28 resultados para cognitive decline


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Italy is currently experiencing profound political change. One aspect of this change involves the decline in electoral support for the Italian Christian Democratic Party (DC) and the Italian Communist Party (PCI), now the Democratic Party of the Left (PDS). Signs of the electoral decline of both parties began to appear in the late 1970s and early 1980s and accelerated in the late 1980s and early 1990s. The pr imar y purpos e of th is thes is is to expla i n the electoral decline of the DC and PCI/PDS in the last decade. The central question being addressed in this thesis is the following: What factors contributed to the decline in electoral support for the DC and PCI? In addition, the thesis attempts to better comprehend the change in magni tude and direction of the Italian party system. The thesis examines the central question within an analytical framework that consists of models explaining electoral change in advanced industrial democracies and in Italy. A review of the literature on electoral change in Italy reveals three basic models: structural (socioeconomic and demographic factors), subcultural (the decline of the Catholic and Communist subcultures), and pol i tical (factors such as party strategy, and the crisis and collapse of communism in iv Eastern Europe and the former soviet Union and the end to the Cold War). Significant structural changes have occurred in Italy, but they do not invariably hurt or benefit either party. The Catholic and Communist subcultures have declined in size and strength, but only gradually. More importantly, the study discovers that the decline of communism and party strategy adversely affected the electoral performances of the DC and PC!. The basic conclusion is that political factors primarily and directly contributed to the decline in electoral support for both parties, while societal factors (structural and subcultural changes) played a secondary and indirect role. While societal factors do not contribute directly to the decline in electoral support for both parties, they do provide the context within which both parties operated. In addition, the Italian party system is becoming more fragmented and traditional political parties are losing electoral support to new political movements, such as the Lega Nord (LN-Northern League) and the Rete (Network). The growing importance of the North-South and centre-periphery cleavages suggests that the Italian party system, which is traditionally based on religious and ideological cleavages, may be changing.

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The present study examined individual differences in Absorption and fantasy, as well as in Achiievement and achievement striving as possible moderators of the perceptual closure effect found by Snodgrass and Feenan (1990). The study also examined whether different instructions (experiential versus instrumental) interact with the personality variables to moderate the relationship between priming and subsequent performance on a picture completion task. 1 28 participants completed two sessions, one to fill out the MPQ and NEO personality inventories and the other to complete the experimental task. The experimental task consisted of a priming phase and a test phase, with pictures presented on a computer screen for both phases. Participants were shown 30 pictures in the priming phase, and then shovm the 30 primed pictures along with 30 new pictures for the test phase. Participants were randomly assigned to receive one of the two different instruction sets for the task. Two measures of performance were calculated, most fragmented measure and threshold. Results of the present study confirm that a five-second exposure time is long enough to produce the perceptual closure effect. The analysis of the two-way interaction effects indicated a significant quadratic interaction of Absorption with priming level on threshold performance. The results were in the opposite direction of predictions. Possible explanations for the Absorption results include lack of optimal conditions, lack of intrinsic motivation and measurement problems. Primary analyses also revealed two significant between-subject effects of fantasy and achievement striving on performance collapsed across priming levels. These results suggest that fantasy has a beneficial effect on performance at test for pictures primed at all levels, whereas achievement striving seems to have an adverse effect on performance at test for pictures primed at all levels. Results of the secondary analyses with a revised threshold performance measure indicated a significant quadratic interaction of Absorption, condition and priming level. In the experiential condition, test performance, based on Absorption scores for pictures primed at level 4, showed a positive slope and performance for pictures primed at levels 1 and 7 based on Absorption showed a negative slope. The reverse effect was found in the instrumental condition. The results suggest that Absorption, in combination with experiential involvement, may affect implicit memory. A second significant result of the secondary analyses was a linear three-way interaction of Achievement, condition and priming level on performance. Results suggest that as Achievement scores increased, test performance improved for less fragmented primed pictures in the instrumental condition and test performance improved for more highly fragmented primes in the experiential condition. Results from the secondary analyses suggest that the revised threshold measure may be more sensitive to individual differences. Results of the exploratory analyses with Openness to Experience, Conscientiousness and agentic positive emotionality (PEM-A) measures indicated no significant effects of any of these personality variables. Results suggest that facets of the scales may be more useful with regard to perceptual research, and that future research should examine narrowly focused personality traits as opposed to broader constructs.

