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Recent work has recognized a gradient-like organization in cortical function, spanning from primary sensory to transmodal cortices. It has been suggested that this axis is aligned with regional differences in neurotransmitter expression. Given the abundance of dopamine D1-receptors (D1DR), and its importance for modulation and neural gain, we tested the hypothesis that D1DR organization is aligned with functional architecture, and that inter-regional relationships in D1DR co-expression modulate functional cross talk. Using the world's largest dopamine D1DR-PET and MRI database (N = 180%, 50% female), we demonstrate that D1DR organization follows a unimodal–transmodal hierarchy, expressing a high spatial correspondence to the principal gradient of functional connectivity. We also demonstrate that individual differences in D1DR density between unimodal and transmodal regions are associated with functional differentiation of the apices in the cortical hierarchy. Finally, we show that spatial co-expression of D1DR primarily modulates couplings within, but not between, functional networks. Together, our results show that D1DR co-expression provides a biomolecular layer to the functional organization of the brain.

Age-related alterations in D1-like dopamine receptor (D1DR) have distinct implications for human cognition and behavior during development and aging, but the timing of these periods remains undefined. Enabled by a large sample of in vivo assessments (n = 180, age 20 to 80 years of age, 50% female), we discover that age related D1DR differences pivot at approximately 40 years of age in several brain regions. Focusing on the most age-sensitive dopamine-rich region, we observe opposing preand post-forties interrelations among caudate D1DR, cortico-striatal functional connectivity, and memory. Finally, particularly caudate D1DR differences in midlife and beyond, but not in early adulthood, associate with manifestation of white matter lesions. The present results support a model by which excessive dopamine modulation in early adulthood and insufficient modulation in aging are deleterious to brain function and cognition, thus challenging a prevailing view of monotonic D1DR function across the adult lifespan.

Concomitant exploration of structural, functional, and neurochemical brain mechanisms underlying age-related cognitive decline is crucial in promoting healthy aging. Here, we present the DopamiNe, Age, connectoMe, and Cognition (DyNAMiC) project, a multimodal, prospective 5-year longitudinal study spanning the adult human lifespan. DyNAMiC examines age-related changes in the brain’s structural and functional connectome in relation to changes in dopamine D1 receptor availability (D1DR), and their associations to cognitive decline. Critically, due to the complete lack of longitudinal D1DR data, the true trajectory of one of the most age-sensitive dopamine systems remains unknown. The first DyNAMiC wave included 180 healthy participants (20–80 years). Brain imaging included magnetic resonance imaging assessing brain structure (white matter, gray matter, iron), perfusion, and function (during rest and task), and positron emission tomography (PET) with the [11C]SCH23390 radioligand. A subsample (n = 20, >65 years) was additionally scanned with [11C]raclopride PET measuring D2DR. Age-related variation was evident for multiple modalities, such as D1DR; D2DR, and performance across the domains of episodic memory, working memory, and perceptual speed. Initial analyses demonstrated an inverted u-shaped association between D1DR and resting-state functional connectivity across cortical network nodes, such that regions with intermediate D1DR levels showed the highest levels of nodal strength. Evident within each age group, this is the first observation of such an association across the adult lifespan, suggesting that emergent functional architecture depends on underlying D1DR systems. Taken together, DyNAMiC is the largest D1DR study worldwide, and will enable a comprehensive examination of brain mechanisms underlying age-related cognitive decline.

Bakgrund: Procedurrelaterad smärta och oro kan innebära ett lidande för barn inom sjukvården vilket kan medföra att barn bygger upp en sjukvårdsrädsla. Ett sätt att lindra det kan vara genom avledning, information samt låta barnet vara delaktigt i sin vård. När det inte är tillräckligt kan lustgas användas eftersom det ger både smärtlindrande och lugnande effekt. Syfte: Att undersöka sjuksköterskors erfarenheter av att använda lustgas till barn vid procedurrelaterad smärta ochoro. Metod: Studien genomfördes utifrån kvalitativ design. Tio sjuksköterskor intervjuades genom en semistrukturerad intervjuguide. Materialet analyserades utifrån en kvalitativ metod. Resultat: Resultatet presenteras i tre kategorier och åtta underkategorier. Kategorierna innefattar: Skapa en optimal situation, Lustgas är en effektiv metod men bör inte vara det enda alternativet och Erfarenhet och utbildning ger trygghet. Barn ska bli informerade och vara delaktiga i sin vård. Lustgas är en effektiv metod men andra avledningsmetoder bör provas först och mindre erfarna sjuksköterskor kan känna osäkerhet. Konklusion: Lustgas är en effektiv metod. Genom att involvera barn i sin vård ökar deras delaktighet. Därtill behöver sjuksköterskor fortlöpande lustgasutbildning för att känna trygghet. Det skulle kunna bidra till en förbättrad lustgasanvändning och en optimal barnsjukvård., Background: Procedure-related pain and anxiety can cause suffering to children in healthcare, which can lead to children building up a fear of healthcare. One way to alleviate this can be by distraction, information and letting the child be involved in their care. When it is not enough nitrous oxide can be used since it provides both a pain relieving and a calming effect. Purpose: To examine nurses’ experiences of using nitrous oxide to children during procedure-related pain and anxiety. Method: The study was conducted through a qualitative design. Ten nurses were interviewed based on a semi-structured interview guide. The material was analyzed based on a qualitative content analysis. Result: The result is presented in three categories and eight sub-categories. The categories include: Create an optimal situation, Nitrous oxide is an effective method but should not be the only option and Experience and education provides security. Children should be informed and involved in their care. Nitrous oxide is an effective method but other distraction methods should be tried first and less experienced nurses may feel insecure. Conclusion: Nitrous oxide is an effective method. By involving children in their care, their participation increases. In addition, nurses need continuous nitrous oxide training to feel safe. It could contribute to improved nitrous oxide use and optimal pediatric care.

