Acute and repeated low dose lipopolysaccharide differentially influences opposite-sex odour preference in male and female mice.
(2025) Physiology & Behaviour
Cantini, D., Choleris, E., Kavaliers, M.
Infection threat affects social preferences and mate choice across species. Female mice have been shown to avoid the odours of sick males acutely treated with relatively high doses of lipopolysaccharide (LPS), the cell wall of Gram-negative bacteria. However, less is known about the responses of both sexes to more naturalistic low level infection threat. Here we considered the responses of both male and female mice to the odours of opposite sex individuals acutely and repeatedly treated with very low and low doses of LPS (1.0 and 25 μg/kg, respectively). There was minimal avoidance of the odours of individuals acutely treated with 1.0 μg/kg LPS, whereas repeated treatment (days 1, 4 and 7), which elicited sensitization (priming), resulted in significant Day 7 avoidance. Conversely, the odours of individuals acutely treated with 25 μg/kg of LPS elicited significant avoidance, whereas repeated treatment, which lead to the development of tolerance, attenuated avoidance. In all cases females displayed a greater avoidance than males of opposite sex odours. Our results show that both male and female mice are sensitive to the nature of the infection status and threat conveyed by the olfactory cues associated with low levels of infection.
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Evaluating the Validity of Gazepoint GP3 HD in Assessing Listening Effort: A pupillometry study.
(2025) American Journal of Audiology.
Rahme, M., Parsa, V., Farahani, M., Folkeard, P., Scollie, S., Johnsrude, I.S.
Purpose: Individuals with hearing loss typically experience greater listening effort, which is the additional recruitment of cognitive/mental resources such as attention and memory to understand speech and can be aversive and tiring. Reducing effort is an important goal of the hearing health care industry. Pupillometry is an objective and increasingly popular measure of listening effort, but gold standard measures of pupil size are expensive and unwieldy. The purpose of this study was to compare a low-cost and portable pupillometry device (Gazepoint GP3 HD) to a more traditional gold standard pupillometry tool (EyeLink 1000) for indexing listening effort via pupil size.
Method: Twenty normal-hearing young adults (age range: 18-23 years) were recruited in this study. Participants' pupil size was measured using the Gazepoint and EyeLink pupillometry devices while listening to Hearing in Noise Test sentences in stationary speech-shaped noise at signal-to-noise ratios (SNRs) ranging from -8 to +8 dB.
Results: Participants' word report accuracy increased from approximately 12% to 100% when the SNRs increased from -8 to +8 dB. Peak pupil diameter decreased for both devices and was smaller with the Gazepoint device. Data quality was comparable for the two devices.
Conclusion: Gazepoint appeared to be an effective pupillometry device that records pupil dilation across a wide range of SNRs, without interfering with the auditory task
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Limited Usable Hearing Unilaterally (LUHU) in Infants and Young Children: A scoping review of tehcnology considerations and developmental outcomes.
(2025) International Journal of Audiology.
Brown, C.L., Bagatto, M.
Objectives: The objective of this scoping review was to examine the developmental impact of limited usable hearing unilaterally (LUHU) and surgical and non-surgical technology outcomes specific to infants and young children who have LUHU.
Design: The Joanna Briggs Institute (JBI) Model of Evidence-Based Healthcare provided a framework. Covidence software was used to manage the articles. Literature searches were conducted in November 2022 and May 2023. Three research audiologists screened the articles followed by full text review by the authors.
Results: The searches resulted in 2953 articles. After removal of duplicates, 888 abstracts were screened. 429 articles underwent full text review. Various selection criteria were applied leaving 66 articles for extraction.
Conclusions: The developmental impact of LUHU is comparable to unilateral hearing loss in general. Hearing-related quality of life and listening fatigue are also impacted. Management counselling to review the various technology options should be guided by Magnetic Resonance Imaging (MRI) results. Bilateral listening benefits may be achieved through cochlear implantation. A remote microphone (RM) system, coupled to the normal hearing ear can improve performance in settings where noise and localisation are problematic. A bone conduction device (BCD) or contralateral routeing of signal (CROS) system may mitigate head shadow effects.
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Social Adversity is Causally Linked to Multimorbidity Including Oral Conditions.
(2025) Journal of Dental Research.
Esemezie, A.O., Lizotte, D.J., Tsakos, G., Gomaa, N.
