1; 20 and 40 ms in Experiment 2) no memory for studied words, nor a false memory effect was found. We argue that there is at present no strong evidence supporting the claim for a nonconscious basis of the false memory effect.

The distinction between regular and irregular morphology is not clear-cut enough to suggest two distinct modular structures. Instead, regularity is tied directly to the type frequency of a pattern. Evidence from experiments as well as from naturally occurring sound change suggests that even regular forms have lexical storage. Finally, the development trajectory entailed by the dual-processing model is much more complex than that entailed by associative network models.

We report an experiment that unambiguously shows an effect of full-form frequency for fully regular Dutch inflected verbs falling into Clahsen's “default” category, negating Clahsen's claim that regular complex words in the default category are not stored.

The heated debate over whether there is only a single mechanism or two mechanisms for morphology has diverted valuable research energy away from the more critical questions about the neural computations involved in the comprehension and production of morphologically complex forms. Cognitive neuroscience data implicate many brain areas. All extant models, whether they rely on a connectionist network or espouse two mechanisms, are too underspecified to explain why more than a few brain areas differ in their activity during the processing of regular and irregular forms. No one doubts that the brain treats regular and irregular words differently, but brain data indicate that a simplistic account will not do. It is time for us to search for the critical factors free from theoretical blinders.

When referring to the organization of the mental lexicon, the distinction between combinatorial rules and lexical listing for regularly versus irregularly inflected words should be further developed to account for subregular morphological processes. Moreover, the distinction may be more or less appropriate depending on the lexical component under consideration, and it is subject to interplay with other factors that are relevant in determining the representational structure of the lexical system.

According to the ‘word/rule’ account, regular inflection is computed by a default, symbolic process, whereas irregular inflection is achieved by associative memory. Conversely, patternassociator accounts attribute both regular and irregular inflection to an associative process. The acquisition of the default is ascribed to the asymmetry in the distribution of regular and irregular tokens. Irregular tokens tend to form tight, well-defined phonological clusters (e.g. sing-sang, ring-rang), whereas regular forms are diffusely distributed throughout the phonological space. This distributional asymmetry is necessary and sufficient for the acquisition of a regular default. Hebrew nominal inflection challenges this account. We demonstrate that Hebrew speakers use the regular masculine inflection as a default despite the overlap in the distribution of regular and irregular Hebrew masculine nouns. Specifically, Experiment 1 demonstrates that regular inflection is productively applied to novel nouns regardless of their similarity to existing regular nouns. In contrast, the inflection of irregular sounding nouns is strongly sensitive to their similarity to stored irregular tokens. Experiment 2 establishes the generality of the regular default for novel words that are phonologically idiosyncratic. Experiment 3 demonstrates that Hebrew speakers assign the default regular inflection to borrowings and names that are identical to existing irregular nouns. The existence of default inflection in Hebrew is incompatible with the distributional asymmetry hypothesis. Our findings also lend no support for a type-frequency account. The convergence of the circumstances triggering default inflection in Hebrew, German and English suggests that the capacity for default inflection may be general. © 1999 Elsevier Science B.V. All rights reserved..

Most evidence for the role of regular inflection as a default operation comes from languages that confound the morphological properties of regular and irregular forms with their phonological characteristics. For instance, regular plurals tend to faithfully preserve the base’s phonology (e.g., rat-rats), whereas irregular nouns tend to alter it (e.g., mouse- mice). The distinction between regular and irregular inflection may thus be an epiphenomenon of phonological faithfulness. In Hebrew noun inflection, however, morphological regularity and phonological faithfulness can be distinguished: Nouns whose stems change in the plural may take either a regular or an irregular suffix, and nouns whose stems are preserved in the plural may take either a regular or an irregular suffix. We use this dissociation to examine two hallmarks of default inflection: its lack of dependence on analogies from similar regular nouns, and its application to nonroots such as names. We show that these hallmarks of regularity may be found whether or not the plural form preserves the stem faithfully: People apply the regular suffix to novel nouns that don’t resemble existing nouns, and to names that sound like irregular nouns, regardless of whether the stem is ordinarily preserved in the plural of that family of nouns. Moreover, when they pluralize names (e.g., the Barak-Barakim), they do not apply the stem changes that are found in their homophonous nouns (e.g., barak-brakim “lightning”), replicating an effect found in English and German. These findings show that the distinction between regular and irregular phenomena cannot be reduced to differences in the kinds of phonological changes associated with those phenomena in English. Instead, regularity and irregularity must be distinguished in terms of the kinds of mental computations that effect them: symbolic operations versus memorized idiosyncrasies. A corollary is that complex words are not generally dichotomizable as “regular” or “irregular”; different aspects of a word may be regular or irregular depending on whether they violate the rule for that aspect and hence must be stored in memory..