Subjective organization in the episodic memory of individuals with Parkinson’s disease associated with mild cognitive impairment

Word clustering (i.e., the ability to reproduce the same word pairs in consecutive recall trials of an unrelated word list) has been extensively investigated as a proxy of subjective organization (SO) of memorandum. In healthy subjects and in groups of brain-damaged patients, the rate of SO generally predicts accuracy of word list recall. This study aimed at evaluating SO in the performance of patients with Parkinson’s disease (PD) on a word list recall task in order to investigate the basic mechanisms of episodic memory impairment that are frequently observed in these patients. For this purpose, 56 PD patients, who were stratified according to the presence and quality of mild cognitive impairment (MCI), and a group of healthy controls (HCs) were administered a word list task and an extensive battery of neuropsychological tests. Results showed that recall accuracy on the word list task progressively decreased passing from HC to PD patients without cognitive impairment, to patients with single-domain dysexecutive MCI and to patients with multiple-domain dysexecutive and amnesic MCI. Conversely, only the latter PD group showed a lower SO score than that achieved by the other groups. In the overall PD group, correlational and regression analyses demonstrated that SO scores and a composite score of executive functions were not reciprocally related, but both provided an independent and significant contribution to the prediction of word list recall accuracy. These data are discussed in terms of the contribution of executive functions and hippocampal storage processes to the onset of memory impairment in PD.     

Grandparent-grandchild contact and attitudes toward older adults: moderator and mediator effects

Two studies tested the intergroup contact hypothesis in the context of the grandparent-grandchild relationship. The hypothesis suggests that contact with an out-group member has more influence on attitudes toward the out-group when group memberships are salient. In Study 1, the predicted link was found but only for grandparents with whom the grandchild had more frequent contact. The second study examined only the most frequent grandparent relationship and replicated the effect. This study also investigated the role of various mediators of the link between quality of contact and attitudes, as well as quality of contact and perceived out-group variability. Perspective taking, anxiety, and accommodation mediated the effects of contact on attitudes, whereas individuation and self-disclosure mediated the effects of contact on perceived out-group variability. Moderated mediational analysis indicated that the moderating effect of group salience occurs between quality of contact and the mediator, not between the mediator and attitudes.     

A study on the role of the dorsal striatum and the nucleus accumbens in allocentric and egocentric spatial memory consolidation

There is now accumulating evidence that the striatal complex in its two major components, the dorsal striatum and the nucleus accumbens, contributes to spatial memory. However, the possibility that different striatal subregions might modulate specific aspects of spatial navigation has not been completely elucidated. Therefore, in this study, two different learning procedures were used to determine whether the two striatal components could be distinguished on the basis of their involvement in spatial learning using different frames of reference: allocentric and egocentric. The task used involved the detection of a spatial change in the configuration of four objects placed in an arena, after the mice had had the opportunity to experience the objects in a constant position for three previous sessions. In the first part of the study we investigated whether changes in the place where the animals were introduced into the arena during habituation and testing could induce a preferential use of an egocentric or an allocentric frame of reference. In the second part of the study we performed focal injections of the N-methyl-d-aspartate (NMDA) receptors' antagonist, AP-5, within the two subregions immediately after training. The results indicate that using the two behavioral procedures, the animals rely on an egocentric and an allocentric spatial frame of reference. Furthermore, they demonstrate that AP-5 (37.5, 75, and 150 ng/side) injections into the dorsal striatum selectively impaired consolidation of spatial information in the egocentric but not in the allocentric procedure. Intra-accumbens AP-5 administration, instead, impaired animals trained using both procedures.     

Self-defeating personality and memories of parents' child-rearing behavior: a replication

A recent study of correlations of self-defeating personality and memories of parents' child-rearing behaviour has been replicated on a larger sample. Non-clinical volunteers (145 women and 114 men) were administered Schill's Self-defeating Personality Scale and a short version of the EMBU-Egna Minnen Betr?ffande Uppfostran (own memories of parental education) scale. Replicating previous findings, memories of rejecting or nonsupportive parents were significantly correlated with scores for the Self-defeating Personality Scale for both women (rejecting mother, r = 24; supportive mother, r = -.29; rejecting father, r = .23; supportive father, r = -.36) and men (rejecting mother, r = 40; rejecting father, r = .41; supportive father, r = -.28). Memories of an overinvolved parent were significantly correlated with self-defeating personality scores only among men (mother: r = .41; father: r = .36) as in the original study.     

