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1.
Neuropsychology ; 36(6): 540-551, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35737534

RESUMO

OBJECTIVE: Memory deficits in individuals with schizophrenia are well-established, but less is known about how schizophrenia affects metacognitive processes such as metamemory. We investigated metamemory ability using the value-directed remembering task, which assesses the degree to which participants use value cues to guide their learning of a list of items (i.e., their memory selectivity). METHOD: Participants were patients undergoing treatment following a recent first episode of schizophrenia (n = 20) and demographically comparable healthy controls (n = 18). Participants viewed six lists of 24 words where each word was paired with either a low value (1-3 points) or a high value (10-12 points), and they were instructed to maximize their score on free recall tests given after each list. After the final free recall test, participants completed a recognition test where they gave remember/know judgments. RESULTS: On tests of free recall, patients showed reduced memory selectivity relative to healthy controls. On the recognition test, patients failed to show an effect of value on recognition of nonrecalled words, in contrast to healthy controls, who showed a significant value effect that was characterized by greater "remember" judgments. Patients initially overestimated their memory capacity but were able to adjust their estimates to be more accurate based on task experience. Patients' self-reports of memory selectivity were unrelated to their actual memory selectivity. CONCLUSIONS: Patients with first-episode schizophrenia had substantial impairments on the value-directed remembering task, but areas of preserved metamemory ability were also observed. These findings have potential implications for cognitive training interventions. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Metacognição , Esquizofrenia , Humanos , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Transtornos da Memória/psicologia , Rememoração Mental , Reconhecimento Psicológico , Esquizofrenia/complicações
2.
Front Psychol ; 11: 604978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343476

RESUMO

Previous work has shown that memory performance in older adults is affected by activation of a stereotype of age-related memory decline. In the present experiment, we examined whether stereotype threat would affect metamemory in older adults; that is, whether under stereotype threat they make poorer judgments about what they could remember. We tested older adults (M Age = 66.18 years) on a task in which participants viewed words paired with point values and "bet" on whether they could later recall each word. If they bet on and recalled a word, they gained those points, but if they bet on and failed to recall a word, they lost those points. Thus, this task required participants to monitor how much they could remember and prioritize high value items. Participants performed this task over six lists of items either under stereotype threat about age-related memory decline or not under stereotype threat. Participants from both groups performed similarly on initial lists, but on later lists, participants under stereotype threat showed impaired performance as indicated by a lower average point score and a lower average gamma coefficient. The results suggest that a modest effect of stereotype threat on recall combined with a modest effect on metacognitive judgments to result in a performance deficit. This pattern of results may reflect an effect of stereotype threat on executive control reducing the ability to strategically use memory.

3.
Neurobiol Learn Mem ; 175: 107316, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33011387

RESUMO

There is substantial evidence linking early-life stress (ELS) to negative health outcomes in adulthood, including addiction. However, the neurocognitive and behavioral mechanisms through which ELS increases these risks remain unclear. To address this gap in knowledge, we developed a novel instrumental learning paradigm to explore the effects of ELS on the balance of habitual versus goal-directed learning. Habits efficiently reproduce repetitive behaviors but are inflexible whenreward contingencies related to those behaviors change. Persisting in performing a response after its outcome has been devalued is the hallmark of habitual behavior in instrumental learning. Participants with a history of higher ELS were significantly more likely to make habitual responses in this instrumental avoidance learning paradigm than individuals with a history of lower ELS. Logistic regression analysis showed that ELS is significantly related to habitual responding over and above the effects of retrospective socioeconomic status, trait and state anxiety, depression and recent levels of stress. Analysis of the differential impacts of the type of ELS suggested that these effects are largely driven by experiences of physical neglect.


Assuntos
Experiências Adversas da Infância/psicologia , Aprendizagem da Esquiva , Condicionamento Operante , Hábitos , Adolescente , Adulto , Ansiedade/psicologia , Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/psicologia , Depressão/psicologia , Abuso Emocional/psicologia , Feminino , Humanos , Masculino , Personalidade , Abuso Físico/psicologia , Classe Social , Adulto Jovem
4.
Front Psychol ; 10: 1876, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456726

RESUMO

The effect of stress on the balance between goal-directed behavior and stimulus-response habits has been demonstrated in a number of studies, but the extent to which stressful events that occur during development affect the balance between these systems later in life is less clear. Here, we examined whether individuals with a history of early-life stress (ELS) show a bias toward avoidance habits on an instrumental learning task as adults. Participants (N = 189 in Experiment 1 and N = 112 in Experiment 2) were undergraduate students at the University of California, Los Angeles. In Experiment 1, we hypothesized that a history of ELS and a longer training phase would be associated with greater avoidance habits. Participants learned to make button-press responses to visual stimuli in order to avoid aversive auditory outcomes. Following a training phase involving extensive practice of the responses, participants were tested for habitual responding using outcome devaluation. After completing the instrumental learning task, participants provided retrospective reports of stressful events they experienced during their first 16 years of life. We did not observe evidence for an effect of the length of training, but we did observe an effect of ELS, with greater stress predicting greater odds of performing the avoidance habit. In Experiment 2, we sought to replicate the effect of ELS observed in Experiment 1, and we also tested whether the presence of distraction during training would increase avoidance habit performance. We replicated the effect of ELS but we did not observe evidence of an effect of distraction. Taken together, these data lend support to the hypothesis that stress occurring during development can have lasting effects on the balance between goal-directed behavior and stimulus-response habits in humans. Enhancement of avoidance habits may help explain the higher levels of negative health outcomes such as heart and liver disease that have been observed in individuals with a history of ELS. Some of the negative health behaviors that contribute to these negative health outcomes, e.g., overeating and substance use, may be performed initially to avoid feelings of distress and then transition to being performed habitually.

