Dynamics of retinotopic spatial attention revealed by multifocal MEG

Visual focal attention is both fast and spatially localized, making it challenging to investigate using human neu-roimaging paradigms. Here, we used a new multivariate multifocal mapping method with magnetoencephalog-raphy (MEG) to study how focal attention in visual space changes stimulus-evoked responses across the visual field. The observer's task was to detect a color change in the target location, or at the central fixation. Simulta-neously, 24 regions in visual space were stimulated in parallel using an orthogonal, multifocal mapping stimulus sequence. First, we used univariate analysis to estimate stimulus-evoked responses in each channel. Then we applied multivariate pattern analysis to look for attentional effects on the responses. We found that attention to a target location causes two spatially and temporally separate effects. Initially, attentional modulation is brief, observed at around 60-130 ms post stimulus, and modulates responses not only at the target location but also in adjacent regions. A later modulation was observed from around 200 ms, which was specific to the location of the attentional target. The results support the idea that focal attention employs several processing stages and suggest that early attentional modulation is less spatially specific than late.Peer reviewe

Imaging studies on the functional organization and plasticity of human visual cortex

The visual system occupies approximately 25% of the human cerebral cortex. Large part of the visual cortex is organized into retinotopic maps, in which nearby cortical locations represent neighboring points in the visual field. Based on these retinotopic maps and on functional specialization for particular visual stimuli, such as movement or objects, human visual cortex is divided to more than 20 distinct visual areas. This Thesis contributes to our understanding on the functional organization and reorganization of the human visual cortex. In the first study, a method for retinotopic mapping based on multifocal functional magnetic resonance imaging (fMRI) responses was developed. Multifocal refers here to parallel stimulation of multiple regions in the visual field using temporally orthogonal stimulus sequences. Multifocal fMRI provides a straightforward analysis and interpretation of the retinotopic responses. The retinotopy in the primary visual cortex (V1), and in a subset of visual areas beyond V1, can be mapped with the multifocal fMRI. In a separate study, the nonlinear spatial summation of the multifocal responses in V1 was characterized. The interactions between adjacent visual field regions suppressed the multifocal responses, most likely due to the far-reaching spatial summation of V1 cells. The third study showed that training can reorganize visual cortices in an adult patient. The subject was a patient with a chronic visual field defect (homonymous hemianopia) due to a lesion in the visual cortex. We followed the intensive training of visual functions in his blind hemifield with recordings of evoked neuromagnetic responses. After successful training, fMRI measurements revealed an abnormal representation for the trained (right) visual field in the visual areas in the healthy (right) hemisphere, indicating large-scale reorganization of the visual processing. The fMRI tuning curves for spatial frequency were measured in the fourth study. The spatial frequency evoking the strongest fMRI response decreased with the eccentricity of the visual field. The differences in spatial frequency representation between visual areas support the view that these areas may process visual information at different spatial scales. Finally, the cortical sensitivity to phase relations between different spatial frequencies and the significance of congruent phase structure was revealed in multiple human visual areas. The results suggest that higher-level visual areas use the phase congruency information in the detection of natural broadband edges

När det oväntade skett- en metod att stödja andlighet hos anhöriga vid oväntade dödsfall