The fundamental cause theory posits social factors as causes of disease as they encompass access to important resources such as knowledge, wealth, and social networks. While these social factors have been consistently associated with oral and systemic diseases, causality remains unestablished. Here, we estimated the causal effect of social adversity, comprising low economic and social capital, on the development of (1) oral conditions (OC) and (2) multimorbidity including oral conditions (MIOC) in a cohort of middle-aged and older adults over a 7-y period and assessed whether effects varied by age or gender. We analyzed 2 waves from the Canadian Longitudinal Study on Aging (CLSA) (2011 and 2018). Social adversity comprised low economic (income) and social capital (community participation, social relationships). OC was defined as having 1 or more of poor self-reported oral health, lack of functional dentition (<20 natural teeth), or edentulism. Participants with an OC at baseline were excluded. MIOC was defined as having 2 or more chronic diseases and an OC. Logistic marginal structural models with inverse probability weighting estimated the causal odds ratio (OR) of developing both outcomes, controlling for sociodemographic and behavioral factors. In a total of 23,366 participants, 14% experienced social adversity at baseline, with a prevalence of 17% OC and 7% MIOC at follow-up. Social adversity significantly increased the odds of developing OC (OR = 1.9, 95% confidence interval [CI] 1.7, 2.2) and MIOC (OR = 1.7, 95% CI 1.5, 2.0) at follow-up. The observed effects were strongest in the middle-aged group, with similar odds observed in both men and women. Our findings indicate that social and economic capital are causally linked to the development of OC and MIOC over time. We suggest that policies for healthy aging should prioritize action on social and living conditions.
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Experience-driven Predictability Does Not Influence Neural Entrainment to the Beat.
(2025) Journal of Cognitive Neuroscience.
Hoddinott, J.D., Henry, M.J., Grahn, J.A.
Humans spontaneously synchronize movements to a perceived underlying pulse, or beat, in music. Beat perception may be indexed by the synchronization of neural oscillations to the beat, marked by increases in EEG amplitude at the beat frequency [Nozaradan, S., Peretz, I., Missal, M., & Mouraux, A. Tagging the neuronal entrainment to beat and meter. Journal of Neuroscience, 31, 10234-10240, 2011]. Indeed, neural synchronization to the beat appears stronger for strong-beat than non-beat rhythms [Tal, I., Large, E. W., Rabinovitch, E., Wei, Y., Schroeder, C. E., Poeppel, D., et al. Neural entrainment to the beat: The "missing-pulse" phenomenon. The Journal of Neuroscience, 37, 6331-6341, 2017] and may underlie the generation of an internal representation of beat. However, because we are exposed disproportionately to strong-beat rhythms (e.g., most Western music) in the environment, comparisons of neural responses to strong-beat and non-beat rhythms may be confounded by relative differences in familiarity. Here, we dissociated beat-related and familiarity-related neural responses by comparing EEG amplitudes during the perception of strong-beat and non-beat rhythms that were either novel or made familiar through training. First, we recorded EEG from participants while they listened to a set of strong-beat, weak-beat, and non-beat rhythms. Then, they were trained on half of the rhythms over four behavioral sessions by listening to and tapping along with them, such that half of the rhythms were familiar by the end of training. Finally, EEG responses to the full rhythm set (half now familiar, half still unfamiliar) were recorded posttraining. Results show no effect of training on EEG amplitude at beat or stimulus-related frequencies and little evidence of familiarity-driven changes in EEG amplitude for weak- and non-beat rhythms. This suggests that oscillatory entrainment to the beat is not driven by familiarity and therefore likely reflects beat processing..
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Integrating Optical Neuroscience Tools into Touchscreen Operant Systems.
(2025) Nature Protocols.
Piantadosi, P.T., Princz-Lebel, O., Skirzewski, M., Dumont, J.F., Palmer, D., Memar, S., Saksida, L.M., Prado, V.F., Prado, M.A.M., Bussey, T.J., Holmes, A.
Unlocking the neural regulation of complex behavior is a foundational goal of brain science. Touchscreen-based assessments of behavior have been used extensively in the pursuit of this goal, with traditional pharmacological and neurochemical approaches being employed to provide key insights into underlying neural systems. So far, optically based approaches to measure and manipulate neural function, which have begun to revolutionize our understanding of relatively simple behaviors, have been less widely adopted for more complex cognitive functions of the type assessed with touchscreen-based behavioral tasks. Here we provide guidance and procedural descriptions to enable researchers to integrate optically based manipulation and measurement techniques into their touchscreen experimental systems. We focus primarily on three techniques, optogenetic manipulation, fiber photometry and microendoscopic imaging, describing experimental design adjustments that we have found to be critical to the successful integration of these approaches with extant touchscreen behavior pipelines. These include factors related to surgical procedures and timing, alterations to touchscreen operant environments and approaches to synchronizing light delivery and task design. A detailed protocol is included for each of the three techniques, covering their use from implementation through data analysis. The procedures in this protocol can be conducted in as short a time as a few days or over the course of weeks or months.
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