年龄、焦虑与情节记忆之内容与来源的关系

将情节记忆区分为内容记忆和来源记忆,筛选年老和年轻的高、低特质焦虑者完成记忆任务,以探讨情节记忆年老化的选择性和变异性及其与焦虑之间的联系。两项实验结果表明来源记忆是否随增龄而有选择性受损受来源性质影响,与来源呈现方式和来源识记意识性无关。焦虑干扰了老年组的记忆操作,是老年人情节记忆存在个体差异的原因之一;但焦虑对青年组没有不利影响,提示焦虑调节两类记忆的年龄差异。     

Semantic and associative priming in picture naming

We report four picture-naming experiments in which the pictures were preceded by visually presented word primes. The primes could either be semantically related to the picture (e.g., "boat" - TRAIN: co-ordinate pairs) or associatively related (e.g., "nest" - BIRD: associated pairs). Performance under these conditions was always compared to performance under unrelated conditions (e.g., "flower" - CAT). In order to distinguish clearly the first two kinds of prime, we chose our materials so that (a) the words in the co-ordinate pairs were not verbally associated, and (b) the associate pairs were not co-ordinates. Results show that the two related conditions behaved in different ways depending on the stimulus-onset asynchrony (SOA) separating word and picture appearance, but not on how long the primes were presented. When presented with a brief SOA (114 ms, Experiment 1), the co-ordinate primes produced an interference effect, but the associated primes did not differ significantly from the unrelated primes. Conversely , with a longer SOA (234 ms, Experiment 2) the co-ordinate primes produced no effect, whereas a significant facilitation effect was observed for associated primes, independent of the duration of presentation of the primes. This difference is interpreted in the context of current models of speech production as an argument for the existence, at an automatic processing level, of two distinguishable kinds of meaning relatedness.     

Dysmorphic concern and behavioural impairment related to body image in adolescents

This study examined a moderated mediation model testing whether dysmorphic concern is related to behaviour altered to change appearance. This relationship is potentially mediated by depressive symptomatology (dysphoria and self-esteem) and ideas of reference about “laughing, commenting” and “attention, appearance,” and each mediated relationship moderated by sex. The sample was made up of 3377 adolescents from 12 to 18 years old (M_age = 14.52; SD = 1.65, 56.5% girls). The results showed that dysphoria and ideas of reference about “laughing, commenting” and “attention, appearance” partially mediated the relationship between dysmorphic concern and behavioural impairment related to body image. The relationship with dysphoria was moderated by sex, such that the mediation effect was stronger in girls than in boys. This result implies that girls who are worried about some characteristic of their appearance and show dysphoria are at greater risk of altered behaviour involving avoidance or controlling their appearance than boys. In addition, a possible risk of body dysmorphic disorder (3.45% of the sample) was found, with very prominent hiding behaviour using clothing or control behaviours, such as frequent weighing and looking at oneself in the mirror too much. Implications of these findings are discussed.     

Sexual differences in memory in shiny cowbirds

Avian brood parasites depend on other species, the hosts, to raise their offspring. During the breeding season, parasitic cowbirds (Molothrus sp.) search for potential host nests to which they return for laying a few days after first locating them. Parasitic cowbirds have a larger hippocampus/telencephalon volume than non-parasitic species; this volume is larger in the sex involved in nest searching (females) and it is also larger in the breeding than in the non-breeding season. In nature, female shiny cowbirds Molothrus bonariensis search for nests without the male’s assistance. Here we test whether, in association with these neuroanatomical and behavioural differences, shiny cowbirds display sexual differences in a memory task in the laboratory. We used a task consisting of finding food whose location was indicated either by the appearance or the location of a covering disk. Females learnt to retrieve food faster than males when food was associated with appearance cues, but we found no sexual differences when food was associated with a specific location. Our results are consistent with the view that parasitism and its neuroanatomical correlates affect performance in memory tasks, but the effects we found were not in the expected direction, emphasising that the nature of avian hippocampal function and its sexual differences are not yet understood. Received: 30 April 1998 / Accepted after revision: 5 September 1998     

Perceptual reasons

The two main theories of perceptual reasons in contemporary epistemology can be called Phenomenalism and Factualism. According to Phenomenalism, perceptual reasons are facts about experiences conceived of as phenomenal states, i.e., states individuated by phenomenal character, by what it’s like to be in them. According to Factualism, perceptual reasons are instead facts about the external objects perceived. The main problem with Factualism is that it struggles with bad cases: cases where perceived objects are not what they appear (illusions, broadly speaking) or where there is no perceived object at all (hallucinations). The main problem with Phenomenalism is that it struggles with good cases: cases where everything is perfectly normal and the external object is correctly perceived, so that one’s perceptual beliefs are knowledge. In this paper we show that there is a theory of perceptual reasons that avoids the problems for Factualism and Phenomenalism. We call this view Propositionalism. We use ‘proposition’ broadly to mean the entities that are contents of beliefs and other doxastic attitudes. The key to finding a middle ground between Phenomenalism and Factualism, we claim, is to allow our reasons to be false in bad cases. Despite being false, they are about the external world, not our phenomenal states.     

Continuous Response Monitoring of Relative Time-to-Contact Judgments: Does Effective Information Change During an Approach Event?

In many previous studies of time-to-contact (TTC) judgments of approaching objects, a response was measured after observers viewed the entire event and was used to infer the informational basis for the judgment. Such measures primarily reflect the information used at the end of the approach event and may not reveal whether observers used different information at different times during the event. Evidence indicates that observers use multiple information sources and that the effectiveness of information varies with distance. We introduce a method in which observers continuously report which of 2 approaching objects would reach them first, throughout the approach. We identified the occurrence and time of response reversals. Most observers changed their relative TTC judgments during the event. The pattern of responses indicated that observers did not use tau early during the approach when objects were far and did not use optical size later when the objects were closer. Most observers relied on either optical size or optical expansion rate early during the approach and expansion rate later during the event, although there were individual differences. A single relative TTC judgment measured after observers view an approach event may not reflect judgments or their informational basis throughout the entire event.