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Sleep spindles have been found to increase following an intense period of learning on a combination of motor tasks. It is not clear whether these changes are task specific, or a result of learning in general. The current study investigated changes in sleep spindles and spectral power following learning on cognitive procedural (C-PM), simple procedural (S-PM) or declarative (DM) learning tasks. It was hypothesized that S-PM learning would result in increases in Sigma power during Non-REM sleep, whereas C-PM and DM learning would not affect Sigma power. It was also hypothesized that DM learning would increase Theta power during REM sleep, whereas S-PM and C-PM learning would not affect Theta power. Thirty-six participants spent three consecutive nights in the sleep laboratory. Baseline polysomnographic recordings were collected on night 2. Participants were randomly assigned to one of four conditions: C-PM, S-PM, DM or control (C). Memory task training occurred on night 3 followed by polysomnographic recording. Re-testing on respective memory tasks occurred one-week following training. EEG was sampled at 256Hz from 16 sites during sleep. Artifact-free EEG from each sleep stage was submitted to power spectral analysis. The C-PM group made significantly fewer errors, the DM group recalled more, and the S-PM improved on performance from test to re-test. There was a significant night by group interaction for the duration of Stage 2 sleep. Independent t-tests revealed that the S-PM group had significantly more Stage 2 sleep on the test night than the C group. The C-PM and the DM group did not differ from controls in the duration of Stage 2 sleep on test night. There was no significant change in the duration of slow wave sleep (SWS) or REM sleep. Sleep spindle density (spindles/minute) increased significantly from baseline to test night following S-PM learning, but not for C-PM, DM or C groups. This is the first study to have shown that the same pattern of results was found for spindles in SWS. Low Sigma power (12-14Hz) increased significantly during SWS following S-PM learning but not for C-PM, DM or C groups. This effect was maximal at Cz, and the largest increase in Sigma power was at Oz. It was also found that Theta power increased significantly during REM sleep following DM learning, but not for S-PM, C-PM or C groups. This effect was maximal at Cz and the largest change in Theta power was observed at Cz. These findings are consistent with the previous research that simple procedural learning is consolidated during Stage 2 sleep, and provide additional data to suggest that sleep spindles across all non-REM stages and not just Stage 2 sleep may be a mechanism for brain plasticity. This study also provides the first evidence to suggest that Theta activity during REM sleep is involved in memory consolidation.

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Age-related differences in information processing have often been explained through deficits in older adults' ability to ignore irrelevant stimuli and suppress inappropriate responses through inhibitory control processes. Functional imaging work on young adults by Nelson and colleagues (2003) has indicated that inferior frontal and anterior cingulate cortex playa key role in resolving interference effects during a delay-to-match memory task. Specifically, inferior frontal cortex appeared to be recruited under conditions of context interference while the anterior cingulate was associated with interference resolution at the stage of response selection. Related work has shown that specific neural activities related to interference resolution are not preserved in older adults, supporting the notion of age-related declines in inhibitory control (Jonides et aI., 2000, West et aI., 2004b). In this study the time course and nature of these inhibition-related processes were investigated in young and old adults using high-density ERPs collected during a modified Sternberg task. Participants were presented with four target letters followed by a probe that either did or did not match one of the target letters held in working memory. Inhibitory processes were evoked by manipulating the nature of cognitive conflict in a particular trial. Conflict in working memory was elicited through the presentation of a probe letter in immediately previous target sets. Response-based conflict was produced by presenting a negative probe that had just been viewed as a positive probe on the previous trial. Younger adults displayed a larger orienting response (P3a and P3b) to positive probes relative to a non-target baseline. Older adults produced the orienting P3a and 3 P3b waveforms but their responses did not differentiate between target and non-target stimuli. This age-related change in response to targetness is discussed in terms of "early selection/late correction" models of cognitive ageing. Younger adults also showed a sensitivity in their N450 response to different levels of interference. Source analysis of the N450 responses to the conflict trials of younger adults indicated an initial dipole in inferior frontal cortex and a subsequent dipole in anterior cingulate cortex, suggesting that inferior prefrontal regions may recruit the anterior cingulate to exert cognitive control functions. Individual older adults did show some evidence of an N450 response to conflict; however, this response was attenuated by a co-occurring positive deflection in the N450 time window. It is suggested that this positivity may reflect a form of compensatory activity in older adults to adapt to their decline in inhibitory control.

