4.4.3. Spontaneous Alternation Behavior (SAB)

The SAB test is based on the exploratory strategy of rodents to explore a new environment. In examining repetitive behaviors, the Y maze test took advantage of the rodents’ natural tendency to spontaneously alternate or choose a different arm of the maze instead of the one they visited on their previous entry (i.e., least recently visited arm). A decrease in the percentage alternation can also be attributed to same arm repeated visits [100]. Spontaneous alternation behavior was measured on a Y maze apparatus, as previously described, with slight modifications. The Y maze composed of three arms (30 cm × 6 cm × 15 cm), where the arms were labeled with letters: A, B, or C. The test mouse was placed in the center of the maze and was allowed to freely explore the maze for 8 min. The number of entries into each arm and the total number of entries were recorded by the observer. A spontaneous alternation was defined as successive entry into three arms on an overlapping triplet set. Percentage spontaneous alternation was calculated as the number of spontaneous alternations (actual alternations) over the total number of entries (possible alternations). Two arm entries were subtracted from the denominator because an alternation required at least 3 entries. The apparatus was cleaned with 70% alcohol solution after each mouse was tested [101].

For example, the sequence C, B, A, B, C, B, A, C, B (starting in arm A) resulted in a percent spontaneous alternation of 5/7 = 71.4%.