Seeing or Doing? Influence of Visual and Motor Familiarity in Action Observation

The human brain contains specialized circuits for observing and understanding actions. Previous studies have not distinguished whether this "mirror system" uses specialized motor representations or general processes of visual inference and knowledge to understand observed actions. We report the first neuroimaging study to distinguish between these alternatives. Purely motoric influences on perception have been shown behaviorally, but their neural bases are unknown. We used fMRI to reveal the neural bases of motor influences on action observation. We controlled for visual and knowledge effects by studying expert dancers. Some ballet moves are performed by only one gender. However, male and female dancers train together and have equal visual familiarity with all moves. Male and female dancers viewed videos of gender-specific male and female ballet moves. We found greater premotor, parietal, and cerebellar activity when dancers viewed moves from their own motor repertoire, compared to opposite-gender moves that they frequently saw but did not perform. Our results show that mirror circuits have a purely motor response over and above visual representations of action. We understand actions not only by visual recognition, but also motorically. In addition, we confirm that the cerebellum is part of the action observation network.     

When Are Random Data Not Random,or Is the PTP Test Useful?

Recently, empirical evidence was presented that the permutation tail probability (PTP) test has extremely low discriminatory power when assessing character covariance in phylogenetic data based on bootstrap measures of confidence. Here we are concerned with the problem of using one statistical approach, especially when applied to empirical data, to judge the performance of another. Applying an appropriate statistical approach, we statistically demonstrated that the PTP test is extremely weak in detecting the absence of character covariation. In addition, we show that PTP is highly dependent on the number of terminals and the proportion of character states in phylogenetic matrices. In conclusion, we advocate the use of simulation studies when testing the performance of statistical tools applied to phylogenetic data.     

To Coil,or Not to – Activity Associated Ambiguity in Defense Responses of Millipedes

Arthropods, like most other animals, generally exhibit strong defense responses to predatory threats. This communication aims to demonstrate that the intensity of expression of a particular defense response may be affected by the kind of activity an arthropod is currently performing. Millipedes coil when threatened, and we analyzed coiling responses in the millipede Phyllogonostreptus nigrolabiatus during feeding, resting and walking. Further, variation in response was also quantified with respect to the inclination of the body – horizontal on ground and perpendicular on stems of trees. The millipedes (n = 199) were tapped on their bodies with a short stick to elicit the response. Three levels of responses were obtained – complete, partial and nil. On ground, although most millipedes tended to show complete coiling, the responses alternated between the two extremes among the feeding ones; resting and walking millipedes predominantly displayed complete response. On trees however, most millipedes were non-responsive, although walking millipedes tended to show relatively greater proportion of complete response. These results prove that different activities can elicit variation in a defense response, and so does body inclination in millipedes.     

It’s Not Easy Being Blue: Are There Olfactory and Visual Trade-Offs in Plant Signalling?

Understanding the signals used by plants to attract seed disperses is a pervasive quest in evolutionary and sensory biology. Fruit size, colour, and odour variation have long been discussed in the controversial context of dispersal syndromes targeting olfactory-oriented versus visually-oriented foragers. Trade-offs in signal investment could impose important physiological constraints on plants, yet have been largely ignored. Here, we measure the reflectance and volatile organic compounds of a community of Malagasy plants and our results indicate that extant plant signals may represent a trade-off between olfactory and chromatic signals. Blue pigments are the most visually-effective – blue is a colour that is visually salient to all known seed dispersing animals within the study system. Additionally, plants with blue-reflecting fruits are less odiferous than plants that reflect primarily in other regions of the colour spectrum.     

Trisomy 8, a Cytogenetic Abnormality in Myelodysplastic Syndromes,Is Constitutional or Not?

Isolated trisomy 8 is not considered presumptive evidence of myelodysplastic syndrome (MDS) in cases without minimal morphological criteria. One reason given is that trisomy 8 (+8) can be found as a constitutional mosaicism (cT8M). We tried to clarify the incidence of cT8M in myeloid neoplasms, specifically in MDS, and the diagnostic value of isolated +8 in MDS. Twenty-two MDS and 10 other myeloid neoplasms carrying +8 were studied. Trisomy 8 was determined in peripheral blood by conventional cytogenetics (CC) and on granulocytes, CD3+ lymphocytes and oral mucosa cells by fluorescence in situ hybridization (FISH). In peripheral blood CC, +8 was seen in 4/32 patients. By FISH, only one patient with chronic myelomonocytic leukemia showed +8 in all cell samples and was interpreted as a cT8M. In our series +8 was acquired in all MDS. Probably, once discarded cT8M by FISH from CD3+ lymphocytes and non-hematological cells, +8 should be considered with enough evidence to MDS.     

