Visual Imagery Processing and Knowledge of Famous Names in Alzheimer's Disease and MCI

ABSTRACT

The study of memory for famous people and visual imagery retrieval was investigated in patients in the early stages of Alzheimer's disease (AD) and in the prodromal stage of AD, so-called Mild Cognitive Impairment (MCI). Fifteen patients with AD (MMSE ≥23), 15 patients with amnestic MCI (a-MCI) and 15 normal controls (NC) performed a famous names test designed to evaluate the semantic and distinctive physical features knowledge of famous persons. Results indicated that patients with AD and a-MCI generated significantly less physical features and semantic biographical knowledge about famous persons than did normal control participants. Additionally, significant differences were observed between a-MCI and AD patients in all tasks. The present findings confirm recent studies reporting semantic memory impairment in MCI. Moreover, the current findings show that mental imagery is lowered in a-MCI and AD and is likely related to the early semantic impairment.     

Affective Priming Effects in the Left and Right Cerebral Hemispheres in Patients With Alzheimer's Disease

Alzheimer’s disease (AD) patients and control subjects were tested in an affective priming paradigm associated with an affective discrimination task. Two pictures, one affectively positive or affectively negative and the other neutral, were presented simultaneously in the right and in the left visual fields; the participants had to decide which of the two pictures was the most affectively positive or negative. The target pictures were preceded by a prime picture that was either affectively positive, affectively negative, or neutral. The principal result was the observation, in AD patients as well as in control subjects, of negative affective priming effects for targets presented in the right hemisphere, and of positive affective priming effects for targets presented in the left hemisphere. The presence of affective priming effects suggests that AD patients have no particular deficit in the automatic activation of emotional information; the fact that priming effects were also observed for targets presented in the left hemisphere showed that AD patients probably have no left hemisphere deficit in the automatic activation of emotional information. However, in AD patients, affective priming effects were significant with negative targets but not with positive targets, which could suggest that AD patients processed positive targets in a more semantic way than negative targets.     

Lexical-semantic body knowledge in 5- to 11-year-old children: How spatial body representation influences body semantics

This study addresses the relation between lexico-semantic body knowledge (i.e., body semantics) and spatial body representation (i.e., structural body representation) by analyzing naming performances as a function of body structural topography. One hundred and forty-one children ranging from 5 years 2 months to 10 years 5 months old were asked to provide a lexical label for isolated body part pictures. We compared the children’s naming performances according to the location of the body parts (body parts vs. head features and also upper vs. lower limbs) or to their involvement in motor skills (distal segments, joints, and broader body parts). The results showed that the children’s naming performance was better for facial body parts than for other body parts. Furthermore, it was found that the naming of body parts was better for body parts related to action. These findings suggest that the development of a spatial body representation shapes the elaboration of semantic body representation processing. Moreover, this influence was not limited to younger children. In our discussion of these results, we focus on the important role of action in the development of body representations and semantic organization.     

‘Beauty is in the eye of the beer holder’: People who think they are drunk also think they are attractive

This research examines the role of alcohol consumption on self‐perceived attractiveness. Study 1, carried out in a barroom (N= 19), showed that the more alcoholic drinks customers consumed, the more attractive they thought they were. In Study 2, 94 non‐student participants in a bogus taste‐test study were given either an alcoholic beverage (target BAL [blood alcohol level]= 0.10 g/100 ml) or a non‐alcoholic beverage, with half of each group believing they had consumed alcohol and half believing they had not (balanced placebo design). After consuming beverages, they delivered a speech and rated how attractive, bright, original, and funny they thought they were. The speeches were videotaped and rated by 22 independent judges. Results showed that participants who thought they had consumed alcohol gave themselves more positive self‐evaluations. However, ratings from independent judges showed that this boost in self‐evaluation was unrelated to actual performance.     

The more you play,the more aggressive you become: A long-term experimental study of cumulative violent video game effects on hostile expectations and aggressive behavior

It is well established that violent video games increase aggression. There is a stronger evidence of short-term violent video game effects than of long-term effects. The present experiment tests the cumulative long-term effects of violent video games on hostile expectations and aggressive behavior over three consecutive days. Participants (N = 70) played violent or nonviolent video games 20 min a day for three consecutive days. After gameplay, participants could blast a confederate with loud unpleasant noise through headphones (the aggression measure). As a potential causal mechanism, we measured hostile expectations. Participants read ambiguous story stems about potential interpersonal conflicts, and listed what they thought the main characters would do or say, think, and feel as the story continued. As expected, aggressive behavior and hostile expectations increased over days for violent game players, but not for nonviolent video game players, and the increase in aggressive behavior was partially due to hostile expectations.     

