Deafferentation Mammals

The classical approach, advocated by the organ s discoverer (pp. 94), seeks to prevent any transmission along the afferent pathway, then to analyse the resulting deficits, if any. Adaptiveness in the AOS — such as its dependence on experiential variables — has also to be recognised and evaluated (Wysocki, 1986 Clancy et al., 1988). The aim is to disentangle the various contributions of the AOS and MOS to the 

Prevention of access is the least intrusive method since it need not have any irreversible consequences for the afferent pathway. The common entrance to both olfactory systems in newts is easily closed-off by plugging the nostrils (Kikuyama et al., 1997). A potentially reversible method threaded plugs into the NP canal of cats via the nasal cavity (Verbeme, 1980). This procedure produced a slight effect on male chemoinvestigation of urine and or scent marks. The advantages of avoiding tissue disturbance then, have to be offset by the lack of any estimate of the effectiveness of the blockade, especially if reversible. Tissue cement injections into the N-Pd can be applied to the larger 

Extirpation of the entire VN complex (VN-x) is an effective and informative approach applied largely to mammals. A palatal incision, followed by cautery or dissection of the capsule, usually removes all 

An early effort using this approach in Guinea-pigs reported variable results — attributable to incomplete nerve sectioning (Planel, 1953). Sectioning procedures may also produce some unwanted effects as intracranial nerve section will remove part of the animal s N. terminalis sensory capability (Devitsina and Cherova, 1992). 

The equivalent procedure for the main olfactory epithelial sheet (MOEx) is chemical ablation by treatment with (5%) zinc sulphate solution. The adoption of this approach was determined by practical anatomy, given the inevitably partial, let alone traumatic, results of cutting/scraping epithelia from the intricately folded sensory surfaces (Negus, 1958). 

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