Active Retrieval Improves Procedural Learning in Orthopedic Surgery.

OBJECTIVE: Tests are shown to enhance learning: this is known as the "testing effect". The benefit of testing is theorized to be through "active retrieval", which is the effortful process of recalling stored knowledge. This differs from "passive studying", such as reading, which is a low effort process relying on recognition. The testing effect is commonly studied in random word list scenarios and is thought to disappear as complexity of material increases. Little is known about the testing effect in complex situations such as procedural learning. Therefore, we investigated if testing improves procedural learning of fracture fixation as compared to "passive studying". DESIGN, SETTING, AND PARTICIPANTS: Fifty participants watched an instructional video of an open reduction internal fixation of a Sawbones™ femur. Participants then performed the procedure under guided supervision (pretest). After randomization, they either read the steps (passive studying group), or wrote down the steps from memory (active retrieval group) for a period of 15 minutes. After a washout period, all participants performed the procedure without guidance (posttest) and then once more, 1 week after the initial testing (retention test). The participants were assessed using the Objective Structured Assessment of Technical Skill. Each performance was video recorded for data analysis purposes. RESULTS: Participants in the passive studying group had significantly higher Objective Structured Assessment of Technical Skill scores during immediate assessment compared to the active retrieval group (p = 0.001), especially with respect to remembering the correct order of the steps (p = 0.002). The percentage of information forgotten was significantly less in the active retrieval group (p = 0.02) at the retention test. CONCLUSION: We demonstrated that, compared to passive studying, testing with active retrieval through writing resulted in better retention of fracture fixation knowledge (i.e., less forgetting). These findings can easily be applied and incorporated in existing curricula. Future studies are needed to determine the effects of different kinds of active retrieval methods such as verbal retrieval (e.g., dictating) in surgical practice.

Saccharomyces cerevisiae Tti2 Regulates PIKK Proteins and Stress Response.

The TTT complex is composed of the three essential proteins Tel2, Tti1, and Tti2 The complex is required to maintain steady state levels of phosphatidylinositol 3-kinase-related kinase (PIKK) proteins, including mTOR, ATM/Tel1, ATR/Mec1, and TRRAP/Tra1, all of which serve as regulators of critical cell signaling pathways. Due to their association with heat shock proteins, and with newly synthesized PIKK peptides, components of the TTT complex may act as cochaperones. Here, we analyze the consequences of depleting the cellular level of Tti2 in Saccharomyces cerevisiae We show that yeast expressing low levels of Tti2 are viable under optimal growth conditions, but the cells are sensitive to a number of stress conditions that involve PIKK pathways. In agreement with this, depleting Tti2 levels decreased expression of Tra1, Mec1, and Tor1, affected their localization and inhibited the stress responses in which these molecules are involved. Tti2 expression was not increased during heat shock, implying that it does not play a general role in the heat shock response. However, steady state levels of Hsp42 increase when Tti2 is depleted, and tti2L187P has a synthetic interaction with exon 1 of the human Huntingtin gene containing a 103 residue polyQ sequence, suggesting a general role in protein quality control. We also find that overexpressing Hsp90 or its cochaperones is synthetic lethal when Tti2 is depleted, an effect possibly due to imbalanced stoichiometry of a complex required for PIKK assembly. These results indicate that Tti2 does not act as a general chaperone, but may have a specialized function in PIKK folding and/or complex assembly.