A study on reference memory and working memory of pure cerebral concussion and multiple cerebral concussion by 8-arm radial maze in rats

Abstract

Objective To observe learning and memory behavior changes of one time cerebral concussion called pure cerebral concussion(PCC)and three times cerebral concussion called multiple cerebral concussion (MCC)after injured 24 days in rats.Methods A metallic pendulum striker device was deployed to duplicate PCC and MCC model in SD rata which were the complete closed head injury model.The animals were divided into PCC and MCC groups at random.One control group was used,each group has eight animals(n=8).One 8-arms radial maze was used to assessed each animal's capabilities,that is,spatial reference memory,working memory,spirited activity and take in food.Results Compared with control group,there were some significance(P＜0.05)in both experiment groups post injury,that was,(1)The food intake decreased,PCC group from the 1st to the 11th day(from 0.00±0.00 to 2.62±1.76)after injury,MCC group from the 1st day to the 24th day(from 0.00±0.00 to 0.75±1.48)after injury.(2)Spirited activity depressed,PCC group on the 1st to the 7th,13rd day(from 4.87±1.24 to 10.0±2.39)after injury,MCC group on the 1st to 8th,22nd day(from 4.25±5.03 to 9.37±4.20)after injury.(3)The spatial reference memory was lower in early then gradually increased,PCC group on the 1 st to 7th day(from 0.50±0.75 to 3.O0±1.06)after injury,MCC group from the 1st to 19th day(from 1.88±2.10 to 2.50±2.44)after injury.(4)The working memory was delaying damaged,PCC group from the 1st to the 6th day and the 10th to the 23rd day(from 0.00±0.00 to 4.25±3.05)after injury,MCC group on the 1～4th,6th,9～13th,15th,16th,19th～22nd day(from 0.25±0.46 to 3.12±2.87)after injury.Conclusion The injured rata'capability of spatial reference memory,working memory,spirited activity and food intake were obviously damaged after CC,and the MCC group's capability of spatial reference memory,spirited activity and food intake was worse than PCC group. Key words: Pure cerebral concussion; Multiple cerebral concussion; Reference memery; Working menmory; Rats