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  1. Section Editor(s): Carroll, V. Susan

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How are humans different from other animals? What unique characteristics set us apart from other mammals? Language? Many other mammals-dolphins, chimps, dogs-communicate in meaningful ways with each other. Tools? Again, many other mammals use tools in their every day lives. Emotions? We observe behaviors in other mammals that appear similar to human emotion. The Public Broadcasting System recently aired a series-"The Human Spark"-that examines these questions. In the three-part series, host Alan Alda joins neuroscientists, archeologists, and primatologists as they try to explain the nature of "human uniqueness." Using state-of-the-art, high-tech imaging techniques as well as low-tech but scientifically sound laboratory studies of primates, dogs, and human children, scientists examine the ways in which we are similar and those in which we differ.

  
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Some of the early evidence of human uniqueness exists in the cave paintings found in southern France. Thirty thousand years ago, our Neanderthal predecessors created extraordinary art that demonstrates imagination, representational thinking, and perhaps a sense of spirituality that we share. Archeological evidence indicates that the Neanderthals lived cooperatively within some sort of social network. However, the Neanderthal line did not survive, leading scientists to ask what really makes us different. Brain size alone? Spoken language or other means of social communication? Better cognitive sequencing?

 

Alda observed the chimps and participated in experiments with them; he and the researchers studying these primates observed the continuity and discontinuity between their skills and ours. Chimps "make" tools and use them efficiently, but they do not save the tools for future, repeated use as we do. Chimps live in social networks that include empathy and cooperation, but these traits are limited-for example, sharing food rewards occurs rarely despite nonverbal cues from others in the network. They do not seem to attend to the concerns of others in the group; social understanding is limited.

 

The story of the FOXP2 gene may explain how we made the neurological "jump" that explains our uniqueness. Human cognition and abstract thought rely on language. In 1995,Vargha-Khadem et al. published an article that investigated a familial language disorder, a verbal apraxia, linked to a bilateral reduction in the size of affected individuals' caudate nucleus. Six years later, other researchers announced that they had linked a mutation in a single gene to this language disorder. Named FOXP2, this gene contains a forkhead domain that facilitates transcription from DNA to RNA. Human FOXP2 differs from chimp FOXP2 in two amino acids; these mutations occurred between 10,000 and 100,000 years ago and have been critical for the development of human speech and the evolution of language-critical components of human uniqueness. Language and speech provide us with representational thinking and the ability to conceptualize what others might be thinking.

 

Finally, Alda and the neuroscientists using high-tech imaging demonstrated that humans may be the most creative when we are idle, that we are best able to tap into intentionality when we are "not thinking" actively. We are able to think of ourselves in others' lives and to think in terms of others' concerns. We anticipate what others might think about a particular event, experience, or idea. Even very young children "read" the intentions of others and behave in response to these.

 

What do all of these findings mean to us as neuroscience nurses? Many of our patients experience changes in their ability to communicate using spoken language. If we believe that this ability makes us unique, then we need to help them compensate for dysfunction. We need to look for ways to support their unique losses and remaining skills. We need to use our own insights into human behavior, cooperation, and empathy to provide the best care possible. As neuroscience nurses, we are "intentional" care providers, thinking in terms of others' concerns. We can also use all of our high-tech, scientifically sophisticated knowledge and equipment to help our patients and their families understand and cope with neurological dysfunction. We can be a spark!

 

Reference

 

Vargha-Khadem, F., Watkins, K., Alcock, K., Fletcher, P., & Passingham, R. (1995). Praxic and nonverbal cognitive deficits in a large family with genetically transmitted speech and language disorder. Proceedings of the National Academy of Sciences, USA, 92, 930-933. [Context Link]