RESUMEN

A fundamental trait of depression is low motivation. Hippocampal neurogenesis has been associated with motivational deficits but detailed evidence on how it regulates human-relevant behavioral traits is still missing. We used the hGFAP-TK rat model to deplete actively dividing neural stem cells in the rat hippocampus. Use of the effort-discounting operant task allowed us to identify specific and detailed deficits in motivation behavior. In this task, rats are given a choice between small and large food rewards, where 2-20 lever presses are required to obtain the large reward (four sugar pellets) versus one press to receive the smaller reward (two sugar pellets). We found that depleting adult neurogenesis did not affect effort-based choice or general motivation to complete the task. However, lack of adult neurogenesis reduced the pressing rate and thus increased time to complete the required presses to obtain a reward. In summary, the present study finds that adult hippocampal neurogenesis specifically reduces response vigor to obtain rewards and thus deepens our understanding in how neurogenesis shapes depression.

Asunto(s)

Neurogénesis , Recompensa , Humanos , Ratas , Animales , Hipocampo , Motivación , Azúcares , Conducta de Elección/fisiología

RESUMEN

OBJECTIVE: To synthesize qualitative literature exploring the lived experience of healthcare workers (HCWs) who cared for patients during the following infectious disease outbreaks (IDOs): the 2003 SARS epidemic, 2009 H1N1 pandemic, 2012 MERS outbreak, and 2014 EVD epidemic. We aim to reveal the collective experience of HCWs during these four IDOs and to create a reference for comparison of current and future IDOs. METHODS: Three electronic databases were searched, yielding 823 results after duplicates were removed. Forty qualitative and mixed-methods studies met the criteria for full file review. Fourteen studies met the inclusion and exclusion criteria. The data from the Results or Findings sections were manually coded and themes were conceptualized using thematic analysis. RESULTS: Of the 14 studies, 28.6% focused on SARS, 21.4% on H1N1, 21.4% on MERS, and 28.6% on EVD. Studies occurred in six different countries and included physicians, nurses, paramedics, and emergency medical technicians as participants. Five themes were conceptualized: Uncertainty, Adapting to Change, Commitment, Sacrifice, and Resilience. CONCLUSION: This review identified the collective experience of HCWs caring for patients during four 21st century IDOs. This qualitative systematic review offers a reference to compare similarities and differences of other IDOs, including the COVID-19 pandemic.