Eight-arm radial maze

Ginseng extract improves the spatial learning performance of aged rats in an eight-arm radial maze and operant discrimination task (Nitta et al. 1995). It also improves memory performance in active-avoidance (shuttle-box) and passive-avoidance (step-down) tasks, and reinforces staircase-maze learning in both young and aged rats. (Petkov and Mosharrof 1987 Petkov et al. 1990 Petkov et al. 1992). The effects were also very dose dependent, with inverted U-shape dose-response curves. 

Santucci D, Rankin J, Laviola G, et al. 1995. Eight-arm radial maze performance and hippocampal nerve growth factor levels in adult C57B1/6J mice following prenatal exposure to aluminum. [Abstract]. Behavioral brain research in naturalistic and semi-naturalistic settings (NATO ASI series D, No. 82). 

On an eight-arm radial maze containing seven black arms and one white arm, rats rapidly learned to enter the white arm first when it was the only arm containing food. 

GYKI-46903 (173 Egis Gyogyszergyar) is a potent 5-HT, antagonist (Xi = 20 2 nM) reported to be under development as a potential treatment for dementia (487,488).In rats, GYKI-46903 was shown to attenuate scopolamine-induced memory impairments in the stepdown passive-avoidance task and the eight-arm radial maze (489). 

Iwashita, A., Hisajima, H., Notsu, Y., and Okuhara, M., Effects of basic fibroblast growth factor and ganghoside GM1 on neuronal survival in primary cultures and on eight-arm radial maze task in adult rats following partial fimbria transections, Naunyn-Schmiedebergs Arch. Pharmacol., 353, 342, 1996. 

Figure 19 Effect of DHA-rich Chlorella oil-diet on eight-arm radial maze performance of aged mice. Each column and vertical bar represents the means SE of 20 trials (5-7 mice).

Egashira, N., Mishima, K., Iwasaki, K., and Fujiwara, M. (2002) Intracerebral microinjections of delta 9-tetrahydrocannabinol search for the impairment of spatial memory in the eight-arm radial maze in rats. Brain Res, 952 239 5. 

Although path integration is often thought of as a simpler or more primitive spatial mechanism, some evidence suggests it may be involved in complex maze behavior in rats. In a classic experiment performed by Olton and Samuelson (1976), food was placed in a cup at the end of each of eight arms on a radial maze, and rats were allowed to explore the maze until they had entered each arm and consumed its reward. Over several... 

The radial maze consists of eight dead-end arms arranged like spokes around a central chamber (Fig. 6a). The spatial memory and foraging behavior of the animal can be studied after it has been released in the maze. In one variant, hungry rats are presented with one food pellet at the end of each arm and given a limited time to feed. Parameters typically recorded include number of arms repeatedly visited, or omitted, and time to complete the maze. Rats with impaired short-term memory function will do poorly in this maze. 

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