Sunday, December 09, 2007

Is the Juice Worth the Squeeze?

Rats weigh out decisions just like humans do, according to a new study conducted on Wistar mice, which are rodent specifically developed for research. This study serves as the first to show that a non-human animal is capable of carefully analyzing the potential costs and benefits of a situation and then make a decision based on the conclusion. They are able to do this be creating a ratio or standard enabling them to decide between options that require different levels of effort and yield different levels of rewards. Ruud van den Bos, who led the research, has said that in a natural habitat rats are constantly facing a degree of uncertainty because little is under their control. Examples of this are the amount and quality of patches of food that are available to the rats, which varies over time due to things like locations and weather conditions.

Van den Bos, who is a scientist in the Faculty of Veterinary Medicine at Utrecht University in The Netherlands also added that because of the varying obstacles, an amount of energy must be used to obtain different items. Along with his research team, he attempted to recreate these challenges by constructing a “T” shaped course in which the rats would be able to receive certain rewards depending on the route that they took. At the end of each arm of the “T” were different rewards- one arm containing little obstacle and little reward, while the other contained much more obstacle but a much higher reward. At first the rats immediately went for the easier route, which contained one sugar pellet. After realizing that more treats could be possible, they opted for the opposite route, but only until a certain point. The other route had 3 to 5 sugar pellets available, but also had steep barriers that the rats would have to climb in order to seek out the reward. When the effort surpassed a certain point, the rats stuck to the smaller treat. The researchers also believe that the rats behave according to an internal constant standard. The standard varied which each situation and is possibly part inherent and part determined by the individual. This research is important in understanding how animals other than humans are capable of determining choices and making decisions that are in their best interest.

Posted by amolina (11)


Post a Comment

<< Home