التفاصيل البيبلوغرافية
| العنوان: |
When the Brain Changes Its Mind: Flexibility of Action Selection in Instructed and Free Choices |
| المؤلفون: |
Fleming, SM, Mars, RB, Gladwin, TE, Haggard, P |
| المصدر: |
CEREB CORTEX , 19 (10) 2352 - 2360. (2009) |
| بيانات النشر: |
OXFORD UNIV PRESS INC |
| سنة النشر: |
2009 |
| مصطلحات موضوعية: |
action selection, event-related potential, motor preparation, voluntary action, POSTERIOR PARIETAL CORTEX, EXTERNALLY TRIGGERED MOVEMENTS, POSITRON-EMISSION-TOMOGRAPHY, MEDIAL FRONTAL-CORTEX, CEREBRAL-BLOOD-FLOW, PREMOTOR CORTEX, RESPONSE SELECTION, PREFRONTAL CORTEX, ATTENTION, psy, socio |
| الوصف: |
The neural mechanisms underlying the selection and initiation of voluntary actions in the absence of external instructions are poorly understood. These mechanisms are usually investigated using a paradigm where different movement choices are self-generated by a participant on each trial. These "free choices" are compared with "instructed choices," in which a stimulus informs subjects which action to make on each trial. Here, we introduce a novel paradigm to investigate these modes of action selection, by measuring brain processes evoked by an instruction to either reverse or maintain free and instructed choices in the period before a "go" signal. An unpredictable instruction to change a response plan had different effects on free and instructed choices. In instructed trials, change cues evoked a larger P300 than no-change cues, leading to a significant interaction of choice and change condition. Free-choice trials displayed a trend toward the opposite pattern. These results suggest a difference between updating of free and instructed action choices. We propose a theoretical framework for internally generated action in which representations of alternative actions remain available until a late stage in motor preparation. This framework emphasizes the high modifiability of voluntary action. |
| نوع الوثيقة: |
article in journal/newspaper |
| اللغة: |
unknown |
| العلاقة: |
http://discovery.ucl.ac.uk/178946Test/ |
| الإتاحة: |
http://discovery.ucl.ac.uk/178946Test/ |
| حقوق: |
undefined |
| رقم الانضمام: |
edsbas.14ACFAF7 |
| قاعدة البيانات: |
BASE |
