Biomedical subjects

J S Bowers

Publications and source records attributed to J S Bowers.

8 recordsLinked to original sources

PubMed2000

The modality-specific and -nonspecific components of long-term priming are frequency sensitive.

Five experiments were carried out to test the claim that the modality-specific and modality-nonspecific components of long-term priming are differentially sensitive to word frequency, with the specific component being less affected. In contrast with this claim, specific and nonspecific priming were similarly reduced for high-frequency words in three lexical decision and two perceptual identification experiments. These findings highlight the important role of frequency in modulating priming as well as provide a basic constraint for future theories of priming. In addition, the roles of task and student population in modulating priming are examined.

Adult↗

PubMed2000

In defense of abstractionist theories of repetition priming and word identification.

There is a great deal of interest in characterizing the representations and processes that support visual word priming and written word identification more generally. On one view, these phenomena are supported by abstract orthographic representations that map together visually dissimilar exemplars of letters and words (e.g., the letters A/a map onto a common abstract letter code a*). On a second view, orthographic codes consist in a collection of episodic representations of words that interact in such a way that it sometimes looks as if there are abstract codes. Tenpenny (1995) contrasted these general approaches and concluded by endorsing the episodic account, arguing that no evidence demands that we posit abstract orthographic representations. This review reconsiders the evidence and argues that a variety of priming and nonpriming research strongly supports the conclusion that abstract orthographic codes exist and support priming and word identification. On this account, episodic representations are represented separately from abstract orthographic knowledge and contribute minimally to these functions.

Cognition↗

PubMed2000

Orthography plays a critical role in cognate priming: evidence from French/English and Arabic/French cognates.

A series of three experiments was carried out in order to better characterize the representations that support long-term cognate priming. In Experiment 1, robust priming was obtained between orthographically similar French/English cognates in bilingual speakers, and this priming was mediated, in part, by orthographic codes, given that priming for these items was dramatically reduced following a study-test modality shift. In Experiment 2, no priming was obtained between the same set of French/English cognates in monolingual English speakers. Finally, in Experiment 3, priming for orthographically unrelated Arabic/French cognates was no larger than cross-modal priming, suggesting that these effects were mediated by nonorthographic representations. The role of orthography in supporting cognate priming is discussed.

Adult↗

PubMed1998

Orthographic, phonological, and articulatory contributions to masked letter and word priming.

A series of experiments assessed masked priming for letters and words that are visually similar (SIM) and dissimilar (DIS) in upper- and lowercase formats. For letters, robust DIS priming was obtained in a naming task, but this priming did not extend to a variety of non-naming tasks. For words, robust DIS priming was obtained in both naming and non-naming tasks. SIM letter and word priming extended to all tasks, but the effects were generally small for letters. The restricted set of conditions for DIS letter priming suggests that this priming is mediated by phonological-articulatory processes, and the generality of DIS word priming argues that abstract orthographic codes mediate these effects. Consistent with this conclusion, priming between homophones (for both letters and words) was found in a naming task, but little word homophone priming was obtained in a lexical decision task.

Humans↗

PubMed1997

The potential role of spinal cord cyclooxygenase-2 in the development of Freund's complete adjuvant-induced changes in hyperalgesia and allodynia.

Chronic inflammatory conditions produce a state of hyperalgesia which is evident from a few hours to days after administration of an inflammatory stimulus. The molecular mechanisms involved in the initiation of hyperalgesia are not well understood and in this study we have investigated the role of prostaglandins in this process in the rat. Unilateral intraplantar injection of Freund's complete adjuvant produces an immediate localized swelling (oedema) with the development of altered pain responses in the ipsilateral paw such as a reduced threshold to noxious stimuli (hyperalgesia) and lowered thresholds such that normally innocuous stimuli produce a pain response (allodynia). We have monitored levels of cyclooxygenase messenger RNA and prostaglandins in lumbar spinal cord in parallel with these behavioural responses (oedema, hyperalgesia and allodynia) and identified a marked increase in cyclooxygenase-2 messenger RNA (3-fold), maximal at 2-4 h after Freund's complete adjuvant, followed by a significant increase in 6-keto prostaglandin F1alpha and prostaglandin E2 which is maximal by 8 h. Pretreatment of animals with the unselective cyclooxygenase inhibitor indomethacin attenuated oedema (approximately 40%) and allodynia (80-100%), but had no effect on the development of mechanical hyperalgesia. Pretreatment with the cyclooxygenase-2 selective inhibitors DuP 697, flosulide and SC58125 also attenuated allodynia (by 80-100%) but had no effect on the development of oedema or mechanical hyperalgesia. The marked increase in cyclooxygenase-2 messenger RNA in the lumbar spinal cord following intraplantar Freund's complete adjuvant suggests that the cyclooxygenase enzyme and its product may have a role in the adaptive response that occurs in the lumbar spinal cord during a peripheral inflammatory reaction. Pharmacological analysis reveals that prostaglandins are directly involved in the development of allodynia. However, these studies show that the development of mechanical hyperalgesia does not require the production of prostaglandins indicating that more than one pathway mediates the altered pain responses associated with a peripheral inflammatory lesion.

Animals↗

PubMed1996

Different perceptual codes support priming for words and pseudowords: was Morton right all along?

A perceptual-identification task was used to assess priming for words and pseudowords that in their upper- and lowercase formats share either few (high-shift items) or many (low-shift items) visual features. Equivalent priming was obtained for high-shift words repeated in the same case and in a different case, and this priming was greatly reduced when there was a study-test modality shift. Accordingly, the cross-case priming was mediated in large part by modality-specific perceptual codes. By contrast, priming for high-shift pseudowords was greatly reduced following the case manipulation, as was so for high-shift words when they were randomly intermixed with pseudowords. Low-shift items were not affected by the case manipulation. On the basis of the overall pattern of results, the author argues that different mechanisms mediate priming for words and pseudowords and that J. Morton (1979) was essentially correct in his characterization of word priming.

Humans↗

PubMed1994

Does implicit memory extend to legal and illegal nonwords?

In 4 experiments, implicit and explicit memory for words and nonwords were compared. In Experiments 1-2 memory for words and legal nonwords (e.g., kers) was assessed with an identification (implicit) and a recognition (explicit) memory task: Robust priming was obtained for both words and nonwords, and the priming effects dissociated from explicit memory following a levels-of-processing manipulation (Experiment 1) and following a study-test modality shift (Experiment 2). In Experiment 3, priming for legal and illegal nonwords (e.g., xyks) was observed on an identification task, and the effects dissociated from explicit memory following a levels-of-processing manipulation. Finally, in Experiment 4, significant inhibitory priming for legal nonwords was observed when a lexical-decision task was used. Results suggest that implicit memory can extend to legal and illegal nonwords. Implications for theories of implicit memory are discussed.

Acoustic Stimulation↗

PubMed1990

Implicit memory and test awareness.

In three experiments we examined whether normal subjects can perform an implicit test without becoming aware that the test items were previously encountered in the study phase of the experiment. Experiment 1 assessed single word priming with the stem completion task, and subjects who reported awareness/unawareness that the test items were previously encoded in the study task showed equivalent priming. Experiments 2a-c and 3 assessed associative priming with the stem completion task, and in this case, only subjects who were aware that the test items were previously encountered showed associative priming effects. These findings suggest that single word priming and associative priming reflect different memory processes because the former and not the latter effect can be observed in unaware subjects.

Adult↗