A psychophysical investigation of binary bitter-compound interactions

The aim of this study was to determine if taste interactions occur when bitter stimuli are mixed. Eight bitter stimuli were employed: denatonium benzoate (DB), quinine-HCl (QHCl), sucrose octaacetate (SOA), urea, L-tryptophan (L-trp), L-phenylalanine (L-phe), ranitidine-HCl, and Tetralone. The first experiment constructed individual psychophysical curves for each subject (n = 19) for each compound to account for individual differences in sensitivities when presenting bitter compounds in experiment 2. Correlation analysis revealed two groupings of bitter compounds at low intensity (1, L-trp, L-phe, and ranitidine; 2, SOA and QHCl), but the correlations within each group decreased as the perceived intensity increased. In experiment 2, intensity ratings and two-alternative forced-choice discrimination tasks showed that bitter compounds generally combine additively in mixture and do not show interactions with a few specific exceptions. The methods employed detected synergy among sweeteners, but could not detect synergy among these eight bitter compounds. In general, the perceived bitterness of these binary bitter-compound mixtures was an additive function of the total bitter-inducing stimuli in the mouth.

Bitterness suppression with zinc sulfate and na-cyclamate: a model of combined peripheral and central neural approaches to flavor modification

Purpose Zinc sulfate is known to inhibit the bitterness of the antimalarial agent quinine [R. S. J. Keast. The effect of zinc on human taste perception. J. Food Sci. 68:1871–1877 (2003)]. In the present work, we investigated whether zinc sulfate would inhibit other bitter-tasting compounds and pharmaceuticals. The utility of zinc as a general bitterness inhibitor is compromised, however, by the fact that it is also a good sweetness inhibitor [R. S. J. Keast, T. Canty, and P. A. S. Breslin. Oral zinc sulfate solutions inhibit sweet taste perception. Chem. Senses 29:513–521 (2004)] and would interfere with the taste of complex formulations. Yet, zinc sulfate does not inhibit the sweetener Na-cyclamate. Thus, we determined whether a mixture of zinc sulfate and Na-cyclamate would be a particularly effective combination for bitterness inhibition (Zn) and masking (cyclamate).

Method We used human taste psychophysical procedures with chemical solutions to assess bitterness blocking.

Results Zinc sulfate significantly inhibited the bitterness of quinine–HCl, Tetralone, and denatonium benzoate (DB) (p < 0.05), but had no significant effect on the bitterness of sucrose octa-acetate, pseudoephedrine (PSE), and dextromethorphan. A second experiment examined the influence of zinc sulfate on bittersweet mixtures. The bitter compounds were DB and PSE, and the sweeteners were sucrose (inhibited by 25 mM zinc sulfate) and Na-cyclamate (not inhibited by zinc sulfate). The combination of zinc sulfate and Na-cyclamate most effectively inhibited DB bitterness (86%) (p < 0.0016), whereas the mixture's inhibition of PSE bitterness was not different from that of Na-cyclamate alone.

Conclusion A combination of Na-cyclamate and zinc sulfate was most effective at inhibiting bitterness. Thus, the combined use of peripheral oral and central cognitive bitterness reduction strategies should be particularly effective for improving the flavor profile of bitter-tasting foods and pharmaceutical formulations.

Assessing financial competence in older adults with cognitive impairment

One common problem brought before Courts and Tribunals in Australia is whether or not someone is able to manage his or her own financial affairs. The problem is that currently in Australia there are no universally agreed upon standards for assessing financial competence. The aim of this study was to examine the reliability and validity of a new measure of financial competence, The Financial Competence Assessment Inventory (FCAI), in assessing financial competency of older adults with a cognitive impairment. The sample comprised 18 older adults with acquired brain injury, 10 adults with schizophrenia, 21 adults with dementia and 27 older adults without cognitive impairment. Ages ranged from 55 to 91. Each participant was individually interviewed using the FCAI. The findings revealed that the FCAI is a reliable and valid assessment tool for assessing financial competence of older adults with different types and levels of cognitive impairment. In particular, the FCAI was able to distinguish between older adults with global brain impairment and older adults with specific brain impairment; and older adults who had a legal administrator and older adults who did not. In addition, using the FCAI it was possible to obtain a profile of participants’ strengths and weaknesses across six domains of financial competence including; everyday financial abilities, financial judgment, estate management, cognitive based financial tasks, debt management, and support resources. The FCAI has the potential to assist clinicians and legal decision-makers regarding ‘least restrictive alternatives’ when financial competence is in question.

