Alsof de NASA samen met universitaire astronomen zouden uitbazuinen dat ze
God in het heelal hebben ontdekt, zo publiceerden neuro-onderzoekers van de Johns
Hopkins University dat ze de vrije wil in het brein hebben gezien. Leon
Kuunders wees me op hun persbericht: “What Free Will Looks Like in the Brain” [cf.] en hoorde hen a.h.w. roepen: Ladies and Gentlemen,
we've got him.
Het ‘glasheldere’ Abstract neem ik over:
The neural substrates of volition
have long tantalized philosophers and scientists. Over the past few decades,
researchers have employed increasingly sophisticated technology to investigate
this issue, but many studies have been limited considerably by their reliance
on intrusive experimental procedures (e.g., abrupt instructional cues),
measures of brain activity contaminated by overt behavior, or introspective
self-report techniques of questionable validity. Here, we used multivoxel
pattern time-course analysis of functional magnetic resonance imaging data to
index voluntary, covert perceptual acts—shifts of visuospatial attention—in the
absence of instructional cues, overt behavioral indices, and self-report. We
found that these self-generated, voluntary attention shifts were time-locked to
activity in the medial superior parietal lobule, supporting the hypothesis that
this brain region is engaged in voluntary attentional reconfiguration.
Self-generated attention shifts were also time-locked to activity in the basal
ganglia, a novel finding that motivates further research into the role of the
basal ganglia in acts of volition. Remarkably, prior to self-generated shifts
of attention, we observed early and selective increases in the activation of
medial frontal (dorsal anterior cingulate) and lateral prefrontal (right middle
frontal gyrus) cortex—activity that likely reflects processing related to the
intention or preparation to reorient attention. These findings, which extend
recent evidence on freely chosen motor movements, suggest that dorsal anterior
cingulate and lateral prefrontal cortices play key roles in both overt and
covert acts of volition, and may constitute core components of a brain network
underlying the will to attend.
Het is dezelfde universiteit waar de Spinoza scholar Yitzhak
Melamed hoogleraar filosofie is. De neurowetenschappers zouden eens bij hem
langs kunnen gaan om zich te laten uitleggen wat Spinoza eigenlijk bedoelde met
te stellen en te beargumenteren dat de vrije wil in ons niet bestaat. Uiteraard
hebben we willingen en verlangens en maken we keuzen, maar niet vanuit een
onveroorzaakt wilsvermogen (dat we niet hebben, ook niet in het brein).
[Illustratie van neurosciencenews.com aangepast aan blog-maten]
