We proudly present and congratulate Anna-Karin Welmer, Grégoria Kalpouzos and Janina Seubert for approved grants from the Swedish Research Council. See below descriptions of the projects:
Anna-Karin Welmer – Thinking, moving, and falling: Early detection of fall-prone phenotypes as targets for primary interventions—a translational study. Current guidelines for assessment of fall risk in older persons only include screening for severe cognitive impairment. However, even small deficits in specific cognitive domains may interfere with an older person’s ability to compensate for somatic disorders.
In this project, we aim to verify if older persons with combined impairment in physical and cognitive functions represent a specific group with high risk of fracture, dementia, disability and institutionalization. We will also investigate which tests for cognitive and physical functions that can best define this group. Furthermore, we plan to construct and validate a multifactorial index for assessment of fall risk that enables early detection of persons at high risk that can be targets for primary interventions. Finally, we will test and implement the index in clinical settings.
The index will help clinicians identify older persons at increased risk for fall-related injuries at an early stage, when primary interventions are likely to be beneficial. Furthermore, the risk factors identified by using the index may be optimal targets for individualized treatment to avoid or postpone adverse outcomes.
Grégoria Kalpouzos – Impact of age-related brain iron accumulation on neural activity, motor and cognitive performance. Advances in Magnetic Resonance Imaging (MRI) have made it possible to noninvasively and in vivo quantify iron that accumulates in the brain. Intra-cellular nonheme iron, stored in ferritin protein, is a fundamental element that contributes to cellular metabolism. However, an increase in free nonheme iron accumulation is highly toxic, inducing oxidative stress, cellular degradation, and cell death. Excessive concentration of brain iron has been found in disorders such as Parkinson’s disease and Alzheimer’s disease and also in non-pathological aging. At ARC, in a pilot study, we recently demonstrated an adverse effect of higher iron concentration on neural activity and memory performance.
The IRON project will include, at baseline, 250 individuals aged 20–80 years who will undergo MRI with a 3T scanner, offline psychomotor and cognitive testing. Relationships between iron concentration and other neural information will be assessed, e.g., neural activity, neurotransmitters and other metabolites (with MR-Spectroscopy), atrophy, microstructural white matter integrity, together with motor and cognitive outcomes. Moreover, blood sampling will allow us to measure iron components in the blood and perform genetic studies after DNA extraction (for example by investigating the effects of variations in iron genes on several neural and cognitive outcomes).
The quantification of brain iron adds specificity to pathological mechanisms associated with brain aging and may explain motor and cognitive decline. Changes in local iron concentration in the brain may constitute a biological marker for age-related cognitive decline and, possibly, development of neurodegenerative diseases. Means to counteract brain iron overload will be further investigated.
Janina Seubert – Perceptual learning of olfactory-gustatory binding uring food consumption. Unfamiliar foods often elicit feelings of disgust and rejection when eaten for the first time. Familiar foods, on the other hand, can be so pleasant that people want to continue to eat them even when they are full or when they know the product is bad for their health. This pleasant sensory quality evoked by a familiar food, its “flavor”, is the result of a fusion between the taste on the tongue, and the odor that reaches the nose through the throat as the food is consumed. While learned responses to flavors play an important role for food choices and the regulation of appetite, it is not yet known how this fusion of smell and taste is created from simultaneous stimulation with a familiar odor-taste combination in the brain. Similarly, it has also not yet been investigated how brain activation changes when new flavors are learned.
The goal of this research project is to describe the brain mechanisms underlying the evaluation of semantic overlap between odors and tastes, and their role in the emergence of a combined perception of flavor. By means of functional MRI, we will identify brain areas modulated by changes in semantic overlap between odor and taste, and assess their contribution to the formation of a combined flavor sensation. We will also assess the cortical which occur while someone learns a new flavor combination. Participants will chew a chewing gum flavored with an unfamiliar odor-taste combination over the course of a month; behavioral and neuroimaging data will be acquired before, during, and after the flavor has been learned. We will study how a congruency response is formed and delineate the supporting cortical structures, as well as cortical changes to the odor itself that may underlie learning-dependent changes in its reward value.
Taken together, the knowledge gained from this project will help to better understand how gradual encoding of the familiarity of an odor-taste combination contributes to the formation of a flavor response, and how it helps in the evaluation of the relevance of subtle fluctuations in odor-taste congruency that occur during food consumption in everyday life. Describing the plasticity of these responses to flavor learning will be a unique window into the processes which drive the development of adaptive and maladaptive food preferences across the lifespan.