Biomedical subjects

K I Forster

Publications and source records attributed to K I Forster.

10 recordsLinked to original sources

PubMed1997

Event-related brain potential examination of implicit memory processes: masked and unmasked repetition priming.

The proposition that cortically based perceptual representation systems (PRSs) are responsible for some implicit priming phenomena was examined by using event-related potentials (ERPs) in repetition and masked word priming. Experiment 1 used an explicit recognition task, in which repeated words replicated previous ERP repetition priming effects, whereas masked repetition priming revealed a new ERP effect with a posterior topography. Experiment 2 demonstrated ERP and behavioral priming in a lexical decision task for repetition and masked repetition priming. Topographical mapping of ERP repetition priming effects involved both early and late effects over the right and left anterior regions, whereas masked priming produced only an early ERP effect posteriorly. These results suggest differences between early and late ERP priming effects in terms of explicit recollection. Moreover, a posterior PRS may not be involved in some longer term implicit repetition priming effects.

Adolescent↗

PubMed1996

No enemies in the neighborhood: absence of inhibitory neighborhood effects in lexical decision and semantic categorization.

The effect of neighborhood density on visual word recognition was found to be facilitatory for words but inhibitory for nonwords in 3 lexical-decision experiments. However, the facilitation virtually disappeared when the task was changed to semantic categorization (animal vs. nonanimal), despite the presence of a strong frequency effect. None of these experiments showed a consistent inhibitory effect of a higher frequency neighbor. The absence of inhibitory effects suggests that competition does not play a key role in visual word recognition. The data also suggest that the neighborhood density effect is not an access effect but is a task-dependent effect instead.

Adult↗

PubMed1994

Computational modeling and elementary process analysis in visual word recognition.

An attempt is made to isolate the assumptions that make a connectionist approach to visual word recognition distinctive. These include the commitment to distributed representations, the claim that there is no distinction between lexical and nonlexical systems in the naming task, and the claim that it is possible to map from orthography to meaning without using localized representations. It is argued that merely demonstrating that a network model can perform these tasks is not sufficient and that a detailed theory of how the network performs its tasks must accompany the simulation, because a simulation is not equivalent to an explanation. It is argued that further progress requires detailed modeling and experimental study of the elementary processes assumed to be involved in networks and that it is premature to dismiss alternative models of lexical access such as serial search models.

Humans↗

PubMed1994

Bodies, antibodies, and neighborhood-density effects in masked form priming.

Facilitatory priming effects due to similarity of orthographic form are obtained for high-N target words provided that they have low-frequency bodies and the body is shared between the prime and target (e.g., perd-HERD). Conversely, it is shown that low-N target words show priming regardless of the frequency of the body, provided that the prime and target do not share the same body (e.g., drice-DRIVE). If the body is shared, then priming occurs only for targets with low-frequency bodies. These results suggest that neighborhood density should be defined in terms of both individual letter units and subsyllabic units and that both types of density jointly determine priming.

Decision Making↗

PubMed1987