Syfte med detta examensarbete är att utveckla en resursförstärkande arbetsmetod som kan användas mångprofessionellt inom social- och hälsovården för att stödja andliga behov hos vuxna anhöriga vid plötsliga oväntade dödsfall. Frågeställningarna för arbetet lyder: Vilka andliga behov har vuxna anhöriga vid oväntade dödsfall? Hur kan professionella inom social- och hälsovården stödja vuxna anhörigas andliga behov vid kris eller sorg förorsakade av oväntade dödsfall? Examensarbetet skrivs inom ramen för projektet ”Andlighet, spiritualitet och livsfrågor” vid Yrkeshögskolan Novia i Åbo. Metoden baserar sig på en kvalitativ litteraturöversikt med innehållsanalys som analysmetod. Resultatet av innehållsanalysen visar att professionella med hjälp av kommunikation kan stödja andliga behov som kan uppstå hos anhöriga vid oväntade dödsfall. Kommunikationen består både av samtal och bemötande. Samtal bör möjliggöras genom att professionella skapar rum och tillfällen där anhöriga får hjälp att integrera det oväntade dödsfallet i sin livsberättelse. För att ta till tals svåra tankar och känslor krävs det mod av professionella. I bemötandet är adekvat information, äkta närvaro, lyhördhet och ett empatiskt förhållningssätt viktiga. Resultatet utmynnar i en resursförstärkande metod som kan användas av professionella inom social- och hälsovården för att stödja andliga behov hos anhöriga vid oväntade dödsfall. Metoden tar fasta på den anhörigas egna behov och resurser samt förebygger ohälsa genom tidigt ingripande och stödjande uppföljning.Opinnäytetyön tavoitteena on kehittää voimavaroja vahvistava työmenetelmä, jolla tarjotaan hengellistä tukea omaiselle, joka on kohdannut odottamattoman kuoleman lähipiirissään. Työmenetelmä soveltuu käytettäväksi moniammatillisesti sosiaali- ja terveydenhuollossa. Työn kysymyksenasetteluna on: Mitkä ovat aikuisten omaisten hengelliset tarpeet yllättävässä kuolemassa? Miten sosiaali- ja terveydenhuollon ammattilainen voi tukea aikuisten omaisten hengellisiä tarpeita odottamattoman kuoleman aiheuttamassa kriisi- tai surutyössä? Opinnäytetyö on osa Turun Yrkeshösgskolan Novian hanketta ”Andlighet, spiritualitet och livsfrågor”. Tutkimusmenetelmä perustuu kvalitatiiviseen kirjallisuuskatsaukseen, jossa analyysimenetelmänä on sisällönanalyysi. Sisällönanalyysin tulokset osoittavat, että ammattilainen voi tukea äkillisessä kuolemantapauksessa esille tulevia omaisten hengellisiä tarpeita kommunikaation avulla. Kommunikaatio koostuu sekä keskustelusta että kohtaamisesta. Keskustelu pitäisi toteutua niin, että ammattilainen luo tilaa ja aikaa sille, että omaista autetaan sisällyttämään odottamaton kuolema hänen elämäntarinaansa. Vaikeiden ajatusten ja tunteiden esiin nostaminen vaatii ammattilaiselta rohkeutta. Täsmällinen tieto, aito läsnäolo, kuuntelu ja empaattinen lähestymistapa ovat tärkeitä kohtaamisessa omaisten kanssa. Tuloksena on voimavaroja vahvistava menetelmä, jota sosiaali- ja terveydenhuollon ammattilaiset voivat käyttää työssään tukeakseen omaisen hengellistä tarvetta kohdatessaan läheisen odottamattoman kuoleman kohdatessa. Menetelmä perustuu omaisen omiin tarpeisiin ja voimavaroihin ja sillä ennaltaehkäistään huonoa terveyttä aikaisen puuttumisen ja tukea tarjoavan seurannan avulla.The purpose of this Bachelor´s thesis is to develop a resource promoting work method that can be of use for multi-professionals in social- and healthcare services. This thesis is part of a larger project about spirituality and existential questions, entitled ”Andlighet, spiritualitet och livsfrågor” within the Novia University and Applied Sciences in Turku. In this thesis there are two formulated questions that leads the work: Which spiritual needs do relatives have at unexpected death? How can professionals in the social- and healthcare sector support relatives spiritual needs in a crisis or grief caused by unexpected deaths? The research method is a qualitative literature review with content analysis. In the theoretical part it is described different methods that are already in use as a support to relatives who lost a close person in an unexpected death. The results of this thesis are that professional help of communication can support the spiritual needs that may appear in families where there have been unexpected deaths. The communication consists of both dialogue and encounter with professionals in the social- and healthcare service. The dialogue should be made possible by the professionals by creating room and time where the families are guided to make the unexpected death in to their life story. To take their say of difficult thoughts and feelings, the professional needs courage. For the encounter with relatives adequate information, an authentic presence, responsiveness and an empathetic approach is important. The result concludes a resource promoting method that is to be used in order to support the spiritual needs of relatives who have experienced sudden and unexpected deaths. The method relies on the family´s own needs and resources and prevent disease through supportive follow-up

