Compared with environmentally impoverished rats, those rats housed in enriched environments experienced a dramatic increase in the number of their:

synapses

Explanation:

In mammals brain, synapse has the function to pass electric or chemical signals from one neuron to another. In an enriched environment, the rats would most likely encountered far more stimulus compared to environmentally impoverished rats. This will make their brain become used to conducting more activities compared to environmentally impoverished rats, which will lead to the dramatic increase in the number of their synapses.

Synapses

Explanation:

This question refers to an experiment that has to do with psychology and the effect of the environment on children development.

The researchers wanted to know how an enriched environment would affect the development of kids in comparison to the development of the kids who were grown in impoverished environments.

They took two groups of rats and noticed that the ones that had an enriched environment experimented a dramatic increase in the number of their synapses.

It is important to remember that a synapse is a small gap between the neurons that allows one neuron to pass information onto the other neuron. An increased of synapses implies more passing of information and has to do with a better memory.