Monday, October 18, 2010

"I have just awakened for the first time!"

In this blog I want to pose a different hypothetical situation to think about: what if your life was only contained in short bursts? If you literally lived minute by minute? For one man in particular this has been his life for the past 25 years.

Clive Wearing was a famous musician in his forties when he was stricken with encephalitis. When his encephalitis went away, Clive was left with the worst case scenario; an inability to form new memories and a loss of all previous memories. The loss of his past life, called retrograde amnesia, left him with no recollection of anything except for his wife and music. His new life was something that had never been documented before. It seemed as if every minute or so, to Clive, a new life began. In an attempt to document his life, he started to keep a journal. Most of the journal is filled with sentences like "I am just now awake" that are crossed out and re-written every few minutes. Oliver Sacks gives a great description of Clive Wearing here.

From Clive's injury, he had to move into a house that could take care of him full time. The only happiness in his day is when his wife appears and he gets to see her, although he thinks he has not seen her in years. When she steps out of the room and returns, he is surprised at her visit once again. And for Clive, this surprise happens every minute of every day.

As much as I can try to describe Clive and his life, the effect of his encephalitis is much more devastating when viewing him. Here are some videos of Clive throughout the years:
Video 1
Video 2
Video 3

I hope that you were able to look at these case studies and learn something about the field of cognitive science that you previously didn't know. Thank you for reading!

Monday, October 11, 2010

The American Crowbar Case

Could you imagine what it would be like if you had no filter on your speech? If you constantly spoke your mind? Or if you were unable to decide anything? The man I will discuss today is an example of what can happen to people when the brain suffers irreparable damage.

Phineas Gage might be the case study of all case studies. He was a railroad worker in the 1840s that was seriously injured in a railroad accident. Blasting powder exploded near him, causing his tamping iron to fly towards him and enter his skull through his eye, exiting from the top of his skull, landing many feet away. Amazingly, within a few minutes of the accident, Gage was upright and conscious, although seriously injured. Gage suffered severe brain damage, although in the 1800s it was hard for doctors to understand just how much had been affected.


This is an image of where the iron went through Gage's skull.

Gage's left frontal lobe took the brunt of the damage from the iron. This damage dramatically changed his life, personality, and emotions. His doctor reported, "He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom), manifesting but little deference for his fellows, impatient of restraint or advice when it conflicts with his desires, at times pertinaciously obstinate, yet capricious and vacillating, devising many plans of future operations, which are no sooner arranged than they are abandoned in turn for others appearing more feasible." According to some reports, Gage's boss would not hire him after the accident due to his complete change in personality. Gage's injury laid the groundwork for the discovery that the frontal lobe played a major role in personality.

This article gives an interesting account of how the first picture of Gage was found.

Next blog I will talk about a man also suffering from brain damage that plays a very different role in his day-to-day life.

Monday, October 4, 2010

To speak or not to speak

As you can imagine, speech is a very important part of our day-to-day lives. Speech is a very complex process that can be affected by many different things. In this blog entry, I will describe a few case studies relating to speech.

First, to discuss Tan. Paul Broca was a researcher that discovered a patient who, for an unknown reason, could only say the word "tan." He could understand whatever Broca said to him, but the only thing he could respond with was "tan." Upon Tan's death, Broca looked at his brain and found a lesion in the left cerebral hemisphere. This finding determined the location of the speech production in the brain, now called Broca's area. Here are two videos showing Broca's aphasia:
Video 1
Video 2
As you can tell from these videos, people suffering from Broca's aphasia can understand conversation but are unable to produce the responses that they would like to. There is a syndrome that is also related to speech called Wernicke's aphasia in which a person's speech is preserved, but they are unable to understand what they're saying. Their speech seems to be mindless rambling, but the patient believes that what they are saying makes sense. Here is a video showing Wernicke's aphasia:
Video
As you can see in this video, the man believes that he is speaking coherently, but only producing nonsense words.
Here is an image showing where Broca's and Wernicke's areas are located in the brain:


The other case study I will discuss in this blog entry is that of Genie. When Genie was discovered, she was a 13 year old girl that had lived her whole life sheltered in one room. Her family severely abused her and rarely, rarely spent time with her. She was never taught to speak, and was often reprimanded when she attempted to. Due to this, she never developed language abilities. Her lack of ability was interesting to linguists and by studying her they made strides in understanding the development of speech in children and the critical period, the idea that learning language is linked to age. She was able to develop some sort of speech, but it is limited at best. She appeared to be incapable of stringing words together to form sentences, even though testing showed that she was highly capable in right-brained activities. Due to her isolated childhood, she was incapable of developing language as normal children do. In 2001, a film was released based on Genie's life; Mockingbird Don't Sing.

Next blog, I'll tell you about two other effects that brain damage can have on a person.