Biomedical subjects

Marcus Taft

Publications and source records attributed to Marcus Taft.

5 recordsLinked to original sources

PubMed2004

The nature of the mental representation of radicals in Chinese: a priming study.

Using a priming procedure, 4 experiments were carried out to investigate the effects of a short preexposure of a prime that was a radical or contained radicals identical to the target. Significant facilitation was found when the target contained the prime as a radical, although only for low-frequency targets which did not arise merely as a result of graphical similarity. Facilitation also occurred when the prime and target shared a radical in the same position but not when in different positions. When the prime and target had exactly the same radicals but in different positions, however, the priming effect was inhibitory. This set of results suggests that simple characters (radicals) and complex characters are represented at a different level.

Comprehension↗

PubMed2004

Morphological decomposition and the reverse base frequency effect.

If recognition of a polymorphemic word always takes place via its decomposition into stem and affix, then the higher the frequency of its stem (i.e., base frequency) the easier the lexical decision response should be when frequency of the word itself (i.e., surface frequency) is controlled. Past experiments have demonstrated such a base frequency effect, but not under all circumstances. Thus, a dual pathway notion has become dominant as an account of morphological processing whereby both decomposition and whole-word access is possible. Two experiments are reported here that demonstrate how an obligatory decomposition account can handle the absence of base frequency effects. In particular, it is shown that the later stage of recombining the stem and affix is harder for high base frequency words than for lower base frequency words when matched on surface frequency, and that this can counterbalance the advantage of easier access to the higher frequency stem. When the combination stage is crucial for discriminating the word items from the nonword items, a reverse base frequency effect emerges, revealing the disadvantage at this stage for high base frequency words. Such an effect is hard for the dual-pathway account to explain, but follows naturally from the idea of obligatory decomposition.

Humans↗

PubMedDate not supplied

Sonority constraints on onset-rime cohesion: evidence from native and bilingual Filipino readers of English.

Research in English suggests that syllables can be analyzed in terms of two subunits-the onset (defined as the initial consonant or consonant cluster) and the rime (the unit formed by the vowel and following consonant/s). This study investigated whether nonnative readers of English, which in the case of the present study were native Filipino speakers, also make use of onset-rime units, particularly when some features of their native language (namely infixation and reduplication) appear to foster no awareness of such units. In two lexical decision experiments, monosyllabic English words were presented, divided in between their first and second consonants (e.g., B LIND), at their onset-rime boundary (e.g., BL IND), or at their antibody boundary (e.g., BLI ND). Results indicated that the processes of infixation and reduplication did not affect the English word processing of native Filipino speakers. Rather, results for both native Filipino and native English speakers suggest that onsets composed of an "s + consonant" sequence (e.g., STAMP) are less cohesive than onsets comprised of a stop-liquid sequence (e.g., BLIND). It was concluded that not only may sonority constraints underlie onset cohesiveness, but that such phonetic properties may also be involved in visual word recognition.

Humans↗

PubMedDate not supplied

Orthographic processing of polysyllabic words by native and nonnative English speakers.

How polysyllabic English words are analyzed in silent reading was examined in three experiments by comparing lexical decision responses to words physically split on the screen. The gap was compatible either with the Maximal Onset Principle or the Maximal Coda Principle. The former corresponds to the spoken syllable (e.g., ca det), except when the word has a stressed short first vowel (e.g., ra dish), while the reverse is true for the latter (giving cad et and rad ish). Native English speakers demonstrated a general preference for the Max Coda analysis and a correlation with reading ability when such an analysis did not correspond with the spoken syllable. Native Japanese speakers, on the other hand, showed a Max Onset preference regardless of the type of word, while native Mandarin Chinese speakers showed no preference at all. It is concluded that a maximization of the coda is the optimal representation of polysyllabic words in English and that poorer native readers are more influenced by phonology than are better readers. The way that nonnative readers mentally represent polysyllabic English words is affected by the way such words are structured in their native language, which may not lead to optimal English processing.

Adult↗

PubMedDate not supplied

The processing of morpheme-like units in monomorphemic words.

The word virus is not normally considered polymorphemic, yet it is clearly both semantically and orthographically related to the word viral. Thus, the subunit vir takes on the role of a bound morpheme. In contrast, the words future and futile also share a subunit (fut), but are semantically unrelated. The reported experiment demonstrates facilitation in a masked priming experiment for the semantically related pairs that share an initial orthographic subunit (e.g., virus-viral), but not for the semantically unrelated pairs (e.g., future-futile). Whether the subunit was pronounced the same way in the prime and target was shown to be irrelevant. Furthermore, semantic relatedness was insufficient to produce priming when orthography was not shared. It was concluded that, while the units of processing within the orthographic system may be the same for the two types of item, their representation at a higher level may depend on the correlation between form with meaning. For example, virus and viral might share a higher level representation and thus facilitate each other, whereas future and futile might be represented separately at that higher level and even compete with each other.

Humans↗