Anatomists know very well about all the organs of our body except one. That is brain. Though brain is a walnut shaped gray lump with some quantity, the mind that emerges from the brain pervades the whole universe. The convergence of the mind and matter is still an enigma that has to be explored. Brain helps us feel the pain in any part of the body but it itself doesn't have the ability to feel pain. This is another amazing thing. As I'm a student of Linguistics, I studied a bit about brain especially the so called language areas in Brain. Neuro surgeons Broca and Wernicke found some points in the left hemisphere of the brain and located in the sylvian fissure or lateral sulcus where most of the language processing is said to take place. But after the advent of sophisticated biomedical instruments like fMRI and PET scans neurologists are able to see the thoughts of their patients. Though the language processing is said to take place in two points located in and around lateral sulcus, and language is predominantly a left hemisphere specialization, when they used fMRI scan they observed that even many of the areas in the right hemisphere also got activated.
The renowned professor in Linguistics who introduced bio-linguistics approach said proposed innateness hypothesis and said that the language internalizing abilities are acquired by children by birth. So a newborn child enters this world with built in language capabilities that are hardwired into brain in the form of language templates. Chomsky said that there are language universals which are common to all the languages on this earth. For example, all the languages spoken by different communities, nationalities and tribes have many similar qualities like they all have sounds, words, sentences and nouns etc. In spite of all the differences among the languages there are many features that are in common and Chomsky termed them as language universals. Language universals are embedded in the form of templates and help the children to internalize their mother tongue at an amazing pace. Once a child gets exposed to a language it gets used to that particular language and other language templates slowly get discarded. These language universals constitute universal grammar and Universal Grammar enables children to acquire their mother tongue in spite of the fact that they face the problem of poverty of stimulus.
The Harvard psychologist B.F Skinner who introduced Behaviorism stated that humans do not get anything by birth but they learn or acquire everything by a process called stimulus-response and reinforcement. But Chomsky stated that children do not actually get adequate stimulus from their parents or the people in the vicinity. Even if they get some stimulus it is found to be imperfect. Most of the parents are not positively inclined to correct the language related mistakes of their children and even the children do not like to be corrected for their mistakes. So Chomsky says that there is in fact poverty of stimulus and the universal language or the LAD (Language Acquisition Device) which is said to be hard wired into the brain helps the children to overcome this problem of poverty of stimulus.