Central discrimination

Fig. 7.10(c)]. These ewes allowed both alien lambs and their own lambs to suckle (Booth et al., 2000). Since MOE-x still permitted own/ alien discrimination, it appears that lamb acceptance is dependent upon the ability of the AOS to distinguish familiarity. The discrepancies may derive from technique or strain differences. The combined, possibly central, effects of complete deafferentation are perhaps necessary to disrupt such important responses. Whether, for instance, multiparous rats could be at all resistant to such treatments has not been tested. 

Furthermore, the pattern structures in a representation space formed from raw input data are not necessarily linearly separable. A central issue, then, is feature extraction to transform the representation of observable features into some new representation in which the pattern classes are linearly separable. Since many practical problems are not linearly separable (Minsky and Papert, 1969), use of linear discriminant methods is especially dependent on feature extraction. 

Ukai M., Mori E., Kameyama T. Effects of centrally administered neuropeptides on discriminative stimulus properties of cocaine in the rat. Pharmacol. Biochem. Behav. 51 705, 1995. 

The VolSurf method was used to produce molecular descriptors, and PLS discriminant analysis (DA) was applied. The statistical model showed two significant latent variables after cross-validation. The 2D PLS score model offers a discrimination between the permeable and less permeable compounds. When the spectrum color is active (Fig. 17.2), red points refer to high permeability, whereas blue points indicate low permeability. There is a region in the central part of the plot with both red and blue compounds. In this region, and in between the two continuous lines, the permeability prediction is less reliable. The permeability model... 

In our initial use of VIRS methods, we have chosen a diverse set of projects. These include epithermal-style precious metal mineralization (eastern and central Newfoundland), mesothermal gold mineralization (Central Newfoundland), syngenetic VMS mineralization and related alteration (Central Newfoundland), porphyry-style Mo-Cu mineralization (southern Newfoundland) and uranium mineralization in the Central Mineral Belt of Labrador. Space does not permit detailed discussion of results, but in all cases we were able to recognize distinctive alteration species and document their distribution. In some cases, results provided surprises, eg., the recognition of topaz in quartz-alunite alteration and possible Li-rich micas in VMS alteration influenced by magmatic fluids. In some cases, the resolution of species in mixed assemblages proved to be difficult, but the overall spectral patterns could still be used to discriminate alteration facies and demonstrate their superposition. 

FIG. 2. Comparison of the discriminative stimulus properties of LSD, morphine, and methadone when injected into the DRN of the rat. Rats were trained to discriminate LSD (120 ng/kg s.c.), cannulae implanted, and generalization from peripheral to central administration determined over a variety of doses of each drug. (Redrawn from the research of Rosecrans and Glennon, ref. 59.) A, I.C. saline, , I.C. morphine in morphine trained rats, O, I.C. saline, , I.C. LSD in LSD trained rats, , I.C. saline, , I.C. methadone in methadone trained rats. 

Minnema, D. J. (1981) An examination of the central nervous system mechanisms underlying discriminative stimulus properties of lysergic acid diethylamide. Unpublished doctoral dissertation, Virginia Commonwealth University, Richmond, Virginia. 

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