ABSTRACT NEGATIVE REMEMBERING SEPTEMBER 2007 AYCAN KAPUCU, B.A., BOGAZICI UNIVERSITY ISTANBUL M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Caren M. Rotello Three experiments investigated the use of recall-to-accept and recall-to-reject processes in recognition and remember-know decisions. In all three experiments, participants studied a mixed list of singular and plural words. During the recognition test, participants made old-new confidence ratings and remember-know judgments for studied items, lures that were similar to studied items, and new lures. Old-similar ROC curves were constructed from the confidence ratings and found to be linear, consistent with the use of a high-threshold recollective process. The ROC intercepts and remember response rates converged on the same estimates of the amount of recollection for both positive (recall-to-accept) and negative (recall-to-reject) decisions.

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Yes / Phencyclidine (PCP) produces cognitive deficits of relevance to schizophrenia in animal models. The aim was to investigate the efficacy of the D1-like receptor agonist, SKF-38393, to improve PCPinduced deficits in the novel object recognition (NOR) and operant reversal learning (RL) tasks. Rats received either sub-chronic PCP (2 mg/kg) or vehicle for 7 days, followed by a 7-day washout. Rats were either tested in NOR or the RL tasks. In NOR, vehicle rats successfully discriminated between novel and familiar objects, an effect abolished in PCP-treated rats. SKF-38393 (6 mg/kg) significantly ameliorated the PCP-induced deficit (Pb0.01) an effect significantly antagonised by SCH-23390 (0.05 mg/kg), a D1-like receptor antagonist (Pb0.01). In the RL task sub-chronic PCP significantly reduced performance in the reversal phase (Pb0.001); SKF-38393 (6.0 mg/kg) improved this PCPinduced deficit, an effect antagonised by SCH-23390 (Pb0.05). These results suggest a role for D1-like receptors in improvement of cognitive function in paradigms of relevance to schizophrenia.

Low-frequency (LF) words have higher hit rates (HRs) and lower false alarm rates (FARs) than high-frequency (HF) words in recognition memory, a phenomenon termed the mirror effect by Glanzer and Adams (1985). The primary mechanism for producing the mirror effect varies substantially across models of recognition memory, with some models localizing the effects during encoding and others during retrieval. The current experiments contrast two retrieval-stage models, the Source of Activation Confusion (SAC; Reder, Nhouyvanisvong, Schunn, Ayers, Angstadt, & Hiraki, 2000) model and the unequal variance signal detection theory (UVSDT) criterion shift model (e.g., DeCarlo, 2002). The SAC model proposes that two distinct processes underlie the HR and FAR effects, with a familiarity process driving the FAR effect and a recollective process driving the HR effect. The UVSDT criterion shift model assumes that subjects use different criteria when making recognition judgments for HF and LF words, with this single process driving both the HR and FAR effects. Experiment 1 incorporated divided attention and speeded responding manipulations designed to remove the contribution of recollection in the SAC model, thereby eliminating the LF HR advantage. Experiment 2 manipulated the salience of the frequency classes, as the UVSDT criterion shift model requires that subjects are aware of the distinct frequency classes in order to shift their criteria. Across both experiments, model simulations and direct fits of the SAC model demonstrated systematic errors in prediction. While the UVSDT model struggled in fits to Experiment 1 data, the model provided acceptable fits to Experiment 2 data and accurately predicted the general pattern of effects in all cases. Furthermore, state-trace analyses provided compelling evidence in favor of single-process rather than dual-process models of recognition memory, casting serious doubt on the validity of the dual-process SAC model. Finally, the current experiments highlight the importance of obtaining model-based estimates of sensitivity and bias across frequency classes, as the standard practice of conducting direct comparisons of HRs and FARs for HF and LF words confounds bias and sensitivity differences.

no / Significant changes in endogenous plasma hormone levels are required to sustain pregnancy which provides a unique opportunity to study their effect on cognitive function. Four carefully selected tests from the Cambridge Neuropsychological Automated Test Battery (CANTAB) were administered to assess the cognitive function of a group of 23 women during each trimester of pregnancy and at three months following birth. Test scores were compared with a control group of 24 non-pregnant women. The Edinburgh Postnatal Depression Scale was administered to assess anxiety and risk of depression. The National Adult Reading Test (NART) was used as a measure of verbal intelligence. Plasma hormone levels were measured at each time-point. The pregnant group scored significantly lower than the control group on the Spatial Recognition Memory (SRM) test at the second trimester and postpartum assessments (p ⩽ 0.004). A significant pregnant group-time interaction (p = 0.005) for SRM performance was demonstrated. Compared to their first trimester assessment, the pregnant group scored on average 11.7% less on each subsequent SRM test. The pregnant group reported more symptoms of anxiety and depression compared to the control group (EPDS-4 point increase in mean score at each assessment, p = 0.002). There were no plasma hormone levels and test score associations identified.