The hippocampal longitudinal axis has been linked to dissociated functional networks relevant to episodic memory. However, the organization of axis-dependent networks and their relation to episodic memory in aging remains less explored. Moreover, age-related deterioration of the dopamine (DA) system, affecting memory and functional network properties, might constitute a source of reduced specificity of hippocampal networks in aging. Here, we characterized axis-dependent large-scale hippocampal resting-state networks, their relevance to episodic memory, and links to DA in older individuals (n = 170, 64-68 years). Partial least squares identified 2 dissociated networks differentially connected to the anterior and posterior hippocampus. These overlapped with anterior-temporal/posterior-medial networks in young adults, indicating preserved organization of axis-dependent connectivity in old age. However, axis-specific networks were overall unrelated to memory and hippocampal DA D2 receptor availability (D2DR) measured with [11C]-raclopride positron emission tomography. Further analyses identified a memory-related network modulated by hippocampal D2DR, equally connected to anterior-posterior regions. This network included medial frontal, posterior parietal, and striatal areas. The results add to the current understanding of large-scale hippocampal connectivity in aging, demonstrating axis-dependent connectivity with dissociated anterior and posterior networks, as well as a primary role in episodic memory of connectivity shared by regions along the hippocampalaxis.

The hippocampus (HC) interacts with distributed brain regions to support memory and shows significant volume reductions in aging, but little is known about age effects on hippocampal whole-brain structural covariance. It is also unclear whether the anterior and posterior HC show similar or distinct patterns of whole-brain covariance and to what extent these are related to memory functions organized along the hippocampal longitudinal axis. Using the multivariate approach partial least squares, we assessed structural whole-brain covariance of the HC in addition to regional volume, in young, middle-aged and older adults (n = 221), and assessed associations with episodic and spatial memory. Based on findings of sex differences in both memory and brain aging, we further considered sex as a potential modulating factor of age effects. There were two main covariance patterns: one capturing common anterior and posterior covariance, and one differentiating the two regions by capturing anterior-specific covariance only. These patterns were differentially related to associative memory while unrelated to measures of single-item memory and spatial memory. Although patterns were qualitatively comparable across age groups, participants' expression of both patterns decreased with age, independently of sex. The results suggest that the organization of hippocampal structural whole-brain covariance remains stable across age, but that the integrity of these networks decreases as the brain undergoes age-related alterations.

fMRI studies have identified distinct resting-state functional connectivity (RSFC) networks associated with the anterior and posterior hippocampus. However, the functional relevance of these two networks is still largely unknown. Hippocampal lesion studies and task-related fMRI point to a role for the anterior hippocampus in non-spatial episodic memory and the posterior hippocampus in spatial memory. We used Relevance Vector Regression (RVR), a machine-learning method that enables predictions of continuous outcome measures from multivariate patterns of brain imaging data, to test the hypothesis that patterns of whole-brain RSFC associated with the anterior hippocampus predict episodic memory performance, while patterns of whole-brain RSFC associated with the posterior hippocampus predict spatial memory performance. Magnetic resonance imaging (MRI) and memory assessment took place at two separate occasions. The anterior and posterior RSFC largely corresponded with previous findings, and showed no effect of laterality. Supporting the hypothesis, RVR produced accurate predictions of episodic performance from anterior, but not posterior, RSFC, and accurate predictions of spatial performance from posterior, but not anterior, RSFC. In contrast, a univariate approach could not predict performance from resting-state connectivity. This supports a functional dissociation between the anterior and posterior hippocampus, and indicates a multivariate relationship between intrinsic functional networks and cognitive performance within specific domains, that is relatively stable over time.

