[MUSIC] So, last time we considered the nature of age of acquisition, and specifically we looked at, the development of the brain,. Right, from sensory and motor areas developing earlier in life with other areas that integrate across senses and across sensory motor domains as de developing later in life. We also looked at the progression from primary, to secondary, to tertiary within sensory areas. And, we considered how this might affect the development of behavior. So for example, when we look at early versus late learned words, there's an idea in the literature that early learned words may be based more on the sound of the word, and late learned words may be more conscious or more effortful. And this is revealed in brain scans, with monolinguals. Furthermore, it expands to non-verbal domains. So we can consider things like music, and the fact that a musician may be trained early or later in life, effects the brain systems involved and the ways in which they process information in the world. And this also appears in domains such as sports. Where we can see again, golf putters differ in their ability to putt a golf ball, and what gets in the way of that putting depends on when golf was initially learned. Finally we end it with this idea that, speech and the sounds produced in speech are related to grammar. And we'll build on this idea in this segment by considering the nature of speech, sounds, accent, and grammar, in a second language. And how age may play a role in the development of those three things.