Dados do Trabalho

Título

Investigation between a Mozart sonata effect on contextual memory extinction

Resumo

Introduction: Memory consists in the capacity of storing and recalling information acquired through experiences. After consolidated it can be kept, if repeatedly evoked, or extinguished. Memory extinction is as important as its formation, since it demonstrates the capacity of suppressing thoughts and/or behaviors no longer needed. This process does not imply experience elimination, but it’s ressignification. Despite the known music beneficial effects on the brain, especially Mozart’s K448 sonata, few is known about its potential on memory extinction.

Aims: Investigate Mozart’s K448 sonata effects on contextual memory extinction in mice.

Methods: The project was accomplished with 41 C57BL/6J mice, divided into G1: Mozart (n=14), G2: Ambience (n=14) and G3: Control (n=13). Only the first group was exposed to music from 9:00 pm to 7:00 am throughout the project, since intrauterine life. Groups 2 and 3, however, were only exposed to ambient noise. From the 50th to the 54th day, the animals underwent Habituation, in order to control behavioral interferences in response to the testing ambient differences. On the 55th day the Aversive Training was performed with groups 1 and 2. On the 82nd day all groups began Extinction Test, which lasted five consecutive days. All groups then underwent Recall Test on the 107th day. The procedures were recorded for analysis. Repeated measures ANOVA Test was used to analyze Extinction Text and One-Way ANOVA Test to Recall Test. Values of p≤0,05 were considered significant.

Results: The statistical analysis demonstrated that the fear extinction process varies amongst groups, despite the reduction of the freezing time for all of them during the tests. In general G1’s freezing time was longer than G2’s. On the first day of extinction G1’s freezing time was longer than G2’s e G3’s, whilst on the second day it was only longer than G3’s. At last, on the fifth day, G1’s freezing time was shorter than G2’s. Amongst the second and third day of extinction, G1’s freezing time reduced more than G3’s, whilst amongst the fourth and the fifth day, G1 upholded its freezing time, whilst G2’s extended. On recall, G1’s freezing time was longer than G3’s. All analysis were statistically significant (p≤0,05)

Conclusion: It was noted that mice exposed to Mozart’s K448 sonata were more reactive to aversive stimulus. However, they exhibited faster contextual memory of fear extinction.

Palavras Chave

Fear; Memory; Music; Amnesia, Retrograde.