Online research in philosophy

We investigated binocular rivalry in the twocerebral hemispheres of callosotomized(split-brain) observers. We found that rivalryoccurs for complex stimuli in split-brainobservers, and that it is similar in the twohemispheres. This poses difficulties for twotheories of rivalry: (1) that rivalry occursbecause of switching of activity between thetwo hemispheres, and (2) that rivalry iscontrolled by a structure in the rightfrontoparietal cortex. Instead, similar rivalryfrom the two hemispheres is consistent with atheory that its mechanism is low in the visualsystem, at which each hemisphere conducts (...) asimilar analysis of its half of visual space. (shrink)

Different hypotheses about the mechanisms underlying working memory lead to different predictions about working memory capacity when information is distributed across the two hemispheres. We present preliminary data suggesting that memory scanning time (a parameter often associated with working memory capacity) varies depending on how information is subdivided across hemispheres. The data are consistent with a distributed model of working memory.

Corballis suggests that fully vocal communication was invented by modern humans between 170,000 and 50,000 years ago. Because this new form of communication did not require hand gestures, he wondered whether this may have facilitated the development of lithic manufacture. I cast doubt on this interesting notion but offer an enhanced version that may have more potential.