Optimization of Proprioceptive Stimulation Frequency and Movement Range for fMRI

For vision, audition and tactile sense, the optimal stimulus frequency for fMRI is somewhat known. For proprioception, i.e., the “movement sense”, however, the optimal frequency is unknown. We studied the effect of passive-finger-movement frequency on proprioceptive fMRI responses using a novel pneumatic-movement actuator. Eleven healthy right-handed volunteers participated in the study. The movement actuator passively moved the participant’s right index finger at frequencies of 0.3, 1, 3, 6, 9, or 12 Hz in a blocked design. A functional localizer was used to define regions-of-interest in SI and SII cortices. In addition, effect of movement range on the fMRI responses was tested in a separate session with 1, 3, 5, and 7 mm movement ranges at a fixed 2 Hz frequency. In primary somatosensory (SI) cortex, the responses were stronger at 3 Hz than at 0.3 Hz (p < 0.001) or 1 Hz (p < 0.05), and at ≥6 Hz than 0.3 Hz (p < 0.001 for frequencies ≥ 6 Hz). In secondary somatosensory (SII) cortex, all movements, except at 0.3 Hz, elicited significant responses of similar strength. In addition, 6, 9, and 12-Hz movements elicited a significant offset response in both SI and SII cortices (p < 0.001–0.05). SI cortex required a total stimulation duration of 4 min to elicit significant activations at the group-level whereas for SII cortex 1 min 20 s was sufficient. Increase in the movement range led to stronger responses in SI cortex, but not in SII cortex. Movements above 3 Hz elicited the strongest SI cortex responses, and increase in the movement range enhanced the response strength. We thus recommend that movements at 3–6 Hz with a movement range of 5 mm or higher to be used in future studies of proprioception. Our results are in-line with previous fMRI and PET studies using tactile or median nerve stimulation at different stimulation frequencies

Psychotic-like experiences of young adults in the general population predict mental disorders

Psychotic-like experiences (PLEs) have been identified as risk markers for psychotic disorders and may indicate an individual's susceptibility to mental disorders in general. We examined whether 23 PLEs (assessed with MCIDI questionnaire) reported in young adulthood (n = 1313) predict subsequent psychotic or any mental disorders in the general population. We also investigated whether these possible associations are explained by general psychological distress assessed with the General Health Questionnaire-12 (GHQ-12). The register follow-up period spanned 10-12 years. In Cox regression models, PLEs predicted subsequent psychotic disorders (n = 12) when the effects of age, sex, education, and marital status were adjusted for, but not when general psychological distress was added to the model. Having any mental disorders during follow-up (n = 91) was predicted by PLEs reported at a younger age, when controlling for age, sex, education, marital status, and general psychological distress. In line with earlier results in other age groups, PLEs can be seen as a sign of vulnerability to not just psychotic but all mental disorders during the following years also among young adults in the general population. PLEs were a predictive marker of general psychopathology independently from general psychological distress.Peer reviewe

Radial Frequency Analysis of Contour Shapes in the Visual Cortex

Cumulative psychophysical evidence suggests that the shape of closed contours is analysed by means of their radial frequency components (RFC). However, neurophysiological evidence for RFC-based representations is still missing. We investigated the representation of radial frequency in the human visual cortex with functional magnetic resonance imaging. We parametrically varied the radial frequency, amplitude and local curvature of contour shapes. The stimuli evoked clear responses across visual areas in the univariate analysis, but the response magnitude did not depend on radial frequency or local curvature. Searchlight-based, multivariate representational similarity analysis revealed RFC specific response patterns in areas V2d, V3d, V3AB, and IPS0. Interestingly, RFC-specific representations were not found in hV4 or LO, traditionally associated with visual shape analysis. The modulation amplitude of the shapes did not affect the responses in any visual area. Local curvature, SF-spectrum and contrast energy related representations were found across visual areas but without similar specificity for visual area that was found for RFC. The results suggest that the radial frequency of a closed contour is one of the cortical shape analysis dimensions, represented in the early and mid-level visual areas.Peer reviewe

Perception and Processing of Faces in the Human Brain Is Tuned to Typical Feature Locations.

