Parkinson’s disease (PD) is known for its motor alterations, but the importance of non-motor symptoms (NMSs), such as olfactory dysfunction (OD), is increasingly recognized. OD may manifest during the prodromal period of the disease, even before motor symptoms appear. Therefore, it is suggested that this symptom could be considered a marker of PD. This article briefly describes PD, the evolution of the knowledge about OD in PD, the prevalence of this NMS and its role in diagnosis and as a marker of PD progression, the assessment of olfaction in patients with PD, the role of α-synuclein and its aggregates in the pathophysiology of PD, and then describes some functional, morphological, and histological alterations observed in different structures related to the olfactory system, such as the olfactory epithelium, olfactory bulb, anterior olfactory nucleus, olfactory tract, piriform cortex, hippocampus, orbitofrontal cortex, and amygdala. In addition, considering the growing evidence that suggests that the cerebellum is also involved in the olfactory system, it has also been included in this work. Comprehending the existing functional and neuroanatomical alterations in PD could be relevant for a better understanding of the mechanisms behind OD in patients with this neurodegenerative disorder.

Noise pollution poses a serious threat to human health and well-being, especially in educational environments where concentration and learning are essential. While urban noise has been widely studied, its effects within university settings remain underexplored. This study investigates environmental noise and student perceptions on two campuses of the University of Guadalajara, Mexico—one located in an urban area and the other in a semi-rural setting. Noise levels were measured using the CESVA-SC260 integrating instrument (CESVA Instruments, SLU, Barcelona, Spain), and student perceptions were gathered through a survey. A total of 731 students participated, with 357 from the urban campus and 374 from the semi-rural one. Results showed that noise levels on both campuses frequently exceeded the WHO’s recommended limit of 55 dB(A) for educational facilities, with readings between 40.9 and 85.0 dB(A); 89% of measurements surpassed the threshold. Major sources of noise included vehicular traffic, student gatherings, and construction-related machinery. Survey responses indicated that 41% of students perceived noise as a health risk, and 96% reported adverse effects on well-being and identified it as a disruptor of academic tasks. These findings underscore the pressing need for targeted noise management strategies in university environments and call for further research into effective, context-specific interventions that enhances learning conditions.