Intrahippocampal Anisomycin Impairs Spatial Performance on the Morris Water Maze.

New memories are thought to be solidified (consolidated) by de novo synthesis of proteins in the period subsequent to learning. This view stems from the observation that protein synthesis inhibitors, such as anisomycin (ANI), administered during this consolidation period cause memory impairments. However, in addition to blocking protein synthesis, intrahippocampal infusions of ANI cause the suppression of evoked and spontaneous neural activity, suggesting that ANI could impair memory expression by simply preventing activity-dependent brain functions. Here, we evaluated the influence of intrahippocampal ANI infusions on allocentric spatial navigation using the Morris water maze, a task well known to require dorsal hippocampal integrity. Young, adult male Sprague Dawley rats were implanted with bilateral dorsal hippocampal cannulae, and their ability to learn the location of a hidden platform was assessed before and following infusions of ANI, TTX, or vehicle (PBS). Before infusion, all groups demonstrated normal spatial navigation (training on days 1 and 2), whereas 30 min following infusions (day 3) both the ANI and TTX groups showed significant impairments in allocentric navigation, but not visually cued navigation, when compared with PBS-treated animals. Spatial navigational deficits appeared to resolve on day 4 in the ANI and TTX groups, 24 h following infusion. These results show that ANI and TTX inhibit the on-line function of the dorsal hippocampus in a similar fashion and highlight the importance of neural activity as an intervening factor between molecular and behavioral processes. SIGNIFICANCE STATEMENT: The permanence of memories has long thought to be mediated by the production of new proteins, because protein synthesis inhibitors can block retrieval of recently learned information. However, protein synthesis inhibitors may have additional detrimental effects on neurobiological function. Here we show that anisomycin, a commonly used protein synthesis inhibitor in memory research, impairs on-line brain function in a way similar to an agent that eliminates electrical neural activity. Since disruption of neural activity can also lead to memory loss, it may be that memory permanence is mediated by neural rehearsal following learning.

Psychiatric hospital experiences that support and frustrate emerging adults' psychological needs: A self-determination theory perspective.

AIM: There are international efforts to implement developmentally appropriate and youth-oriented mental health services for emerging adults to increase treatment engagement and the success of early intervention. While significant progress has been made in developing community service models, limited research has focused on how to design psychiatric inpatient settings that promote the recovery of emerging adults. The present study attempts to address this knowledge gap through a qualitative exploration of hospital experiences that influence psychological need satisfaction and frustration, as defined by self-determination theory (SDT). METHODS: Inpatients (N = 104) from an emerging adult psychiatry unit were interviewed regarding hospital experiences that related to satisfaction or frustration of SDT needs for autonomy, competence, and relatedness. RESULTS: A basic interpretative qualitative analysis highlighted six key aspects of the hospital experience relevant to these needs: (a) social interactions, (b) freedom of behaviour and access, (c) programs and activities, (d) treatment collaboration and choice, (e) restraining/unpleasant hospital practices, and (f) progress, symptoms, and functioning. The findings support SDT's emphasis on the importance of autonomy support, structure, and involvement for need satisfaction. CONCLUSIONS: The study sheds light on aspects of the hospital milieu that may be essential to recovery-oriented inpatient care and on experiences that may be distinctly important for emerging adults, such as support for independence and the opportunity to relate to same-age co-patients experiencing similar mental health problems and life circumstances.