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We examined the cognitive and emotional sequelae following mild head injury (MHI; e.g., concussion) in high-functioning individuals and whether persons with MHI pre~ent, both physiologically and via self-report, in a manner different from (i.e., underaroused) that of persons who have no history of head injury. We also investigated the effect arousal state ~as on the cognitive performance of this population. Using a quasiexperimental research design (N = 91), we examined changes in attention, working memory, and cognitive flexibility (subtests ofthe WAIS-III, 1997,WMS-III, 1997, & DKEFS, 2002) as a function of manipulated arousal (i.e., induced psychosocial stress/activation; reduced activation/relaxation). In addition to self-reported arousal and state anxiety (State-Trait Anxiety Inventory; Speilberger, 1983a) measures, physiological indices of arousal state (i.e., electrodermal responsivity, heart rate, and respiration activity) were recorded (via Polygraph Professional Suite, 2008) across a 2.5 hour interval while completing various cognitive tasks. Students also completed the Post-concussive Symptom Checklist (Gouvier et aI., 1992). The results demonstrate that university students who report a history ofMHI (i.e., "altered state of consciousness") experience significantly lower levels of anxiety, were physiologically underaroused, and were less responsive to stressors in their environment, compared to their non-~HI cohorts. As expected, cognitive flexibility (but not other neuropsychological measures of cognition) was advantaged with increased stress, and disadvantaged with reduced stress, in persons with reported MHI, but not for those without reported MHI which provided limited support for our hypothesis. Further, university students who had no complaints related to their previous MHI endorsed a greater number of traditional post-concussive symptoms in terms of intensity, duration and frequency as compared to students who did not report a MHI. The underarousal in traumatic brain injury has been associated with (ventromedial prefrontal cortex) VMPFC disruption and may be implicated in MHI generally. Students who report sustaining a previous MHI may be less able to physiologically respond and/or cognitively appraise, stressful experiences as compared to their no-MHI cohort and experience persistent, long-lasting consequences despite the subtle nature of a history of head injury.

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It is well established that postural threat modifies postural control, although little is known regarding the underlying mechanism(s) responsible. It is possible that changes in postural control under conditions of elevated postural threat result from alterations in cognitive strategies. The purpose of this study was to determine the influence of elevated postural threat on cognitive strategies and to determine the relationship between postural control, psychological, and cognitive measures. It was hypothesized that elevated postural threat would cause a shift to more conscious control of posture. It was also expected that a relationship between fear of falling and postural control would exist that could be explained by changes in conscious control of posture. Forty-eight healthy young adults stood on a force plate at two different surface heights: ground level (LOW) and 3.2m above ground level (HIGH). Center of pressure (COP) summary measures calculated to quantify postural control were the mean position (AP-COP MP), root mean square (AP-COP RMS) and mean power frequency (AP-COP MPF) in the anteriorposterior direction. Trunk sway measures calculated in the pitch direction were trunk angle and trunk velocity. Psychological measures including perceived balance confidence, perceived fear of falling, perceived anxiety, and perceived stability were self reported. As a physiological indicator of anxiety, electrodermal activity was collected. The cognitive strategies assessed were movement reinvestment and attention focus. A modified state-sp-ecific version of the Movement Specific Reinvestment Scale was used to measure conscious motor processing (CMP) and movement self-consciousness (MSC). An attention focus questionnaire was developed to assess the amount of attention directed to internal and external sources. An effect of postural threat on cognitive strategies was observed as participants reported more conscious control and a greater concern or worry about their posture at the HIGH postural threat condition as well as an increased internal and external focus of attention. In addition changes in postural control, psychological, and physiological measures were found. The participants leaned away from the edge of the platform, the frequency of their postural adjustments increased, and the velocity of their trunk movements increased. Participants felt less confident, more fearful, more anxious, and less stable with an accompanying increase in physiological anxiety. Significant correlations between perceived anxiety, AP-COP MP, and cognitive measures revealed a possible relationship that could be mediated by cognitive measures. It was found that with greater conscious motor processing, more movement self-consciousness, and a greater amount of attention focused externally there was a larger shift of the mean position away from the edge of the platform. This thesis provides evidence that postural threat can influence cognitive strategies causing a shift to more conscious control of movement which is associated with leaning away from the edge of the platform. Shifting the position of the body away from the direction of the postural threat may reflect a cognitive strategy to ensure safety in this situation due to the inability to employ a stepping strategy when standing on an elevated platform.