Empirical generalisation as an inadequate cognitive scaffold to theoretical generalisation of a more complex concept

The impact of prior learning on new learning is highlighted by the case of Dean, a Year 8 student who developed his own method to find the sum of the interior angles of a polygon without knowing why his method worked. Enriched transcripts and visual displays of the cognitive, social (Dreyfus, Hershkowitz, & Schwarz, 2001) and affective elements (Williams, 2002) of Dean's interrupted abstraction process informed the identification of factors that inhibited Dean's constructing process. It was found Dean possessed an empirical, not theoretical, generalization (Davydov, 1990) about sums of interior angles of triangles that was an inadequate cognitive artifact for constructing the new more complex theoretical generalization. The study suggests use of tasks designed with the opportunity develop assumed knowledge in conjunction with new concepts.

Applications of cognitive theories to children's fire safety education

Children under five have the highest rate of fire-related accidents (Australian Institute of Health and Welfare, 2001). It is therefore essential to develop effective fire safety education programs to prevent casualties due to a fire. At present, there are fire education programs conducted across Australia for primary school children. However, it is vital that these programs get their message across to the children in the most efficient manner to help children retain the information. The present study evaluated the effectiveness of the 'Fire Ed' program conducted in Victoria and assessed the retention of fire safety information in children in preparatory and Grade five levels. The findings suggest that the information is not retained over long periods of time. Suggestions are made to provide fire safety education in line with
theories of cognitive development to make it more effective.

Cost-effectiveness of cognitive-behavioural therapy and drug interventions for major depression

Objective: Antidepressant drugs and cognitive–behavioural therapy (CBT) are effective treatment options for depression and are recommended by clinical practice guidelines. As part of the Assessing Cost-effectiveness – Mental Health project we evaluate the available evidence on costs and benefits of CBT and drugs in the episodic and maintenance treatment of major depression.

Method: The cost-effectiveness is modelled from a health-care perspective as the cost per disability-adjusted life year. Interventions are targeted at people with major depression who currently seek care but receive non-evidence based treatment. Uncertainty in model inputs is tested using Monte Carlo simulation methods.

Results: All interventions for major depression examined have a favourable incremental cost-effectiveness ratio under Australian health service conditions. Bibliotherapy, group CBT, individual CBT by a psychologist on a public salary and tricyclic antidepressants (TCAs) are very cost-effective treatment options falling below $A10 000 per disability-adjusted life year (DALY) even when taking the upper limit of the uncertainty interval into account. Maintenance treatment with selective serotonin re-uptake inhibitors (SSRIs) is the most expensive option (ranging from $A17 000 to $A20 000 per DALY) but still well below $A50 000, which is considered the affordable threshold.

Conclusions: A range of cost-effective interventions for episodes of major depression exists and is currently underutilized. Maintenance treatment strategies are required to significantly reduce the burden of depression, but the cost of long-term drug treatment for the large number of depressed people is high if SSRIs are the drug of choice. Key policy issues with regard to expanded provision of CBT concern the availability of suitably trained providers and the funding mechanisms for therapy in primary care.

Subjective wellbeing as an affective-cognitive construct

The affective content of Subjective Wellbeing (SWB) was investigated in two separate studies. Study 1 involved a representative sample of 478 participants from across Australia aged between 18 and 72 years. This study tested the circumplex model of affect and then determined the minimum set of affects that explain variance in SWB. The model was supported, with most affects congregated around the valence axis. Overall, 64% of the variance in SWB was explained by six Core Affects, indicating that SWB is a highly affective construct. Study 2 tested the relative strength of Core Affect (content, happy and excited), in three separate models of SWB incorporating cognition (seven discrepancies)
and all five factors of personality. Using a sample of 854 participants aged been 18 – 86 years, structural equation modeling was used to compare an affective-cognitive driven model of SWB, with a personality driven model of SWB and a discrepancy driven model of SWB. The results provide support for an affective-cognitive model which explained 90 percent of the variance in SWB. All models confirm that the relationship between SWB, Core Affect and Discrepancies is far stronger than the relationship between personality and SWB. It is proposed that Core Affect and Discrepancies comprise the essence of SWB. Moreover, Core Affect is the driving force behind individual set-point levels in SWB homeostasis.

The prevalence and recognition of major depression among low-level aged care residents with and without cognitive impairment

Previous research has demonstrated a high level of depression in nursing homes. The current study was designed to determine the prevalence of depression, using a structured diagnostic interview, among older people with and without mild-moderate cognitive impairment residing in low-level care facilities. The results demonstrated that, consistent with previous research in nursing homes, 16.9% of older people were diagnosed with major depressive disorder. Less than half of these cases had been detected or treated. Individuals with moderate cognitive impairment were more likely to be depressed, but cognitive impairment did not appear to act as a strong impediment to the detection of depression by general practitioners. A low awareness of their use of antidepressant medications was demonstrated among older people prescribed this treatment, including those with normal cognitive function. Reasons for the poor recognition of depression among older people are discussed.

