A metodu ġdid ta 'evalwazzjoni pazjenti neurokirurġiċi jipprovdi ħarsa frisk lejn kif il-moħħ jipproduċi diskors
Riċerkaturi fl-U.S. żviluppaw teknika ġdida u mtejba għall-immappjar u l-protezzjoni funzjoni tal-moħħ fil-pazjenti konxji dwar li ssirilhom newrokirurġija - permezz ta 'tkessiħ żgħar, reġjuni moħħ lokalizzati temporanjament jinterrompu ħidmiet tagħhom u mappa l-oqsma meħtieġa għall-formazzjoni kelma u l-ħin tad-diskors. Dawn jiddeskrivu l-metodu tagħhom, u spjega kif l użah biex tinvestiga l-mekkaniżmi moħħ sottostanti għall-produzzjoni tal-lingwa mitkellma, fi studju ġdid kemm ippubblikat fil-ġurnal neuron.
Stejjer dwar in-nies li jibqgħu imqajjem waqt kirurġija tal-moħħ jidhru regolarment fil-midja tal-massa. Fl 2008, per eżempju, ħwienet aħbarijiet multipli rrappurtat li leġġendarju Bluegrass mużiċist Eddie Adcock mhux biss baqa konxja, iżda wkoll lagħbu Banjo tiegħu, matul perjodu ta 'u nofs operazzjoni biex tiġi kkurata rogħda idejn. U l-aħħar Diċembru, kien hemm rapporti simili dwar il-mużiċist jazz Spanjola Carlos Aguilera, li lagħbu saxophone tiegħu matul operazzjoni 12 siegħa biex tneħħi tumur tal-moħħ.
Dawn il-proċeduri huma sikwit deskritta bħala "zaskakuje,"" Rivoluzzjonarju,"u, kultant, "Mirakuluża." Fil-fatt, kirurgi kienu qed joperaw fuq l-imħuħ tal-pazjenti konxja għal kważi mitt sena: Il-metodu kien żviluppat fl-1920s mill-newrokirurgu Kanadiż pijunier Wilder Penfield, bħala mod ta 'jsib l-tessut tal-moħħ anormali li jikkawżaw aċċessjonijiet epilettiċi.
Penfield used electrodes to stimulate the surface of his patients’ brains, and deliberately kept them awake during surgery so that they could report the effects of the stimulation back to him. By stimulating the areas around the abnormal tissue, he could identify the tissue causing the seizures while also determining which of the surrounding areas are crucial for important functions like speech and movement. Dan il-mod, he could remove the abnormal tissue without causing any collateral damage.
Penfield’s method of cortical stimulation is still used widely today but, somewhat ironically, can itself trigger epileptic seizures. The new method carries no such risk. Developed by Michael Long of New York University’s Langone Medical Center and his colleagues, it builds on an earlier method that used cooling probes to study the brain circuitry responsible for song production in zebra finches.
Long and his colleagues used a similar cooling device on 16 patients being evaluated for neurosurgical operations to treat their drug-resistant epilepsy. With the patients under local anaesthetic, the researchers used the device to cool 42 discrete brain regions, all of which have been previously implicated in speech production, by about 10°C each. Sadanittant, the patients were asked to recite the days of the week, or a simple string of numbers, so that their speech function could be assessed while each region was cooled.
Cooling interrupts cellular activity, and in some cases, the researchers found that it interfered with the patients’ ability to speak, slowing and blurring their speech. This effect was only temporary, however – brain function returned to normal immediately after the cooling device was removed from the brain, and all 16 patients subsequently recovered from their operations without any undesired side effects or other complications.
The results confirm earlier findings that the brain areas involved in speech production are mostly confined to the left hemisphere, and they also provide new insights into how the brain produces speech. speċifikament, cooling a specific part of the left motor cortex altered the quality of the patients’ speech, whereas cooling of Broca’s Area in the left temporal lobe altered the timing of their speech.
These results shows that the motor cortex directs the muscle movements in the lips and tongue that are required for articulating speech, whereas Broca’s Area is needed for executing these movements in their proper sequence.
“This study confirms that cooling is a safe and effective means of protecting important brain centers during neurosurgery," jgħid Long. "[hija] also represent[i] a major advance in the understanding of the roles played by the areas of the brain that enable us to form words.”
Long, M. A., et al. (2016). Functional Segregation of Cortical Regions Underlying Speech Timing and Articulation. neuron 89: 1–7. DOI: 10.1016/j.neuron.2016.01.032 [Abstract]
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