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The present research was designed to examine whether sex and/or emotional valence pl aya role in the cognitive consequences (e.g., memory) of expressive suppression. Seventy-two (36 male and 36 female) undergraduates were randomly assigned to either a control or expressive suppression condition, and were asked to watch silent film clips intended to elicit amusement and disgust. While watching each film, participants listened to sixteen nonemotional words. After each film, participants were asked to answer questions about wha t they had seen in the film (visual memory), to recall as many words as they could (auditory recall memory), and to select from a list any words that they had heard during the previous film clip (auditory recognition memory). With regard to the effects of expressive suppression on visual memory, results indicated a 3-way interaction between condition, sex and film emotion: Men performed more poorly than women on the visual memory test after watching both the amusing and disgusting films in the control condition, and when watching the amusing film in the expressive suppression condition. However, men in the expressive suppression condition performed better than women after watching the disgusting film. In terms of the effects of expressive suppression on auditory memory (recognition and recall), a condition x film emotion interaction indicated that there was no difference in auditory memory for the expressive suppression and control conditions when watching the amusing film, but that the expressive suppression group showed poorer auditory memory than the control group for words presented during the disgusting film. Moreover, a ma in effect of sex on auditory memory suggested that men recalled and recognized more words than women across conditions. Taken together, these findings suggest that both sex and the emotional valence of films may influence the effects of expressive suppression on memory. Results will be discussed in the context of previous literature concerning the effects of expressive suppression on cognition.

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Children with High-Functioning Autism (HF A) are more vulnerable to developing Obsessive Compulsive Disorder (OCD) than typically developing children and those with Low-Functioning Autism (Gadow et al., 2005). This study used a multiple baseline design across behaviours (Cooper, Heron, & Heward, 2007) to investigate if a two phase function-based Cognitive Behaviour Therapy (CBT) would decrease obsessive compulsive behaviours (OCBs) in two children ages 7 and 9 who met criteria for OCD and HF A. This multimodal treatment package consisted of treatment enhancements to meet the children's cognitive, linguistic, and social challenges associated with their HF A diagnosis, as well as a manual and accompanied children's workbook (Vause, Neil, & Feldman, in progress). In line with previous research conducted on CBT as a treatment for OCD in this population (e.g., Wood et at, 2009), the children in this study experienced clinically significant decreases in their OCBs as a result of receiving the CBT protocol.

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This study investigated improvements in parent knowledge of effective intervention strategies following participation in a group function-based CBT treatment (GFbCBT) package for children with comorbid OCD and ASD. Nineteen parents of children ages 7-12 years with High Functioning Autism (HFA) participated in the 9-week treatment program. Key components of treatment included psychoeducation and mapping, cognitive-behavioural skills training, function-based interventions and exposure and response prevention (ERP). Treatment sessions also included direct parent education, which followed a behavioural skills training model (Miltenberger, 2008). Parent knowledge (N = 19) was measured pre and post treatment using a vignette about a child demonstrating obsessive-compulsive behaviour. Results of a one-tailed pairwise t-test indicated statistically significant changes (p=.036) in overall parent knowledge following participation in treatment. Statistically significant changes were also found in parents’ ability to generate ERP and function-based intervention strategies. These results provide preliminary evidence that parents benefit from active involvement in the GFbCBT treatment package.

