Overview and Basic Principles. Physiological and Psychological Foundations of Sensory Function. Principles of Good Practise. Discrimination Testing. Discrimination Theories and Advanced Topics. Threshold Testing as a Special Case of Discrimination Tests. Scaling Models and Numerical Measurement. Time Intensity Methods. Context Effects and Biases. Descriptive Analysis. Texture. Color and Appearance Measurement. Acceptance and Preference Testing - Laboratory Applications. Acceptance and Preference Testing - Consumer Tests Outside the Laboratory. Qualitative Research Methods. Data Relationships & Multivariate Applications. Strategic Research. Overview and Recap. Statistical Appendices.

Sensory Evaluation of Food: Principles and Practices

During the past 20 years, research in the behavioral sciences has become increasingly sophisticated. New findings concerning the brain and behavior have forced upon us the unpleasant necessity of reexamining our models. Concepts once useful, such as "the unconscious," "regression," and "motivation," no longer serve to adequately encompass the data. Ashby is a representative of this new order of sophistication in research, as he proceeds to investigate the problem of the brain's orderliness. He accepts, as fact, that the nervous system behaves adaptively and assumes that it is, in its essentials, mechanistic. These two data are approached as not irreconcilable. From this point, he proceeds to examine dynamic systems from the standpoint of rigorous scientific —dominantly mathematical—logic until he has evolved a theoretical counterpart of brain functioning. He then builds and experiments with a prototype electronic model, which he names the "Homeostat," and tests various aspects of his theories of

Design for a Brain

Production and characteristics of protein hydrolysates from capelin (Mallotus villosus)

Abnormalities in functional connectivity between brain areas have been postulated as an important pathophysiological mechanism underlying schizophrenia. In particular, macroscopic measurements of brain activity in patients suggest that functional connectivity between the frontal and temporal lobes may be altered. However, it remains unclear whether such dysconnectivity relates to the aetiology of the illness, and how it is manifested in the activity of neural circuits. Because schizophrenia has a strong genetic component, animal models of genetic risk factors are likely to aid our understanding of the pathogenesis and pathophysiology of the disease. Here we study Df(16)A(+/-) mice, which model a microdeletion on human chromosome 22 (22q11.2) that constitutes one of the largest known genetic risk factors for schizophrenia. To examine functional connectivity in these mice, we measured the synchronization of neural activity between the hippocampus and the prefrontal cortex during the performance of a task requiring working memory, which is one of the cognitive functions disrupted in the disease. In wild-type mice, hippocampal-prefrontal synchrony increased during working memory performance, consistent with previous reports in rats. Df(16)A(+/-) mice, which are impaired in the acquisition of the task, showed drastically reduced synchrony, measured both by phase-locking of prefrontal cells to hippocampal theta oscillations and by coherence of prefrontal and hippocampal local field potentials. Furthermore, the magnitude of hippocampal-prefrontal coherence at the onset of training could be used to predict the time it took the Df(16)A(+/-) mice to learn the task and increased more slowly during task acquisition. These data suggest how the deficits in functional connectivity observed in patients with schizophrenia may be realized at the single-neuron level. Our findings further suggest that impaired long-range synchrony of neural activity is one consequence of the 22q11.2 deletion and may be a fundamental component of the pathophysiology underlying schizophrenia.

/pdf/impaired-hippocampal-prefrontal-synchrony-in-a-genetic-mouse-50neolql7i.pdf

Impaired hippocampal–prefrontal synchrony in a genetic mouse model of schizophrenia

The color, flavor, texture, and the nutritional value of fresh-cut fruit and vegetable products are factors critical to consumer acceptance and the success of these products. In this chapter, desirable and undesirable quality attributes of fresh-cut fruit and vegetable products are reviewed. Both instrumental and sensory measurements for determining these critical quality attributes are discussed. The advantages and disadvantages of sensory and instrumental quality measurements are described. A review of typical unit operations involved in the production of fresh-cut products is presented. The effects of fresh-cut processing techniques and treatments on sensory quality, including the appearance, texture, flavor (taste and aroma) of vegetables, and fruits are detailed.

/pdf/color-flavor-texture-and-nutritional-quality-of-fresh-cut-4peev5sav8.pdf

Color, Flavor, Texture, and Nutritional Quality of Fresh-Cut Fruits and Vegetables: Desirable Levels, Instrumental and Sensory Measurement, and the Effects of Processing

Olfactory adaptation and recovery to methyl isobutyl ketone at a concentration 10 times the absolute detection threshold (It
 o) was intensively studied in two human Ss. A combined psychophysical procedure was used that allowed comparisons of changes in threshold (It) with changes in the subjective intensity of suprathreshold stimuli. Information was also obtained on the effect of the adapting stimulus on the psychophysical power function for this odorant. A threshold detection procedure was used to estimate changes in It; an unstructured magnitude-estimation procedure was used to monitor changes in the subjective intensity of suprathreshold stimuli and the psychophysical power function. The data provided additional information on the behavioral course of olfactory adaptation and recovery and suggested that this combined method can be used profitably for further investigations of this kind. Complementary to the work of Cain and Engen (1969), the results suggested an increase in the exponent of the power function with increasing adaptation.

https://link.springer.com/content/pdf/10.3758/BF03212603.pdf

Changes in absolute detection threshold and in subjective intensity of suprathreshold stimuli during olfactory adaptation and recovery

SENSORY EVALUATION | Descriptive Analysis

Publisher Summary This chapter focuses on test strategy in relation to experimental design, taking into account the request for assistance, product criteria, and the impact of psychological errors on response behavior. Experimental design is also considered with a sensory orientation. The chapter focuses on test strategy as it is applied to the individual request for assistance. The overall goal is to formulate and implement a test plan that will satisfy the stated objective. Specific issues that need to be considered before a plan is completed, and the test implemented are in addition to test priority, objective, and product identification and availability. Test strategy should include the possibility of an initial rejection of a request if the products are inappropriate or the basis for the request cannot be justified. Sensory evaluation uses statistics to determine whether the responses from a group of subjects are sufficiently similar or represent a random occurrence. The chapter also discusses the statistical issues that sensory professionals consider while determining the most appropriate experimental design and analysis for a particular problem.

Test Strategy and the Design of Experiments

Publisher Summary
This chapter discusses a sensory evaluation model for measuring product acceptance. Sensory acceptance represents the third and final phase of test resources along with discrimination and descriptive analysis tests. As a resource, it provides continuity between the controlled laboratory environment and the typical product use situation, such as home, restaurant, and so forth. The types of sensory acceptance tests include the laboratory, central location, and home-use. All of these test types follow accepted sensory evaluation procedures and practices. The sensory acceptance test is a very cost-effective resource and plays a major role in the development of successful products. The chapter discusses two methods to measure preference and acceptance—the paired-comparison test and the nine-point hedonic scale. The subjects participating in a sensory acceptance test should be qualified based on typical demographic and usage criteria or preference scores from survey data. The chapter also discusses the relationship between the sensory acceptance and the larger-scale marketing research models, and the role of the sensory acceptance model and its responsibilities in the product evaluation.

Herbert Stone

Papers

Changes in absolute detection threshold and in subjective intensity of suprathreshold stimuli during olfactory adaptation and recovery

SENSORY EVALUATION | Descriptive Analysis

Test Strategy and the Design of Experiments

7 – Affective Testing

Chapter 6 – Descriptive Analysis