Journal Articles

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    Do you remember? Consumer reactions to health-related information on snacks in repeated exposure
    (Elsevier Ltd, 2025-05) Stickel L; Poggesi S; Grunert KG; Lähteenmäki L; Hort J
    Health-related information on pre-packed food products can enhance purchase intention and healthy choices. However, retained positive influence of health-related information on product liking is necessary to help consumers make informed decisions about a healthy diet in the long term. According to information-reduction theory, consumers reduce the amount of information that is processed in repeated exposure. Hence, increasing familiarity with a product could lead to increased levels of ignoring health-related information and an increasing reliance on product experience-based associations. These effects were tested in a laboratory study, involving actual food tasting and repeated exposure across two sessions. Participants (N = 154) were invited to evaluate yoghurts with and without health-related information with a screen representation of the product packaging. Differences in product evaluations and attention paid to health-related information between the two sessions were recorded using both implicit and explicit methods. Findings reveal that, despite a decrease in visual attention to health-related information, the perceived healthiness of the products remained stable. However, consumers reported lower perceived tastiness when health-related information was present. The findings underscore the importance of compelling taste experiences, as taste beliefs, in contrast to health beliefs, consistently influenced product liking. Finally, the findings emphasised the need for a comprehensive understanding of consumer reactions to healthier food products that considers both implicit and explicit responses.
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    Evaluation of insensibility in humane slaughter of teleost fish including the use of electroencephalogram with a case study on farmed barramundi (Lates calcarifer)
    (Elsevier B V, 2024-09-15) Wahltinez SJ; Cohen S; Hardy-Smith P; Huynh C; Kells N
    Humane slaughter methods for fish are an important facet of responsible farming practice that can both minimise animal distress and improve product quality. In addition, consumers are increasingly demanding good welfare across all phases of farmed animal production, including at slaughter. As a result, many intergovernmental organisations, government bodies, and third-party certification schemes now include fish slaughter practices in their legislation, guidelines, and audit schemes. In order to be considered humane, slaughter methods should not be aversive to the fish and should result in rapid insensibility without recovery of consciousness prior to death. Where the act of slaughter does not cause immediate loss of sensibility, this should be preceded by an effective stunning method that induces rapid insensibility that is maintained until death. However, determining when fish are insensible is challenging. The effective evaluation of insensibility and stunning is important to prevent any suffering or distress that might occur when invasive killing methods, such as bleeding or evisceration, are used. Insensibility may be assessed using observable indicators such as fish behaviour, or objectively through measuring brain activity using electroencephalography. There is concern that observable indicators, such as opercular movement, righting responses, and spontaneous movement, may not be reliable signs of insensibility. It is therefore important to validate these observable indicators using objective measures, which can determine when electrical changes in the brain occur that indicate insensibility. Barramundi (Lates calcarifer) are an important aquaculture species that are farmed worldwide. Currently, this species is usually slaughtered by ice slurry immersion, a practice which has raised welfare concerns in other fish species. The objectives of this review are to provide background on current slaughter methods used for teleost fish, to summarise the methods used to evaluate insensibility in fish at stunning and slaughter, and to describe the current practices and future directions for the slaughter of farmed barramundi.
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    Alterations in rhythmic and non‐rhythmic resting‐state EEG activity and their link to cognition in older age
    (Elsevier Inc, 2023-03) Cesnaite E; Steinfath P; Jamshidi Idaji M; Stephani T; Kumral D; Haufe S; Sander C; Hensch T; Hegerl U; Riedel-Heller S; Röhr S; Schroeter ML; Witte AV; Villringer A; Nikulin VV
    While many structural and biochemical changes in the brain have previously been associated with older age, findings concerning functional properties of neuronal networks, as reflected in their electrophysiological signatures, remain rather controversial. These discrepancies might arise due to several reasons, including diverse factors determining general spectral slowing in the alpha frequency range as well as amplitude mixing between the rhythmic and non-rhythmic parameters. We used a large dataset (N = 1703, mean age 70) to comprehensively investigate age-related alterations in multiple EEG biomarkers taking into account rhythmic and non-rhythmic activity and their individual contributions to cognitive performance. While we found strong evidence for an individual alpha peak frequency (IAF) decline in older age, we did not observe a significant relationship between theta power and age while controlling for IAF. Not only did IAF decline with age, but it was also positively associated with interference resolution in a working memory task primarily in the right and left temporal lobes suggesting its functional role in information sampling. Critically, we did not detect a significant relationship between alpha power and age when controlling for the 1/f spectral slope, while the latter one showed age-related alterations. These findings thus suggest that the entanglement of IAF slowing and power in the theta frequency range, as well as 1/f slope and alpha power measures, might explain inconsistencies reported previously in the literature. Finally, despite the absence of age-related alterations, alpha power was negatively associated with the speed of processing in the right frontal lobe while 1/f slope showed no consistent relationship to cognitive performance. Our results thus demonstrate that multiple electrophysiological features, as well as their interplay, should be considered for the comprehensive assessment of association between age, neuronal activity, and cognitive performance.