Poster presented at the Cognitive Neuroscience Society Annual Meeting, Boston, USA

The pattern separation process, where sensory input is given an individual place in memory without compromising or overwriting older memory representations, is highly sensitive to small changes in input, and as the similarity between items increases so does pattern separation demand (Clelland et al., 2009; Yassa & Stark, 2011). This experiment tested performance on a pattern separation-dependent spatial discrimination task after manipulating participants’ processing styles using the NAVON task. The specific hypothesis was that local processing before testing – a detail oriented approach – would benefit discrimination performance for items at a high level of pattern separation demand, since such items only differ from each other on a detail-level. The constructed material successfully reflected three levels of pattern separation demand, but the processing manipulation only showed different effects on performance at a medium level of demand, where it was best following local processing.

Alzheimers sjukdom är vanlig sjukdom i Sverige och övriga världen där symptombilden har en negativ inverkan på personens livssituation. Syftet med studien var att belysa vilka positiva effekter fysisk aktivitet har hos patienter med Alzheimers sjukdom. Studien genomfördes som en litteraturstudie och var grundad på 15 vetenskapliga artiklar. Resultatet indelades i tre huvudkategorier, påverkan på sinnesstämning, förbättrade kognitiva funktioner och förbättrad fysisk förmåga. Genom att utöva fysisk aktivitet förbättrades sinnesstämningen hos patienterna vilket visade sig genom att de blev mindre rastlösa, agiterade och oroliga. Psykofarmakaförbrukningen reducerades och patienterna kände sig mindre nedstämda efter att ha deltagit i fysiska övningar. Den kognitiva funktionen hos patienterna förbättrades, likaså förmågan att utföra den allmänna dagliga livsföringen. Genom fysisk träning blev patienterna rörligare, flexiblare, starkare, snabbare och de fick bättre balans. Resultatet visade att utövandet av fysisk aktivitet har olika positiva effekter hos patienter med Alzheimers sjukdom. Vidare forskning skulle kunna inrikta sig på vilken betydelse regelbunden träning har för att uppnå en positiv effekt av träningen. Patienter med Alzheimers sjukdom har lika stort behov av fysisk aktivitet som övriga befolkningen, det är därför betydelsefullt att patienternas behov av aktivitet uppmärksammas av sjuksköterskan., Alzheimer´s disease is a common disease in Sweden and in rest of the world. The symptoms have a negative impact on the person's life situation. The purpose of this study was to investigate the positive impact of physical activity in patients with Alzheimer's disease. The study was conducted as a literature review and was based on 15 scientific articles. The results were divided into three main categories, the effect on mood, improved cognitive function and improved physical ability. The patients’ moods were improved by participation in physical activities and they became less restless, agitated and anxious. The consumption of psychotropic drugs was reduced and the patients felt less depressed after taking part in physical exercises. The cognitive function of patients improved, likewise the ability to perform the activities of daily living. The patients who participated in physical exercises became more mobilized, more flexible, stronger, faster, and they improved their balance. The results showed that physical activity has different positive impacts on patients with Alzheimer´s disease. Additional research could focus on what impact adherence has for achieving a positive effect of physical activity. Patients with Alzheimer’s disease have equal needs of physical activity as other people, therefore it´s important that nurses are aware of the patients’ needs for activity.

Examining the relation between olfactory memory and verbal processing, this study aimed at exploring the phenomenon of verbal overshadowing and its effect on novices’ and experts’ memory performance. Two main questions were asked; would olfactory memory be susceptible to overshadowing and would subjects, not only generating their own verbalizations but also being given objectively correct ones, show signs of recognition impairment? The results were predicted to show impaired performance for the novices in the verbalization conditions but not for the experts. The over all performance on the recognition test was too weak for allowing any generalizations, but in line with the hypothesis the weakest performance for novices was observed to be the self-generated verbalization condition. Surprisingly and contrary to the hypothesis, not only experts but also novices seemed to benefit from the objective descriptions.

Functional connectivity across large-scale brain networks alters in older age and changes are often associated with memory decline. Studies assessing hippocampal resting-state functional connectivity (rsFC), however, rarely consider the anterior and posterior hippocampus separately, although evidence suggests they are part of two distinct networks differentially supporting memory. While only a limited number of studies have considered age effects on axis-related hippocampal connectivity, findings suggest that rsFC of the two regions display differential effects of age. Reports on the link between such effects and memory are however inconclusive, and previous findings mainly concern episodic memory, ignoring spatial memory also dependent on the hippocampus. Here, we therefore assessed age effects on axis-related hippocampal rsFC, accounting for associations with both episodic and spatial memory in young, middle-aged and older adults (n=194). The anterior and posterior hippocampus showed different age-related decreases in connectivity assessed across middle and older age, but common to the regions was a decreased coupling with the medial orbitofrontal cortex. Only connectivity between the posterior hippocampus and the lingual gyrus increased as a function of age, displaying negative associations with episodic memory. In contrast, the region’s connectivity with the insula, decreasing with age, was positively related to spatial memory. Consistent with previous reports, our findings indicate that hippocampal rsFC vary with age in an axis-dependent manner, and further add to the knowledge on this differentiation’s relevance to memory by showing that age-related rsFC of the anterior and posterior hippocampus is differentially associated with episodic and spatial memory.