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Yes / Memory performance is usually impaired when participants have to encode information while performing a concurrent task. Recent studies using recall tasks have found that emotional items are more resistant to such cognitive depletion effects than non-emotional items. However, when recognition tasks are used, the same effect is more elusive as recent recognition studies have obtained contradictory results. In two experiments, we provide evidence that negative emotional content can reliably reduce the effects of cognitive depletion on recognition memory only if stimuli with high levels of emotional intensity are used. In particular, we found that recognition performance for realistic pictures was impaired by a secondary 3- back working memory task during encoding if stimuli were emotionally neutral or had moderate levels of negative emotionality. In contrast, when negative pictures with high levels of emotional intensity were used, the detrimental effects of the secondary task were significantly attenuated. / UK Biotechnology and Biological Sciences Research Council (BBSRC, reference: BB/H001476/1, and BB/H001476/2)

Introdução: O etilismo é uma doença crônica e progressiva que tem um impacto significante nos valores sociais e econômicos da sociedade. A interrupção abrupta do consumo crônico de etanol pode levar à Síndrome de Abstinência alcoólica (SAA) com repercussões na saúde do indivíduo. Atualmente, muita atenção também tem sido dada ao consumo espaçado de etanol em doses elevadas, caracterizado como binge. Dentre as várias consequências do consumo agudo e/ou crônico do etanol, podem-se destacar os déficits em teste de aprendizagem e de memória. Objetivos: verificar se a abstinência ao etanol após o consumo involuntário ou semivoluntário de etanol (crônico ou agudo) é capaz de interferir na aprendizagem, na memória e na ansiedade de ratos adultos. Materiais e Métodos: Foram utilizados 196 ratos albinos, Wistar e machos, com 21 dias de vida. Inicialmente os animais foram divididos em dois grandes grupos para compor o Estudo 1 ou o estudo 2. No estudo 1 a via de administração foi semivoluntária (etanol a 6%) e no estudo 2 foi involuntária (por gavagem intragástrica- 1g etanol/kg). Em ambos os estudos os animais foram divididos novamente em relação ao tipo de bebida que receberiam (água ou etanol) e tempo de consumo (agudo- 2 horas ou crônico- 21 dias, sendo que no estudo 2 a ingestão etílica aconteceu a cada 3 dias). No 23º dia (após 48 horas da última ingestão etílica) os animais foram testados no Teste de Memória de Reconhecimento (TMR), no Labirinto em Cruz Elevado (LCE) e no Labirinto Aquático de Morris (LAM) por dois dias consecutivos e retestados após 28 dias. Resultados: No estudo 1 os resultados indicaram que a abstinência ao etanol após o consumo agudo ou crônico de etanol não foi capaz de alterar a aprendizagem e a memória espacial no LAM, porém prejuízos na memória espacial de longo prazo foram observados nos animais submetidos ao consumo agudo de etanol. Não foram observadas alterações na Memória de Reconhecimento na Sessão treino e na Memória de Reconhecimento de Curto Prazo, porém a exposição aguda ao etanol foi capaz de gerar prejuízos na memória de Reconhecimento de Longo Prazo. Não houve diferenças nos níveis de ansiedade dos animais do estudo. Em relação ao estudo 2, foi possível observar que a abstinência do etanol após o consumo agudo foi capaz de gerar um prejuízo na memória espacial de curto prazo e que o consumo crônico e agudo de etanol não foram capaz de prejudicar a Memória de Reconhecimento dos animais estudados. Ainda que, os animais expostos ao consumo agudo e crônico de etanol, em abstinência ao etanol de 48 horas apresentaram níveis de ansiedade elevados. Conclusão: O etanol influencia de forma diferente a memória espacial, a memória de reconhecimento e os níveis de ansiedade a depender da via de administração (e, portanto da quantidade de etanol ingerida) e do tempo de consumo. / Introduction: Alcoholism is a chronic and progressive disease that has a significant impact on social and economic values of society. Abrupt withdrawal of chronic ethanol consumption can lead to alcohol withdrawal syndrome (AWS) which impacts on the health of the individual. Currently, much attention has also been attributed to the spaced ethanol consumption in high doses, characterized as \"binge\". Among the many consequences of acute and/or chronic consumption ethanol, can highlight the deficits in learning and memory test. Objectives: verify if abstinence to ethanol after the involuntary consumption of ethanol or semi-voluntary (chronic or acute) can interfere in the learning, memory and anxiety in adult rats Materials and Methods: were used 196 albino rats Wistar and males, with 21 days of life. Initially, the animals were divided into two groups to compose the study 1 or 2. In study 1 the administration route was semi voluntary (6% ethanol) and in Study 2 was involuntary (by gavage intragástrica- ethanol 1g / kg). In both studies, the animals were divided again in relation to the type of beverage that receive (water or ethanol) and time consumption (acute- 2 hours or chronic for 21 days, whereas in Study 2 the alcohol consumption occurred every 3 days). On the 23rd days (48 hours after the last alcohol consumption) the animals were tested in Recognition Memory Test (RMT), the Elevated Plus Maze (EPM) and Morris Water Maze (MAM) for two consecutive days (and retested after 28 days). Results: In study 1 the results indicated that abstinence to ethanol after acute or chronic ethanol consumption was not able to alter the learning and spatial memory in LAM, but damage on long-term spatial memory were observed in animals submitted to consumption acute ethanol. No changes were observed in recognition memory in Session training and Short-term recognition memory, but the acute ethanol exposure was able to generate damages on long-term recognition memory. There were no differences in anxiety levels of study animals. Regarding the study 2, we observed that abstinence after acute ethanol consumption was able to generate damage in spatial memory short term and that chronic and acute consumption of ethanol were not able to alter the Recognition Memory of animals studied. Although, animals exposed to acute and chronic ethanol consumption in abstinence to 48 hours ethanol showed elevated levels of anxiety. Conclusion: Ethanol affects differently the spatial memory, recognition memory and anxiety levels depending on the route of administration (and therefore the amount of intake of ethanol) and of the time consumption.