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Accuracy at reporting a second-target (T2) is reduced if it is presented within approximately 500 ms of the first target (T1) – an attentional blink (AB). Early models explained the AB in terms of attentional limitations creating a processing bottleneck such that T2 processing would be impaired while T1 processing was ongoing. Theoretical models of the AB have more recently been expanded to include the role of cognitive control. In this dissertation I propose that cognitive control, defined as the optimization of information processing in order to achieve goals, is maladapted to the dual-task conditions of the AB task in that cognitive control optimizes the T1 goal, due to its temporal proximity, at the cost of T2. I start with the concept that the role of cognitive control is to serve goals, and that how goals are conceived of and the degree of motivation associated with those goals will determine whether cognitive control will create the condition that cause the AB. This leads to the hypothesis that electrophysiological measures of cognitive control and the degree of attentional investment resulting from cognitive control modulate the AB and explain individual differences in the AB. In a series of four studies feedback-related N2 amplitude, (reflecting individual differences in the strength of cognitive control), and event-related and resting alpha frequency oscillatory activity (reflecting degree of attentional investment), are used to explain both intra- and inter-individual variability in performance on the AB task. Results supported the hypothesis that stronger cognitive control and greater attentional investment are associated with larger AB magnitudes. Attentional investment, as measured by alpha frequency oscillations, and cognitive control, as measured by the feedback-related N2, did not relate to each other as hypothesized. It is proposed that instead of a measure of attentional investment alone, alpha frequency oscillatory activity actually reflects control over information processing over time, in other words the timing of attention. With this conceptualization, various aspects of cognitive control, either related to the management of goals (feedback-related N2) or the management of attention over time to meet goals, explain variability in the AB.

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Behavioral researchers commonly use single subject designs to evaluate the effects of a given treatment. Several different methods of data analysis are used, each with their own set of methodological strengths and limitations. Visual inspection is commonly used as a method of analyzing data which assesses the variability, level, and trend both within and between conditions (Cooper, Heron, & Heward, 2007). In an attempt to quantify treatment outcomes, researchers developed two methods for analysing data called Percentage of Non-overlapping Data Points (PND) and Percentage of Data Points Exceeding the Median (PEM). The purpose of the present study is to compare and contrast the use of Hierarchical Linear Modelling (HLM), PND and PEM in single subject research. The present study used 39 behaviours, across 17 participants to compare treatment outcomes of a group cognitive behavioural therapy program, using PND, PEM, and HLM on three response classes of Obsessive Compulsive Behaviour in children with Autism Spectrum Disorder. Findings suggest that PEM and HLM complement each other and both add invaluable information to the overall treatment results. Future research should consider using both PEM and HLM when analysing single subject designs, specifically grouped data with variability.

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Cognitive interviews were used to evaluate two draft versions of a financial survey in Jamaica. The qualitative version used a few open-ended questions, and the quantitative version used numerous close-ended questions. A secondary analysis based on the cognitive interview literature was used to guide a content analysis of the aggregate data of both surveys. The cognitive interview analysis found that the long survey had fewer respondent errors than the open-ended questions on the short survey. A grounded theory analysis then examined the aggregate cognitive data, showing that the respondents attached complex meanings to their financial information. The main limitation of this study was that the standard assessments of quantitative and qualitative reliability and validity were not utilized. Further research should utilize statistical methods to compare and contrast aggregated cognitive interview probe responses on open and close ended surveys.

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Abstract The therapeutic alliance (TA) is the most studied process of adult psychotherapeutic change (Zack et al., 2007) and has been found to have a moderate but robust relationship with therapeutic outcome regardless of treatment modality (Horvath, 2001). The TA is loosely described as the extent to which the therapist and the participant connect emotionally and work together towards goals. Conceptualizations of the TA with children have relied on adult models, even though it is widely acknowledged that the pediatric population will rarely willingly commit to therapy, nor readily admit to any challenges that they may be experiencing (Keeley, Geffken, McNamara & Storch, 2011). For children with Autism Spectrum Disorder (ASD) the therapeutic alliance may require an even greater retheorizing considering the communicative and social difficulties of this particular population. Despite this need, research on children with ASD and the therapeutic TA is almost non-existent. In this qualitative study, transcripts from semi-structured interviews with mothers of children with ASD were analyzed using Interpretative Phenomenological Analysis (IPA). IPA closely examines how individual people make sense of their life experiences using a theme-by-theme approach. The three interviewees were mothers whose children were participants in a nine-week Cognitive Behaviour Therapy (CBT) group for obsessive-compulsive behaviours (OCB). A total of four superordinate themes were identified: (i) Centralization and disremembering the TA, (ii) Qualities of the therapist, (iii) TA and the importance of time, and (iv) Signs of a healthy TA. The mothers’ perspectives on the TA suggest that, for them and their children, a strong TA was a required component of the therapy. Implications for clinicians and researchers are discussed.