5.
Curr Top Behav Neurosci ; 37: 275-295, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27677776

RESUMO

Data from experimental animals and human subjects has provided convergent evidence for the key role of the striatum in the formation of stimulus-response habits. Habits can be distinguished from associative memories that support goal-directed actions based on their insensitivity to reward devaluation and contingency degradation. Behavior on many instrumental learning tasks can be supported by both declarative knowledge and habits, and these contributions shift with the amount of training. This shift appears to be accompanied by the involvement of different cortico-striatal loops in controlling behavior. Factors that encourage the shift toward and maintenance of habits include learning under conditions of stress, distraction, and interval or probabilistic schedules of reinforcement.


Assuntos
Corpo Estriado/fisiologia , Hábitos , Aprendizagem/fisiologia , Memória/fisiologia , Neostriado/fisiologia , Animais , Humanos
6.
Exp Brain Res ; 234(11): 3107-3118, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27349996

RESUMO

The ability to inhibit unwanted responses is critical for effective control of behavior, and inhibition failures can have disastrous consequences in real-world situations. Here, we examined how prior exposure to negative emotional stimuli affects the response-stopping network. Participants performed the stop-signal task, which relies on inhibitory control processes, after they viewed blocks of either negatively emotional or neutral images. In Experiment 1, we found that neural activity was reduced following negative image viewing. When participants were required to inhibit responding after neutral image viewing, we observed activation consistent with previous studies using the stop-signal task. However, when participants were required to inhibit responding after negative image viewing, we observed reductions in the activation of ventrolateral prefrontal cortex, dorsolateral prefrontal cortex, medial frontal cortex, and parietal cortex. Furthermore, analysis of neural connectivity during stop-signal task blocks indicated that across participants, emotion-induced changes in behavioral performance were associated with changes in functional connectivity, such that greater behavioral impairment after negative image viewing was associated with greater weakening of connectivity. In Experiment 2, we collected behavioral data from a larger sample of participants and found that stopping performance was impaired after negative image viewing, as seen in longer stop-signal reaction times. The present results demonstrate that negative emotional events can prospectively disrupt the neural network supporting response inhibition.


Assuntos
Sintomas Afetivos/complicações , Mapeamento Encefálico , Encéfalo/fisiopatologia , Disfunção Cognitiva/etiologia , Inibição Psicológica , Adolescente , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imaginação , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Estimulação Luminosa , Psicofísica , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
7.
Hippocampus ; 23(11): 1025-34, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23929764

RESUMO

People experiencing early-life stress (ELS) exhibit increased incidence of behaviors that lead to addiction and obesity as adults. Many of these behaviors may be viewed as resulting from an overreliance on habits as opposed to goal-directed instrumental behavior. This increased habitization may result from alterations in the interactions between dorsolateral striatum-dependent and hippocampus-dependent learning systems. As an initial examination of this idea, we investigated the effect of ELS on instrumental learning and extinction. In Experiment 1, we examined the effect of ELS in two groups of people, one trained on a continuous reinforcement schedule and one trained on a partial reinforcement schedule. We found that people who experienced ELS had a diminished effect of the partial reinforcement schedule on extinction. In Experiment 2, we again manipulated reinforcement schedule and also challenged declarative memory by requiring subjects to perform a concurrent task. We found that the declarative challenge did not affect extinction responding in the non-ELS group. In a moderate-ELS group, we observed a diminished sensitivity to the reinforcement schedule during extinction only under divided attention. In the high-ELS group, we observed a reduced sensitivity to reinforcement schedule even in the absence of the declarative memory challenge, consistent with Experiment 1. Our results suggest that ELS reduces the tendency to use declarative, hippocampus-dependent memory in instrumental tasks in favor of habits. ELS may affect hippocampal development, thus altering the interaction between memory systems and potentially contributing to poor health outcomes.


Assuntos
Condicionamento Operante/fisiologia , Memória/fisiologia , Estresse Psicológico , Adolescente , Corpo Estriado/fisiologia , Extinção Psicológica , Feminino , Hábitos , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Masculino , Obesidade/etiologia , Esquema de Reforço , Recompensa , Transtornos Relacionados ao Uso de Substâncias/etiologia , Biologia de Sistemas , Adulto Jovem
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