1 Certain parts of the brain shrink, especially the prefrontal cortex (an area at the front of the frontal lobe) and the hippocampus. 2  Both areas are important to learning, memory, planning, and other complex mental activities.
Some big, fluffy dog breeds are the chow chow, the samoyed, the standard poodle, the old English sheepdog and the keeshond. The abundant, fluffy coats of these dogs require constant care. Keep Learning.
The English mastiff is one of the largest dog breeds in the world, especially in terms of body mass. The first mentions of these massive dogs date back to as early as the 6th century BC. During the Roman conquest of England, the loyalty and strength of mastiff impressed even Caesar.