**2. Results**

### *2.1. Morris Water Maze Test*

Figure 1A represents the escape latency intervals recorded during successive training trials. In the acquisition trials, the TMT group showed deteriorated cognitive deficits compared with the normal group, reflected by the increased escape latency (\*\*\* *p* < 0.001, on Days 1 and 4, \*\* *p* < 0.01, on Days 2 and 3). The TMT + Bean-PS group demonstrated amelioration of spatial memory and learning ability relative to the TMT group starting from Day 2 (*p* < 0.05) and Day 4 (*p* < 0.05). In the retention test, the times spent on the platform varied significantly among the groups. The TMT group spent less time on the platform than the normal group (F2, 18 = 6.42, *p* < 0.05). The TMT + Bean-PS group did not affect the time spent in the platform area as seen in Figure 1B.

**Figure 1.** Effects of soy-bean-derived phosphatidylserine (Bean-PS) on spatial learning and memory dysfunction in trimethyltin (TMT)-induced rats. (**A**) The latency in escaping onto the hidden platform during the acquisition test. In the acquisition test, the task entailed three trials each day over 4 days. The values are presented as mean ± S.E.M. \*\* *p* < 0.01, \*\*\* *p* < 0.001 vs. normal group, # *p* < 0.05 vs. TMT group, respectively. (**B**)Retention was tested on Day 5. Results are expressed as means ± S.E.M. \*\* *p* < 0.01 vs. normal group. Normal group (*N* = 9); TMT group (*N* = 5); TMT-Bean-PS (*N* = 5).

**B** 