Understanding informations systems outsourcing success and risks through the lens of cognitive biases

Because outsourcing of information systems (IS) is now widespread, it is generally assumed to be successful. It is also often assumed that outsourcing risks are easily managed. In this paper we adopt an “evidence based management” approach to first test these assumptions through a qualitative metaanalysis of academic studies into IS outsourcing outcomes. Our research reveals a shortage of reliable and valid evidence for outsourcing’s benefits, and for the level of risk involved. We then use data from a series of focus groups to explain the paradox of widespread adoption of a strategy with limited empirical support. These focus groups were interpreted through the lens of research on a
range of cognitive mechanisms and biases that are known to affect decision makers. We conclude that cognitive mechanisms that are likely to affect sourcing decisions include framing biases, cognitive dissonance, attribution error, and the “optimism”, “confirmation”, “disconfirmation” and “overconfidence” biases. Given the shortage of supporting evidence, and the potential for these biases to operate, we argue that researchers need to be more critical in their analysis of reports of the success and risks of IS outsourcing.

The cognitive contexts of beliefs about the healthiness of meat

Objective: The overall aim of this study was to examine a variety of belief and demographic factors that are associated with the perception that meat is intrinsically unhealthy.

Design: State-wide survey (written questionnaire) that included questions on meat and nutrition beliefs, perceived barriers and benefits of vegetarian diets, personal values, number of vegetarian friends and family members, and use and trust of health/nutrition/food information sources.

Setting: South Australia.

Subjects: Six hundred and one randomly selected South Australians and 106 non-randomly selected vegetarians and semi-vegetarians.

Results: For all respondents considered as a group, the most important predictors of the belief that meat is intrinsically unhealthy were the perceived benefits of vegetarian diets (all positive predictors). These included: (1) the perceived links between vegetarianism, peace and increased contentment; (2) animal welfare and environmental benefits; and (3) health benefits. There were differences between different dietary groups however. For non-vegetarians, social concerns about vegetarianism (positive) were most important, followed by health and non-health benefits (positive) of vegetarianism. Red meat appreciation was the strongest (positive) predictor for vegetarians, with health benefits of vegetarianism (positive) and education (negative predictor) also important.

Conclusions: The implications of the findings for health and other issues are discussed. Judgements about the healthiness of meat are likely to be related to moral and environmental beliefs and, for non-vegetarians, to social concerns about vegetarianism, in addition to health beliefs. These need to be considered if any attempts are made to influence meat consumption.

Cognitive behavioural strategies for general practice

Cognitive behavioural strategies (CBS) are circumscribed psychologial skills that can be incorporated into general practice, and need to be distinguished from cognitive behavioural therapy (CBT), a comprehensive therapeutic approach which require more intensive training.  The CBS outlined in this article can be integrated with other behavioural and structured problem solving approaches.

Cost-effectiveness of cognitive behavioural therapy and selective serotonin reuptake inhibitors for major depression in children and adolescents

Objective:
To assess from a health sector perspective the incremental cost-effectiveness of cognitive behavioural therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs) for the treatment of major depressive disorder (MDD) in children and adolescents, compared to ‘current practice’.
Method:
The health benefit is measured as a reduction in disability-adjusted life years (DALYs), based on effect size calculations from meta-analysis of randomised controlled trials. An assessment on second stage filter criteria (‘equity’; ‘strength of evidence’, ‘feasibility’ and ‘acceptability to stakeholders’) is also undertaken to incorporate additional factors that impact on resource allocation decisions. Costs and benefits are tracked for the duration of a new episode of MDD arising in eligible children (age 6–17 years) in the Australian population in the year 2000. Simulation-modelling techniques are used to present a 95% uncertainty interval (UI) around the cost-effectiveness ratios.
Results:
Compared to current practice, CBT by public psychologists is the most costeffective intervention for MDD in children and adolescents at A$9000 per DALY saved (95% UI A$3900 to A$24 000). SSRIs and CBT by other providers are less cost-effective but likely to be less than A$50 000 per DALY saved (> 80% chance). CBT is more effective than SSRIs in children and adolescents, resulting in a greater total health benefit (DALYs saved) than could be achieved with SSRIs. Issues that require attention for the CBT intervention include equity concerns, ensuring an adequate workforce, funding arrangements and acceptability to various stakeholders.
Conclusions:
Cognitive behavioural therapy provided by a public psychologist is the most
effective and cost-effective option for the first-line treatment of MDD in children and adolescents. However, this option is not currently accessible by all patients and will require change in policy to allow more widespread uptake. It will also require ‘start-up’ costs and attention to ensuring an adequate workforce.