משתמש:ליםלים/ארגז חול

מתוך ויקיפדיה, האנציקלופדיה החופשית

פינאס פ. גייג'אנגלית: Phineas P. Gage ) ‏ (1823 - 21 במאי 1860) היה פועל רכבת שעבד בהרכבת מסילות ברזל. הוא התפרסם לאחר שבעת עבודה סבל מפגיעה טראומטית במוח כאשר מוט ברזל חדר לגולגלתו, ועבר דרכה אל המוח, כאשר הוא פוגע באונה המצחית. פגיעה זו כפי הנראה שינתה את אופיו בצורה משמעותית, עד שחבריו אמרו עליו "הוא אינו גייג' יותר".
המקרה של גייג' הפך למפורסם בציבור ובקהילה המדעית של אותו הזמן, והוביל לשינוים בתפיסה המדעית של חלוקת המוח ותפקודו, באשר לרגשות, שליטה בדחפים, ואישיות.המקרה של גייג' היה אחת העדויות הראשונות שהצביעו על כך שנזק לאונה המצחית יכול לשנות היבטים של האישיות, ולפגוע ביכולת להתנהגות החברתית הנאותה.

פציעתו של גייג'[עריכת קוד מקור | עריכה]

On September 13, 1848, Phineas P. Gage was working outside the small town of Cavendish, Vermont on the construction of a railroad track where he was employed as a foreman. One of his duties involved filling the hole with gunpowder, adding a fuse, and then packing in sand with the aid of a large tamping iron. Gage was momentarily distracted and forgot to pour the sand into one hole. Thus, when he went to tamp the sand down, the tamping iron sparked against the rock and ignited the gunpowder, causing the iron to be blown through Gage's head with such force that it landed almost thirty yards (27 meters) behind him.

The three foot (1 m) long tamping iron with a diameter of 1.25 inches (3.2 cm) weighing thirteen and a half pounds (6.12 kg) entered his skull below his left cheek bone and exited after passing through the anterior frontal cortex and white matter. Whether the lesion involved both frontal lobes, or was limited only to the left side, remains a matter of controversy. Remarkably, after such a traumatic accident, Gage regained consciousness within a few minutes, was able to speak, and survived a 45-minute ride back to his boarding house while sitting in a cart.

As the doctor arrived, he was reportedly conscious, and had a regular pulse of about 60 beats per minute; however, he was getting exhausted from the hemorrhage, which was very profuse.

His left pupil was still reacting to direct light (and stayed that way for the following 10 days), which indicates that the left optic and oculomotor nerves were still functioning, supporting the hypothesis that the tamping iron must have passed laterally to the left optic nerve. After a seemingly complete recovery from such a serious injury, Gage was soon back at work.

While studies by Hanna Damasio and colleagues suggested a bilateral damage to the medial frontal lobes,[1] a recent study by Ratiu and colleagues based on a CT scan of Gage's skull suggests that the extent of Gage's brain injury must have been more limited than previously thought.[2]

In the view of modern medical science, a bilateral damage of the frontal brain by a projectile measuring 1.25 inches in diameter and weighing thirteen pounds, would unlikely be compatible with survival, since this would imply an extensive damage to vital vascular structures, such as the superior sagittal sinus (however, the rod did not emerge exactly in the midline, and may have missed the sinus by passing beneath it). Nevertheless, Gage survived the traumatic event and complications by a fungal infection and over-exercise. Gage later reportedly developed personality changes.