Simple Plans or Sophisticated Habits? State,Transition and Learning Interactions in the Two-Step Task

The recently developed ‘two-step’ behavioural task promises to differentiate model-based from model-free reinforcement learning, while generating neurophysiologically-friendly decision datasets with parametric variation of decision variables. These desirable features have prompted its widespread adoption. Here, we analyse the interactions between a range of different strategies and the structure of transitions and outcomes in order to examine constraints on what can be learned from behavioural performance. The task involves a trade-off between the need for stochasticity, to allow strategies to be discriminated, and a need for determinism, so that it is worth subjects’ investment of effort to exploit the contingencies optimally. We show through simulation that under certain conditions model-free strategies can masquerade as being model-based. We first show that seemingly innocuous modifications to the task structure can induce correlations between action values at the start of the trial and the subsequent trial events in such a way that analysis based on comparing successive trials can lead to erroneous conclusions. We confirm the power of a suggested correction to the analysis that can alleviate this problem. We then consider model-free reinforcement learning strategies that exploit correlations between where rewards are obtained and which actions have high expected value. These generate behaviour that appears model-based under these, and also more sophisticated, analyses. Exploiting the full potential of the two-step task as a tool for behavioural neuroscience requires an understanding of these issues.     

Acoustic Aposematism and Evasive Action in Select Chemically Defended Arctiine (Lepidoptera: Erebidae) Species: Nonchalant or Not?

Tiger moths (Erebidae: Arctiinae) have experienced intense selective pressure from echolocating, insectivorous bats for over 65 million years. One outcome has been the evolution of acoustic signals that advertise the presence of toxins sequestered from the moths’ larval host plants, i.e. acoustic aposematism. Little is known about the effectiveness of tiger moth anti-bat sounds in their natural environments. We used multiple infrared cameras to reconstruct bat-moth interactions in three-dimensional (3-D) space to examine how functional sound-producing organs called tymbals affect predation of two chemically defended tiger moth species: Pygarctia roseicapitis (Arctiini) and Cisthene martini (Lithosiini). P. roseicapitis and C. martini with intact tymbals were 1.8 and 1.6 times less likely to be captured by bats relative to those rendered silent. 3-D flight path and acoustic analyses indicated that bats actively avoided capturing sound-producing moths. Clicking behavior differed between the two tiger moth species, with P. roseicapitis responding in an earlier phase of bat attack. Evasive flight behavior in response to bat attacks was markedly different between the two tiger moth species. P. roseicapitis frequently paired evasive dives with aposematic sound production. C. martini were considerably more nonchalant and employed evasion in fewer interactions. Our results show that acoustic aposematism is effective at deterring bat predation in a natural context and that this strategy is likely to be the ancestral function of tymbal organs within the Arctiinae.     

Are Dogs Children,Companions, or Just Animals? Understanding Variations in People's Orientations toward Animals

ABSTRACT

This paper examines the variations in dog owners' attitudes toward, treatment of, and interactions with, animals. Based on 28 in-depth interviews with dog owners from a county in the Midwestern United States, I demonstrate that pets are an important part of many people's lives, often providing companionship, entertainment, and meaningful interactions; however, there are notable, distinct variations in how people relate to them. Pet owners typically exhibit one of three orientations toward pets: “dominionistic,” “humanistic,” or “protectionistic.” The dominionistic have relatively low regard for their pets, valuing them primarily for the uses they provide, such as protection. Those employing the humanistic orientation elevate their pets to the status of surrogate humans and value their pets primarily for the affective benefits they enjoy from their close attachments. The protectionistic have high regard for both pets and animals more generally. They view pets as valuable companions and as creatures with their own interests. This typology offers insights for understanding the source and variety of the often ambiguous and contradictory relations between people and pets. I argue that individual characteristics and experiences impact how people understand and relate to animals, in large part, because they represent exposure to different cultural messages. I suggest that these orientations represent three sets of distinct cultural logics, each with distinct histories and contemporary sources.     

