8 Where We Might Go?
Outline1: The vocal organs in humans are not designed for speaking in the beginning;
The function for language is a byproduct during the process of evolution.
Outline2: Human reiterative ability is derived from something in regulating the motor control in basal ganglia.
Summary: Foxp2 is the gene in regulating our motor control and cognition. And this
cognitive ability can help us communicate with others effortlessly. If the mutations that disrupt foxp2 happen, this will cause us hard to comprehend other・s meanings and communicate with others. So the fact can explain that our reiterative capacity is closely related to the foxp2 gene. According to the studies Lieberman has discussed, human basal ganglia sequencing engine is the key to mark the human reiterative capacity. It seems that the basal ganglia sequencing engine plays an important part just like foxp2 gene in regulating our motor control and cognitive ability. The fact lets me think of a question, is the foxp2 gene located in the basal ganglia?
Outline3: The behavioral deficits are probably due to the sequencing engine problem.
Summary: The fact can be proved from insights from studies of Parkinson・s disease.
Patients with Parkinson・s disease will have serious apraxia due to the lesion of sequencing engine in regulation motor control.
Outline4: Different results in evolutionary process for foxp2 gene cause humans to have more linguistic abilities than other species.
Summary: Lieberman points the fact that in regulatory gene・s role in the embryonic development of the subcortical complex that plays a part in regulating these different aspects of human, chimpanzee, and mouse behavior. The fact explains that the foxp2 gene is not unique to humans. The difference in evolution in foxp2 gene is the key to mark human・s more linguistics abilities.
Outline5: Chimpanzees like human beings has joint attention that plays a role in the process which children learn words.
Summary: Humans can acquire other cultural aspects from interacting with other caretakers or adults, etc. This scenario can be also observed in chimpanzee・s society.
Chimpanzee infants can be observed to smile at their mothers when they look into each other・s open eyes. Besides, Lieberman points the fact that chimpanzees will give a negative reply to their enemies. The fact explains again that joint attention is not unique to humans.
Outline6: The degrees that joint attention operates in chimpanzees are probably the key to explain why chimpanzees can just have limited linguistic abilities.
Summary: Joint attention can be found in chimpanzees. The question is the degree to which these processes are operant in chimpanzees. However, this is still a mystery.
Outline7: The difference in genetic mechanisms among species causes them to have diverse linguistic abilities.
Summary: Humans have undergone more complete evolution in cognitive and motor control mechanisms, so they can have more linguistic abilities. They have neurotransmitters that other species might not have. Although we can also fine foxp2 genes in other species, the degrees in evolution in neural systems among species cause a vast effect on their linguistic abilities.
Outline8: To understand why and how humans acquire linguistic abilities, we must try to comprise other related sciences rather than see them disconnectedly.
Summary: Studies centered in a single department will not suffice. Lieberman hopes that the connection will be evident. These explain that how to comprise and observe from different viewpoints is necessary in understanding the complicated issue. However, Lieberman points that other sciences that focus on inorganic studies are helpless to find the solution to this issue.