Discriminative game-related statistics between basketball starters and nonstarters when related to team quality and game outcome

The aim of the present paper was to examine the differences in game-related statistics between basketball players who are selected for the starting five of the team (starters) and those who are not (nonstarters) when related to game outcome (winning and losing) and team quality (best teams, teams classified for the playoffs; and worst teams, teams who miss playoff classification). Archival data were gathered for all 2002-2003 regular season games from the Portuguese Professional League (N = 156). Discriminant analysis was used to identify the game-related statistics that differentiate between starters and nonstarters and interpreted by the examination of the structure coefficients (SC). When the best teams won the games, results described differences between starters and nonstarters with an emphasis on defensive rebounds (SC = .32), assists (SC = .32) and committed fouls (SC = -.68). When the worst teams won the games, results described differences between starters and nonstarters with an emphasis on 2-point field goals successful (SC = .47) and unsuccessful (SC = .48), defensive rebounds (SC =.39), successful free throws (SC =.32), and committed fouls (SC = -.55). An also important finding was that, in best teams, the nonstarters' performance was worse in the games that the team lost, whereas in worst teams, it was the starters' performance that was worse in the games that the team lost.     

Contents of Volume 20

Volume Contents

Contents of Volume 20     

Clinicians' ratings and self-reports of basic symptoms

A sample of 34 paranoid or undifferentiated schizophrenic outpatients were given the Rome Basic Disorders Scale, a self-rating questionnaire aimed to the assessment of basic symptoms, as defined by the Bonn Scale. These patients were then interviewed on the same 54 basic symptoms explored with the scale, by two independent clinicians blind to the outpatients' data. Self-ratings compared with clinicians' ratings by Student t for dependent samples yielded only one significant difference (p< .01) for the item measuring hypersensitivity to light. Present findings suggest that the Rome Basic Disorders Scale may be safely self-rated even by collaborative schizophrenic patients.     

Time course of brain activation during graphemic/phonologic processing in reading: an ERP study

The present study sought to investigate the time course of brain activation during grapheme-to-phoneme conversion and phonologic processing of legal Italian syllables. To this goal, we monitored a group of right-handed native Italian volunteers performing a phonologic decision task (same/different judgments). ERPs were recorded from 28 scalp sites during silent reading. Analysis of ERP latency showed faster responses to same syllables than to different ones as early as 105 ms at left temporal electrode site and 160 ms at frontal sites. The first effect of phonologic/graphemic incongruity on the amplitude of ERPs was observed at lateral occipital/posterior temporal sites (N185), where physiologic responses were enhanced to incongruous syllables.     

Spontaneous attention to word content versus emotional tone: differences among three cultures

A Stroop interference task was used to test the hypothesis that people in different cultures are differentially attuned to verbal content vis-à-vis vocal tone in comprehending emotional words. In Study 1, Americans showed greater difficulty ignoring verbal content than ignoring vocal tone (which reveals an attentional bias for verbal content); but Japanese showed greater difficulty ignoring vocal tone than ignoring verbal content (which reveals a bias for vocal tone). In Study 2, Tagalog-English bilinguals in the Philippines showed an attentional bias for vocal tone regardless of the language used, suggesting that the effect is largely cultural rather than linguistic. Implications for culture-and-cognition research are discussed.     

Differential involvement of NMDA and AMPA receptors within the nucleus accumbens in consolidation of information necessary for place navigation and guidance strategy of mice

Recent evidence now points to a role of glutamate transmission within the nucleus accumbens (Nacc) in spatial learning and memory. Unfortunately, the role of the distinct classes of glutamate receptors within this structure in mediating the different steps of the memorization process is not clear. The aim of this study therefore was to further investigate this issue, trying to assess the involvement of the two classes of glutamate receptors within the Nacc in consolidation of spatial information using an associative spatial task, the water maze. For this purpose, focal injections of the NMDA antagonist, AP-5, and of the AMPA antagonist, DNQX, have been performed immediately after the training phase, and mice have been tested for retention 24 h later. Two different versions of the water-maze task have been used: In the place version, animals could learn the position of the platform using visual distal cues, and in the cue version, the location of the platform was indicated by a single proximal cue. The results demonstrated that posttraining NMDA receptor blockade affects mice response in the place but not in the cue water-maze task. On the contrary, AMPA receptor blockade induced no effect in either version of the task. These data confirm a functional dissociation between glutamate receptors located in the Nacc in modulating spatial memory consolidation and indicate that they are specifically involved in consolidation of information necessary to acquire a place but not to a guidance strategy.