Sensory testing capability

The use of computer tools with an old population must be carefully considered as many young seniors master computers perfectly and will be totally capable of performing the sensory tests with this type of tool (probably they will be even more so in the future). Yet this is not the case for all aged people, and a paper questionnaire should be systematically available. In the future, tools specifically developed for tablets may get around some difficulties, as far as they are developed for people with visual impairment. Finally, some elderly people may not be able to write (which frequently happens in nursing homes). In that case, an experimenter should take notes of the participant s answers without influencing him. 

Routine procedures to assay the extent of oxidation in lipids and lipid-containing foods should be simple, reliable and sensitive. Results from routine procedures should ideally correlate well with results obtained from sensory taste panels. St. Angelo (1996) has described volatile compound profiles formed during lipid oxidation in different groups of food products. However, because of the complexity of lipid oxidation, no single test can be equally useful at all stages of the oxidative process. The methods should be capable of detecting autoxidation before the onset of off-flavor. This is particularly true in the case of milk products where a low level of oxidation can lead to off-flavor. 

An elaborate study by Ramer etal. (2000) finally documented a functional regeneration of sensory axon (Ramer et al., 2000). Not only were specific behavioral tests corresponding to the regenerated fiber phenotypes used, but they also confirmed their findings by reinjury of the regenerated fibers to demonstrate their capability for participation in functional recovery. 

Assessments of motor function are often included in the neuropsychological test batteries utilized in occupational exposure studies. Typically, these tend to be relatively simple measures of motor capabilities, probably for two reasons. The first is that the inclusion of vigilance tasks such as those described previously depends on motor coordination in addition to sensory capabilities therefore, toxicant-induced changes in such performances may already be indicative of motor impairment. This can then be pursued by inclusion of some additional and more direct assessments of motor function in the battery. The second reason relates to logistical reasons and practicalities. Test batteries such as the WHO Neurobehavioral Core Test Battery and the NFS are typically taken to the site where measurements of subjects are to be made. Thus, portability is a major consideration, and more complex assessments of motor function would incur greater equipment needs. Since the purpose of these batteries is generally to screen for adverse effects, studies providing more precise delineations of affected functions can be pursued at a later time. 

Delayed neurotoxicity results from degeneration of the axons followed by demyelination (14,15,23). Clinical manifestation includes sensory disturbances, ataxia, weakness, muscle twitching and, in severe cases, complete flaccid paralysis ( 15). A fair number of organophosphate compounds are capable of inducing delayed neurotoxicity. Of the 250 organophosphates (not all pesticides) tested for delayed neurotoxicity in chickens, 47% (117 chemicals) showed positive responses (23). Notable examples of pesticides which possess this neurotoxicity are leptophos, EPN, merphos, dichlorvos, and... 

The availabihty of a pool of qualified consumers also allows for testing in a typical use situation such as a home-use test This capability enhances the value of a sensory capability. Here too its goal is to provide support for a product before larger scale testing. 

Rigorous assessments of sensory and motor function ai also absent. Conventional clinical techniques are unlikely to detect the subtle deficits said to arise fhjm moderately elevated lead exposures. Visual science, for example, now provides assessment tools, based on engineering models of the visual system, capable of probing the boundaries of visual function. Motor function also demands more refined procedures than the industrial screening tests or measures of motor conduction velocity used by some investigators. Evaluation of fine motor control and perceptu ll-motor performance requires an engineering cinalysis similar to those applied to studies of Parkinsonism. ... 

This first study highlights several points that need to be taken into account in any sensory analysis based on olfactory tasks. Thus gender is shown to be able to influence scores in threshold and identification tasks. Cultural origin may influence scores in suprathreshold detection and identification tasks. Scores in identification tasks may also be influenced by healthy aging when corrected by detection measures. Thus it appears to be important (a) to assess and to check panelists olfactory capabilities regularly and (b) to integrate certain parameters in sensory data processing that reflect the panelists sensory sensitivity and could account for interindividual variance. For this purpose, we developed the European Test of Olfactory Capabilities. 

One way to standardize the sensory abilities of panelists is to use olfactory tests. Some of them, such as the ETOC, have been designed for sensory evaluation purposes in order to provide sensory and cognitive clues to olfactory capability. The test scores could thus usefully be included in the processing of sensory data. The assessment of panelists for olfactory and for other sensory sensitivity may, in part, account for the difference between flavor perception and flavor release, which remains a major challenge in the characterization of flavor compounds. 

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