A neural basis for unique hues?

pathogens. Experimental studies crossing the presence/absence of the bacteria with the presence/absence of a specialized garden pathogen — a fungus in the genus Escovopsis — have shown that ants with antibiotic-producing bacteria are better able to protect their fungal gardens from disease. These studies are among the best evidence that at least some antibiotics suppress infections in nature. The ant–fungus–bacteria mutualism is an ancient system whose evolutionary histories can be deduced by traditional molecular phylogenetic studies. Once these histories have been established and the associated antibiotics have been identified, there will be a wealth of data to trace both the evolution of these small molecules and their function. These studies could also reveal how the ant-bacteria system has maintained itself over tens of millions of years without running out of antibiotics to combat the inevitable development of antibiotic resistance by their microbial pathogens. In short, we can learn a lot from bugs — both the six-legged and microbial varieties. hue circle, they show the number of cells that are maximally excited by that hue. There are three peaks in the histogram: one (the largest) falls close to unique red and another falls close to unique blue, while the third (less well-defined) lies in the yellow-green region. In fact, however, if the stimuli used in the experiment are plotted in a physiological color space, they form not a circle but an obtuse triangle. The peaks identified by Stoughton and Conway [4] fall at the apices of this triangle. Because these stimuli maximize the ratios of cone signals, they would maximally excite cells earlier in the visual system. So Stoughton and Conway's polar plot does not in itself show that cells of the posterior inferior temporal cortex represent unique hues, nor that they differ qualitatively in their behavior from chromatic cells at an earlier level. The stimuli were presented to the monkey on a CRT and the individual chromaticities were obtained by The four perceptually simple colors — red, green, yellow and blue — are a challenge to neuroscience, because no one has found cortical cells that represent color in terms of these 'unique hues' [1]. The chromatically selective cells at early stages of the primate visual system do not map on to the unique hues [2,3]. Recently, however, Stoughton and Conway [4] have reported that the peak sensitivities of color cells in posterior inferior temporal cortex do cluster near the unique …