When collective memories of victimhood fade: Generational evolution of intergroup attitudes and political aspirations in Belgium

Collective memory theories propose that groups' remembrances of their past depend upon their current social situation. In Belgium, a significant proportion of Dutch speakers share a collective memory of past victimisation by French speakers and fight for an ever‐larger autonomy of their region. Yet, as the respective economic, political and social situations of the linguistic regions of Belgium recently evolved with a reversal of fortunes, the current experience of younger Dutch speakers does not fit the traditional memory anymore. We thus predicted that the collective memories of victimhood would decline amongst them, thus bringing changes in intergroup attitudes and political aspirations. Three generations were compared in a survey of 1226 French‐speaking and 1457 Dutch‐speaking individuals. For both groups, younger generations evidenced less regionalist and more integrative positions than older ones. However, these effects were stronger for Dutch‐speaking respondents, and for them, collective memory of victimhood mediated the relation linking age and identification with Belgium, intergroup attitudes and political aspirations. We concluded that the current social context has decisive consequences for collective remembrances, which, in turn, impact intergroup relations and political attitudes and choices.     

Does visual experience influence the spatial distribution of auditory attention?

Sighted individuals are less accurate and slower to localize sounds coming from the peripheral space than sounds coming from the frontal space. This specific bias in favour of the frontal auditory space seems reduced in early blind individuals, who are particularly better than sighted individuals at localizing sounds coming from the peripheral space. Currently, it is not clear to what extent this bias in the auditory space is a general phenomenon or if it applies only to spatial processing (i.e. sound localization). In our approach we compared the performance of early blind participants with that of sighted subjects during a frequency discrimination task with sounds originating either from frontal or peripheral locations. Results showed that early blind participants discriminated faster than sighted subjects both peripheral and frontal sounds. In addition, sighted subjects were faster at discriminating frontal sounds than peripheral ones, whereas early blind participants showed equal discrimination speed for frontal and peripheral sounds. We conclude that the spatial bias observed in sighted subjects reflects an unbalance in the spatial distribution of auditory attention resources that is induced by visual experience.     

Distal rhythm influences whether or not listeners hear a word in continuous speech: Support for a perceptual grouping hypothesis

Due to extensive variability in the phonetic realizations of words, there may be few or no proximal spectro-temporal cues that identify a word’s onset or even its presence. Dilley and Pitt (2010) showed that the rate of context speech, distal from a to-be-recognized word, can have a sizeable effect on whether or not a word is perceived. This investigation considered whether there is a distinct role for distal rhythm in the disappearing word effect. Listeners heard sentences that had a grammatical interpretation with or without a critical function word (FW) and transcribed what they heard (e.g., are in Jill got quite mad when she heard there are birds can be removed and Jill got quite mad when she heard their birds is still grammatical). Consistent with a perceptual grouping hypothesis, participants were more likely to report critical FWs when distal rhythm (repeating ternary or binary pitch patterns) matched the rhythm in the FW-containing region than when it did not. Notably, effects of distal rhythm and distal rate were additive. Results demonstrate a novel effect of distal rhythm on the amount of lexical material listeners hear, highlighting the importance of distal timing information and providing new constraints for models of spoken word recognition.     

Enriched housing reverses age-associated impairment of cognitive functions and tPA-dependent maturation of BDNF

Although tissue type plasminogen activator (tPA) and brain derived neurotrophic factor (BDNF) have been extensively described to influence brain outcomes in a number of disorders, their roles during physiological aging are poorly investigated. In the present study, we investigated whether maintenance of mice in different environmental conditions could influence age-associated changes in hippocampal tPA expression and BDNF maturation in relation with modifications of their cognitive performances. Our data indicate that maintenance in enriched housing led to a reversal of age-associated decrease in expression of hippocampal tPA. A subsequent increase in the level of mature BDNF and an improvement in emotional and spatial memories were observed. Taken together, these data suggest that the tPA–BDNF axis could play a critical role in the control of cognitive functions influenced both by the age and housing conditions.