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    Bedside EEG predicts longitudinal behavioural changes in disorders of consciousness
    (Elsevier Inc, 2020) Bareham CA; Roberts N; Allanson J; Hutchinson PJA; Pickard JD; Menon DK; Chennu S
    Providing an accurate prognosis for prolonged disorder of consciousness (pDOC) patients remains a clinical challenge. Large cross-sectional studies have demonstrated the diagnostic and prognostic value of functional brain networks measured using high-density electroencephalography (hdEEG). Nonetheless, the prognostic value of these neural measures has yet to be assessed by longitudinal follow-up. We address this gap by assessing the utility of hdEEG to prognosticate long-term behavioural outcome, employing longitudinal data collected from a cohort of patients assessed systematically with resting hdEEG and the Coma Recovery Scale-Revised (CRS-R) at the bedside over a period of two years. We used canonical correlation analysis to relate clinical (including CRS-R scores combined with demographic variables) and hdEEG variables to each other. This analysis revealed that the patient’s age, and the hdEEG theta band power and alpha band connectivity, contributed most significantly to the relationship between hdEEG and clinical variables. Further, we found that hdEEG measures recorded at the time of assessment augmented clinical measures in predicting CRS-R scores at the next assessment. Moreover, the rate of hdEEG change not only predicted later changes in CRS-R scores, but also outperformed clinical measures in terms of prognostic power. Together, these findings suggest that improvements in functional brain networks precede changes in behavioural awareness in pDOC. We demonstrate here that bedside hdEEG assessments conducted at specialist nursing homes are feasible, have clinical utility, and can complement clinical knowledge and systematic behavioural assessments to inform prognosis and care.
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    Post-natal development of EEG responses to noxious stimulation in pigs (Sus scrofa) aged 1-15 days
    (Ingenta on behalf of the Universities Federation for Animal Welfare (UFAW), 1/08/2019) Kells NJ; Beausoleil NJ; Sutherland MA; Johnson CB
    This study examined electroencephalographic (EEG) indices of acute nociception in pigs (Sus scrofa) aged 1, 5, 7, 10, 12 and 15 days, post-natal. Ten pigs per age were anaesthetised with halothane in oxygen and maintained at a light plane of anaesthesia. EEG was recorded bilaterally using a five-electrode montage. Following a 10-min baseline period, tails were docked using side-cutter pliers and recording continued for a further 5 min. Changes in the median frequency (F50), 95% spectral edge frequency (F95) and total power (PTOT) of the EEG were used to assess nociception. Tail-docking at one day of age induced no significant changes in the EEG spectrum. A typical nociceptive response, characterised by an increase in F50 and decrease in PTOT, was evident at ten days of age, with five and seven day old pigs exhibiting responses in either F50 or PTOT only. Pooling of data into ≤ 7 days of age and > 7 days of age revealed F50 was higher overall in the older group. Whilst PTOT decreased after docking in both groups, this response was larger and more prolonged in the older group. F95 increased after docking in the older pigs only. Overall, these data provide evidence of an increase in cortical responsiveness to noxious stimulation with increasing post-natal age, suggesting there may be qualitative differences in pain perception between age groups. Further, the data provide some support for current recommendations that tail-docking and other painful husbandry procedures be performed within seven days of birth in order to minimise their impact on animal welfare.
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    Effects of halothane on the electroencephalogram of the chicken
    (John Wiley and Sons, Ltd, 15/05/2018) McIlhone AE; Beausoleil NJ; Kells NJ; Johnson CB; Mellor DJ
    Little is known about the effects of inhalant anaesthetics on the avian electroencephalogram (EEG). The effects of halothane on the avian EEG are of interest, as this agent has been widely used to study nociception and analgesia in mammals. The objective of this study was to characterize the effects of halothane anaesthesia on the EEG of the chicken. Twelve female Hyline Brown chickens aged 8-10 weeks were anaesthetized with halothane in oxygen. For each bird, anaesthesia was progressively increased from 1-1.5 to 2 times the Minimum Anesthetic Concentration (MAC), then progressively decreased again. At each concentration, a sample of EEG was recorded after a 10-min stabilization period. The mean Total Power (PTOT ), Median Frequency (F50) and 95% Spectral Edge Frequency (F95) were calculated at each halothane MAC, along with the Burst Suppression Ratio (BSR). Burst suppression was rare and BSR did not differ between halothane concentrations. Increasing halothane concentration from 1 to 2 MAC resulted in a decrease in F50 and increase in PTOT , while F95 increased when MAC was reduced from 1.5 to 1. The results indicate dose-dependent spectral EEG changes consistent with deepening anaesthesia in response to increasing halothane MAC. As burst suppression was rare, even at 1.5 or 2 times MAC, halothane may be a suitable anaesthetic agent for use in future studies exploring EEG activity in anaesthetized birds.