CROP – The Clinico-Radiologico-Ophthalmological Paradox in Multiple Sclerosis: Are Patterns of Retinal and MRI Changes Heterogeneous and Thus Not Predictable?

Background

To date, no direct scientific evidence has been found linking tissue changes in multiple sclerosis (MS) patients, such as demyelination, axonal destruction or gliosis, with either steady progression and/or stepwise accumulation of focal CNS lesions. Tissue changes such as reduction of the retinal nerve fiber layer (RNFL) and the total macular volume (TMV), or brain- and spinal cord atrophy indicates an irreversible stage of tissue destruction. Whether these changes are found in all MS patients, and if there is a correlation with clinical disease state, remains controversial. The objective of our study was to determine, whether there was any correlation between the RNFL or TMV of patients with MS, and: (1) the lesion load along the visual pathways, (2) the ratios and absolute concentrations of metabolites in the normal-appearing white matter (NAWM), (3) standard brain atrophy indices, (4) disease activity or (5) disease duration.

Methods

28 MS patients (RRMS, n = 23; secondary progressive MS (SPMS), n = 5) with moderately-high disease activity or long disease course were included in the study. We utilised: (1) magnetic resonance imaging (MRI) and (2) -spectroscopy (MRS), both operating at 3 Tesla, and (3) high-resolution spectral domain-OCT with locked reference images and eye tracking mode) to undertake the study.

Results

There was no consistency in the pattern of CNS metabolites, brain atrophy indices and the RNFL/TMV between individuals, which ranged from normal to markedly-reduced levels. Furthermore, there was no strict correlation between CNS metabolites, lesions along the visual pathways, atrophy indices, RNFL, TMV, disease duration or disability.

Conclusions

Based on the findings of this study, we recommend that the concept of ‘clinico-radiologico paradox’ in multiple sclerosis be extended to CROP–‘clinico-radiologico-ophthalmological paradox’. Furthermore, OCT data of MS patients should be interpreted with caution.     

Are Limestone Hills a Refuge or Essential Habitat for White-Headed Langurs in Fusui,China?

We studied the ecology of white-headed langurs (Trachypithecus leucocephalus) in Fusui Precious Animal Reserve, Guangxi, China, in 1997/1998 and conducted surveys of them in 1996–1997 and 2003. We collected data on vegetation fragments and the activities of white-headed langurs at different levels on limestone hills. The langurs selected less fragmented habitats with less human disturbance. They spent ca. 60% of the day at lower levels of the hills during maintenance activities, including feeding. When humans were absent, the langurs even came to the ground. The hills themselves were used as a refuge from human disturbance but were not otherwise essential habitat. Results of this study have implications for improving conservation management for the langurs.     

Rook Spring Seed Dispersal in the Agricultural Landscape – Frugivory, Granivory or Accidental Transport?

Seed dispersal seems to be extremely important in agrocoenoses where suitable habitats (patches) are surrounded by an unfavourable environment (matrix). The role of the rook Corvus frugilegus, an omnivorous bird, in seed dispersal was studied in the agricultural landscape of Eastern Poland. We analyzed 739 pellets produced by regurgitation, which were collected under breeding colonies in April, May and June. Our goal was to i) assess the structure of the seed pool in pellets; ii) evaluate the temporal variation in the pellet seed pool on two different time scales; iii) compare the species composition of seeds in pellets and vegetation under the rook nests. Seeds were present in 18 % of pellets; 571 seeds were found, half of them belonging to dry-fruited species, without any obvious adaptations to endozoochory. These seeds could be an additional source of food, or they could have been accidentally swallowed during foraging for other food items. Taking into consideration the abundance of the rook population, we assessed the mean number of seeds transferred by one bird to be from 4 seeds per month in April and up to 160 seeds in June. The most important factor responsible for qualitative and quantitative structure of seed pool in pellets is the time when pellets were regurgitated. The type and availability of food determines the number and species structure of dispersed seeds. The comparison of the species structure of the seed pool in pellets and of the herb layer under the breeding colonies showed that the rook could effectively disperse seeds of weeds, meadow and ruderal species, that could germinate under the dense canopy of trees at the studied sites.     

Apoptosis in Activated T Cells – What Are the Triggers,and What the Signal Transducers?