UNLABELLED: Faces are salient social stimuli whose features attract a stereotypical pattern of fixations. The implications of this gaze behavior for perception and brain activity are largely unknown. Here, we characterize and quantify a retinotopic bias implied by typical gaze behavior toward faces, which leads to eyes and mouth appearing most often in the upper and lower visual field, respectively. We found that the adult human visual system is tuned to these contingencies. In two recognition experiments, recognition performance for isolated face parts was better when they were presented at typical, rather than reversed, visual field locations. The recognition cost of reversed locations was equal to ∼60% of that for whole face inversion in the same sample. Similarly, an fMRI experiment showed that patterns of activity evoked by eye and mouth stimuli in the right inferior occipital gyrus could be separated with significantly higher accuracy when these features were presented at typical, rather than reversed, visual field locations. Our findings demonstrate that human face perception is determined not only by the local position of features within a face context, but by whether features appear at the typical retinotopic location given normal gaze behavior. Such location sensitivity may reflect fine-tuning of category-specific visual processing to retinal input statistics. Our findings further suggest that retinotopic heterogeneity might play a role for face inversion effects and for the understanding of conditions affecting gaze behavior toward faces, such as autism spectrum disorders and congenital prosopagnosia. SIGNIFICANCE STATEMENT: Faces attract our attention and trigger stereotypical patterns of visual fixations, concentrating on inner features, like eyes and mouth. Here we show that the visual system represents face features better when they are shown at retinal positions where they typically fall during natural vision. When facial features were shown at typical (rather than reversed) visual field locations, they were discriminated better by humans and could be decoded with higher accuracy from brain activity patterns in the right occipital face area. This suggests that brain representations of face features do not cover the visual field uniformly. It may help us understand the well-known face-inversion effect and conditions affecting gaze behavior toward faces, such as prosopagnosia and autism spectrum disorders

High risk of in-breast tumor recurrence after BRCA1/2-associated breast cancer

The purpose of the study was to compare breast-conserving therapy (BCT) and mastectomy (M) in BRCA1/2 mutation carriers. Women with invasive breast cancer and a pathogenic mutation in BRCA1 or BRCA2 were included in the study (n = 162). Patients treated with BCT (n = 45) were compared with patients treated with M (n = 118). Endpoints were local recurrence as first recurrence (LR), overall survival (OS), breast cancer death, and distant recurrence. Cumulative incidence was calculated in the presence of competing risks. For calculation of hazard ratios and for multivariable analysis, cause-specific Cox proportional hazards regression was used. Compared to M, BCT was associated with an increased risk of LR in univariable analysis (HR 4.0; 95 % CI 1.6-9.8) and in multivariable analysis adjusting for tumor stage, age, and use of adjuvant chemotherapy (HR 2.9; CI 1.1-7.8). Following M, all local recurrences were seen in the first 5 years after breast cancer diagnosis. Following BCT, the rate of LR continued to be high also after the first 5 years. The cumulative incidence of LR in the BCT group was 15, 25, and 32 % after 5, 10, and 15 years, respectively. There were no significant differences between BCT and M for OS, breast cancer death, or distant recurrence. BRCA1/2 mutation carriers treated with BCT have a high risk of LR, many of which are new primary breast cancers. This must be thoroughly discussed with the patient and is an example of how rapid treatment-focused genetic testing could influence choice of treatment

High risk of in-breast tumor recurrence after BRCA1/2-associated breast cancer.

To access publisher's full text version of this article click on the hyperlink at the bottom of the pageThe purpose of the study was to compare breast-conserving therapy (BCT) and mastectomy (M) in BRCA1/2 mutation carriers. Women with invasive breast cancer and a pathogenic mutation in BRCA1 or BRCA2 were included in the study (n = 162). Patients treated with BCT (n = 45) were compared with patients treated with M (n = 118). Endpoints were local recurrence as first recurrence (LR), overall survival (OS), breast cancer death, and distant recurrence. Cumulative incidence was calculated in the presence of competing risks. For calculation of hazard ratios and for multivariable analysis, cause-specific Cox proportional hazards regression was used. Compared to M, BCT was associated with an increased risk of LR in univariable analysis (HR 4.0; 95 % CI 1.6-9.8) and in multivariable analysis adjusting for tumor stage, age, and use of adjuvant chemotherapy (HR 2.9; CI 1.1-7.8). Following M, all local recurrences were seen in the first 5 years after breast cancer diagnosis. Following BCT, the rate of LR continued to be high also after the first 5 years. The cumulative incidence of LR in the BCT group was 15, 25, and 32 % after 5, 10, and 15 years, respectively. There were no significant differences between BCT and M for OS, breast cancer death, or distant recurrence. BRCA1/2 mutation carriers treated with BCT have a high risk of LR, many of which are new primary breast cancers. This must be thoroughly discussed with the patient and is an example of how rapid treatment-focused genetic testing could influence choice of treatment.Regional Ethical Review Board in Lund Skane County Counsil's Research and Development Foundation Swedish Breast Cancer Association (BRO) Swedish Cancer Society BioCAR

Eye movement behavior in a real-world virtual reality task reveals ADHD in children

Peer reviewe