Working memory performance and cognitive flexibility after dexamethasone or hydrocortisone administration in healthy volunteers

Abstract Background Zebrafish are growing in use as a model for understanding drug dependence and addiction. Sensitization paradigms have been a useful tool in identifying mechanisms involved in drug-induced behavioral and neurological changes, but in zebrafish have tended to focus on locomotor, rather than cognitive, endpoints. Methods Here, we used a novel method, the FMP Y-maze, which measures continuous performance through a series of repeated binary choices (L vs R), to establish a model for assessing parameters associated with psychostimulant-induced behavioral and cognitive sensitization in adult zebrafish. Results Repeat, intermittent exposure to d-amphetamine (AMPH) for 14 days increased alternations (LRLR) in the maze, suggesting improved working memory, which was enhanced further following drug challenge after a short withdrawal period, suggesting behavioral sensitization. However, this cognitive enhancement coincided with a reduction in the use of other exploration strategies, hypolocomotion, and inhibition of cognitive flexibility. Like AMPH, exposure to nicotine (NIC) increased alternations following drug challenge after chronic treatment. Repeat NIC exposure appeared to induce both cognitive and psychomotor sensitization, as evidenced by increased working memory performance (alternations) and locomotor activity, without negatively impacting other search strategies or cognitive flexibility. Conclusion Chronic treatment with AMPH or NIC boosts cognitive performance in adult zebrafish. Cognitive sensitization occurred with both drugs, resulting in enhanced working memory; however, repeat AMPH exposure, following a withdrawal period, resulted in inhibited cognitive flexibility, an effect not evident with repeat NIC exposure. Cognitive and behavioral sensitization paradigms in zebrafish could serve as a useful tool for assessing cognitive states which result in cognitive enhancing or impairing effects of drugs.

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Political Ideology and Executive Functioning: The Effect of Conservatism and Liberalism on Cognitive Flexibility and Working Memory Performance

Social Psychological and Personality Science ◽

10.1177/1948550620913187 ◽

2020 ◽

pp. 194855062091318

Author(s):

Bryan M. Buechner ◽

Joshua J. Clarkson ◽

Ashley S. Otto ◽

Edward R. Hirt ◽

M. Cony Ho

Keyword(s):

Working Memory ◽

Cognitive Flexibility ◽

Political Ideology ◽

Memory Performance ◽

Self Control ◽

Cognitive Factors ◽

Memory Processes ◽

The Impact ◽

Different Levels

Although models of political ideology traditionally focus on the motivations that separate conservatives and liberals, a growing body of research is directly exploring the cognitive factors that vary due to political ideology. Consistent with this emerging literature, the present research proposes that conservatives and liberals excel at tasks of distinct working memory processes (i.e., inhibition and updating, respectively). Consistent with this hypothesis, three studies demonstrate that conservatives are more likely to succeed at response inhibition and liberals are more likely to succeed at response updating. Moreover, this effect is rooted in different levels of cognitive flexibility and independent of respondents’ demographics, intelligence, religiosity, and motivation. Collectively, these findings offer an important perspective on the cognitive factors that delineate conservatism and liberalism, the role of cognitive flexibility in specific working memory processes, and the impact of political ideology on a multitude of behaviors linked to inhibition and updating (e.g., creativity, problem-solving, self-control).

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