Asymmetric Switch Cost and Backward Inhibition: Carryover Activation and Inhibition in Switching Between Tasks of Unequal Difficulty

Asymmetric switch cost, observed when switching between tasks varying in difficulty, shows that the difference between repeat and switch trials is greater when switching to the easier task. Early explanations of this effect attributed this pattern to both positive priming of the difficult task and negative priming of the easier task, but more recent models have focused only on activation processes. The role of inhibition in asymmetric switch cost was examined using backward inhibition, a more...

Attention During Adaptation Weakens Negative Afterimages of Perceptually Colour-Spread Surfaces

The visual system can complete coloured surfaces from stimulus fragments, inducing the subjective perception of a colour-spread figure. Negative afterimages of these induced colours were first reported by S. Shimojo, Y. Kamitani, and S. Nishida (2001). Two experiments were conducted to examine the effect of attention on the duration of these afterimages. The results showed that shifting attention to the colour-spread figure during the adaptation phase weakened the subsequent afterimage. On th...

Stimulus-Response Compatibilities During Top-Bottom Discriminations

Participants indicated whether a small dot was located near the top or bottom pole of a rotated object. Response times increased as a function of object orientation more for top trials than for bottom trials. The interaction between orientation and response was shown to be due to a relationship between response times and the dot's height on the screen. The orientation effect was influenced, positively and negatively, by a vertical arrangement of the response keys depending on whether the uppe...

Word-Learning Performance in Beginning Readers

This investigation examined word-learning performance in beginning readers. The children learned to read words with regular spelling-sound mappings (e.g., snake) more easily than words with irregular spelling-sound mappings (e.g., sword). In addition, there was an effect of semantics: Children learned to read concrete words (e.g., elbow) more successfully than abstract words (e.g., temper). Trial-by-trial learning indicated that children made greater use of the regularity and semantic propert...

Masked Repetition Priming and Proportion Effects Under Cognitive Load

The authors used a cognitive load manipulation (rehearsing a string of digits during the trial) to test the automaticity of (a) masked repetition priming and (b) the masked repetition proportion (RP) effect (i.e., greater priming when the proportion of repetition-prime trials is higher) in the lexical decision task. The RP (.2 vs. .8) was varied across blocks. Masked priming was not reduced under load compared with a no-load group. Surprisingly, only the load group showed an RP effect in resp...

Implications Des Processus d'Imagerie Mentale Dans Le Déficit Du Codage Imagé Des Informations Verbales Au Cours Du Vieillissement Normal

L'étude que nous proposons vise par conséquent à éclairer les résultats divergents des études déjà effectuées sur le vieillissement du codage imagé en proposant l'hypothèse selon laquelle ce vieillissement du codage imagé des mots concrets en mémoire nécessiterait d'être mis en rapport avec l'altération liée à l'âge des processus d'imagerie mentale, notamment ceux liés à la génération et au maintien d'images mentales.\n Ce résultat s'accorde avec l'hypothèse de Salthouse (1985a, 1985b, 1996) ...

Motor Maps, Seizures, and Behaviour

Atypically organised motor maps have been described in some people with epilepsy and we have modelled this in rats. Our goal is to more fully understand the mechanisms responsible for seizure-induced functional brain reorganisation and to reverse their effects. Here we present an overview of the relationship between neocortical motor maps, seizures, and interictal behaviour. To begin we summarise the observations of atypical motor maps with epilepsy and in animal models following experimental...