Science Daily gets primitive with research into how the oldest parts of our brains help us learn:
Many of the mundane skills that we apply every day, such as buttoning up a shirt or playing an instrument, comprise a sequence of discrete movements that must be carried out in the correct order. Scientists have long known that there are two learning systems for such patterns of movement; with the implicit system, we learn without being aware of the fact and without conscious training, such as through simple repetition. The explicit system, on the other hand, we use when we consciously train and are aware of what we are learning.
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While they found a correlation between D2 receptor density and both forms of learning, they also noted that the evolutionarily oldest part of the basal ganglia – the limbic striatum – was only involved in implicit learning.“In other words, we probably have certain fundamental learning systems in common not only with rats, mice and other mammals, but also with the most primitive vertebrates, which also have a limbic striatum,” says Dr [Fredrik Ullén from Karolinska Institutet and the Stockholm Brain Institute].