. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. COMPUTATION IN CEPHALOPOD LEARNING SYSTEM 201 Feature detectors Basal lobes Attack Taste Medsupfr. Vertical Subvert ic al Magno cellular Retreat Figure 1. Scheme to show alternative pathways from the visual fea- ture detectors of an octopus. There are output pathways for attack or retreat. A third pathway leads to the four matrices of the vertical lobe system. Here particular patterns of visual signals are combined with those of taste to increase the future tendency to attack, or with signals of pain to reduce it. the respon
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. COMPUTATION IN CEPHALOPOD LEARNING SYSTEM 201 Feature detectors Basal lobes Attack Taste Medsupfr. Vertical Subvert ic al Magno cellular Retreat Figure 1. Scheme to show alternative pathways from the visual fea- ture detectors of an octopus. There are output pathways for attack or retreat. A third pathway leads to the four matrices of the vertical lobe system. Here particular patterns of visual signals are combined with those of taste to increase the future tendency to attack, or with signals of pain to reduce it. the response of the system as a categorizer climbs over repeated iterations" (Rolls, 1990). In autocorrelation networks, such as the CAi cells (Fig. 2), the preferred pathways are reinforced by mutu- ally strengthening each other. In this case, the cells of the matrix have collaterals that feed back to their own inputs. These recurrent synapses follow the Hebb rule so that "any strongly activated cell or set of cells becomes linked by strengthened synapses with any other conjunctively activated cell or set of cells" (Rolls, 1990). As a result, during recall "presentation of even part of the original pattern . . comes to elicit the firing of the whole set of cells that were originally conjunctively ; In the hippocampus, this result is achieved by the col- laterals of the CA3 cells, which reactivate the dendrites of their own and a large number of other CA, cells. It may be that in cephalopods a similar effect is achieved by pass- ing the signals through a series of lobes, each serving as a matrix whose output may be returned to a previous member of the series (Fig. 3). The functioning of any such matrix system depends on the particular anatomical ar- rangements and details of synaptic functioning and its alteration with use. We do not know enough about such factors in cephalopods to be able to specify precisely how they operate. However, the system is si
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
