Performance of rats on a discrimination operant alley task discriminated

An automated discriminated operant alley apparatus is described. Data from four rat strains indicate that the light-dark choice is learned by both pigmented and albino rats. The task requires a minimum of experimenter time and allows initial acquisition to be recorded without the interference of a shaping procedure.     

Base word Frequency and Pseudohomophone Naming

The advantage of naming pseudohomophones over non-pseudohomophones has been interpreted as reflecting the contribution of whole-word lexical representations in phonological coding. A whole-word interpretation was further supported by Taft and Russell (1992), who reported a pseudohomophone frequency effect such that pseudohomophones were named faster if they corresponded to high- than to low-frequency base-words (e.g. poast vs. hoast ). Experiment 1 replicated this pseudohomophone frequency effect using the Taft and Russell items. Further analyses showed, however, that the pseudohomophones in Taft and Russell's high-frequency group were more orthographically similar to words than the pseudohomophones in the low-frequency group. These differences in orthography may have been the cause of the 'frequency' effects. In Experiment 2, a new set of high- and low-frequency pseudohomophones was constructed that were matched on orthographic factors (i.e. SPBF and N). With these items, a standard pseudohomophone advantage was found such that pseudohomophones were named faster and more accurately than non-pseudohomophones. However, in contrast to Taft and Russell's results, pseudohomophone naming was not related to base-word frequency. We conclude that the pseudohomophone advantage occurs at a postlexical stage in non-word naming.     

Epistemological Disjunctivism and Introspective Indiscriminability

Philosophia - According to Duncan Pritchard’s Philosophical Issues, 21(1), 434–455, (2011, 2012, 2015)version of epistemological disjunctivism, in paradigm cases of perceptual...     

Understanding evaluation of faces on social dimensions

People reliably and automatically make personality inferences from facial appearance despite little evidence for their accuracy. Although such inferences are highly inter-correlated, research has traditionally focused on studying specific traits such as trustworthiness. We advocate an alternative, data-driven approach to identify and model the structure of face evaluation. Initial findings indicate that specific trait inferences can be represented within a 2D space defined by valence/trustworthiness and power/dominance evaluation of faces. Inferences along these dimensions are based on similarity to expressions signaling approach or avoidance behavior and features signaling physical strength, respectively, indicating that trait inferences from faces originate in functionally adaptive mechanisms. We conclude with a discussion of the potential role of the amygdala in face evaluation.     

Appetitive memory reconsolidation depends upon NMDA receptor-mediated neurotransmission

Memory persistence is a dynamic process involving the reconsolidation of memories after their reactivation. Reconsolidation impairments have been demonstrated for many types of memories in rats, and signaling at N-methyl-d-aspartate (NMDA) receptors appears often to be a critical pharmacological mechanism. Here we investigated the reconsolidation of appetitive pavlovian memories reinforced by natural rewards. In male Lister Hooded rats, systemic administration of the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-SH-dibenzo{a,d}cyclohepten-5,10-imine maleate (MK-801, 0.1 mg/kg i.p.) either before or immediately following a brief memory reactivation session abolished the subsequent acquisition of a new instrumental response with sucrose conditioned reinforcement. However, only when injected prior to memory reactivation was MK-801 effective in disrupting the maintenance of a previously-acquired instrumental response with conditioned reinforcement. These results demonstrate that NMDA receptor-mediated signaling is required for appetitive pavlovian memory reconsolidation.     

Harmonising natural deduction

Prawitz proved a theorem, formalising ‘harmony’ in Natural Deduction systems, which showed that, corresponding to any deduction there is one to the same effect but in which no formula occurrence is both the consequence of an application of an introduction rule and major premise of an application of the related elimination rule. As Gentzen ordered the rules, certain rules in Classical Logic had to be excepted, but if we see the appropriate rules instead as rules for Contradiction, then we can extend the theorem to the classical case. Properly arranged there is a thoroughgoing ‘harmony’, in the classical rules. Indeed, as we shall see, they are, all together, far more ‘harmonious’ in the general sense than has been commonly observed. As this paper will show, the appearance of disharmony has only arisen because of the illogical way in which natural deduction rules for Classical Logic have been presented.     

Object-Based Visual Selection: Evidence From Perceptual Completion

A large body of evidence suggests that visual attention selects objects as well as spatial locations. If attention is to be regarded as truly object based, then it should operate not only on object representations that are explicit in the image, but also on representations that are the result of earlier perceptual completion processes. Reporting the results of two experiments, we show that when attention is directed to part of a perceptual object, other parts of that object enjoy an attentional advantage as well. In particular, we show that this object-specific attentional advantage accrues to partly-occluded objects and to objects defined by subjective contours. The results corroborate the claim that perceptual completion precedes object-based attentional selection.