At the end of an immune response, apoptosis drastically reduces the numbers of activated T cells. It has been a matter of intense research how this form of apoptosis is regulated and initiated, and a number of proteins have been identified that contribute to this process. The present, widely accepted model assumes that the interplay of pro- and anti-apoptotic Bcl-2 family members determines the onset of activated T cell death, with the BH3-only protein Bim activating pro-apoptotic Bax/Bak. In the search for up-stream signals, factors from other immune cells have been shown to play a role, and the NF-κB family member Bcl-3 has been implicated as a signalling-intermediate in T cells. Recent work has tested the interrelation of these factors and has suggested that Bcl-3 acts as a regulator of Bim activation, that the induction of apoptosis through Bim can be complemented by its relative Puma, and that the presence of certain cytokines during T cell activation delays the activation of Bim and Puma. Here we discuss these recent insights and provide a view on how the regulation of activated T cell death is achieved and how extrinsic signals may translate into the activation of the apoptotic pathway.     

Enhanced Activation of Memory,but Not Na?ve,B Cells in Chronic Hepatitis C Virus-Infected Patients with Cryoglobulinemia and Advanced Liver Fibrosis

Mixed cryoglobulinemia is the most common extrahepatic disease manifestation of chronic hepatitis C virus (HCV) infection, where immunoglobulins precipitate at low temperatures and cause symptoms such as vasculitis, glomerulonephritis and arthralgia. HCV-associated cryoglobulinemia is also strongly linked with the development of B cell non-Hodgkin lymphoma. Abnormal B cell function in HCV infections can lead to the formation of HCV cryoglobulin complexes that usually comprise monoclonal rheumatoid factor and HCV-specific immune complexes. The aim of this study was to characterize the activation phenotype of B cells from patients with chronic HCV infection in comparison to healthy controls using flow cytometry. In addition, we determined how the activation status varies depending on the presence of cryoglobulinemia and advanced liver fibrosis. We found that only memory B cells, not naïve cells, were significantly activated in chronic HCV infection when compared with healthy controls. We also identified markers of memory B cell activation that were specific for HCV patients with cryoglobulinemia (CD86, CD71, HLA-DR) and advanced liver disease (CD86). Our results demonstrate that HCV infection has differential effects on B cells depending on the severity of hepatic and extrahepatic disease.     

Trends in Prevalence of Overweight and Obesity in Danish Infants,Children and Adolescents – Are We Still on a Plateau?

Background

After the worldwide steep increase in child and adolescent overweight and obesity during the last decades, there is now evidence of a levelling off in the prevalence in many countries in the Western world.

Aim

To examine whether there still is a plateau in the prevalence of overweight and obesity in Danish children and adolescents, or whether the prevalence is decreasing or rising again.

Methods

The trends in the prevalence rates were based on three data sets providing comparable repeated estimates: 1) the Danish Health Visitors Child Health Database (DHVCHD) with measurements on infant and childhood height and weight from 2002 to 2011 (n up to 39,984), 2) the Danish National Birth Cohort (DNBC) with maternal reports of measured infant and childhood height and weight from 1998 to 2010 (n up to 56,826) and 3) the Danish part of the Health Behaviour in School-aged Children survey (HBSC) with self-reported information on adolescent height and weight from the years 2002 to 2010 (n = 16,557). Overweight and obesity were categorized according to WHO growth standards. Trends were assessed by repeated point estimates and linear regression analyses providing regression coefficients for changes in per cent per year with 95% confidence intervals (CI).

Results

The prevalence rates of overweight and obesity for infants, children and adolescents showed a mixed pattern of decline, stability and increase (ranging from -1.10 through 0.29 per cent per year with CI’s from -3.10 through 2.37). Overall, there were no consistent statistically significant trends upwards or downwards, although some significant downward trends in childhood and adolescence were observed.

Conclusion

This study, based on data from 1998 through 2011, showed that the prevalence rates of overweight and obesity among Danish infants, children and adolescents were largely still on a plateau with tendencies for a decline among children and adolescents.     

Hatching from the sediment egg-bank,or aerial dispersing? – the use of mesocosms in assessing rotifer biodiversity

Rotifer emergence from dry billabong sediments was studied from 3 sites on the River Murray floodplain, near Wodonga, northern Victoria, Australia. The sites had different flood histories, ranging from annual to approximately 25-year flooding intervals. Half of each sediment type was sterilized by -radiation to contrast the contribution of recruitment from the egg bank with recruitment from passive dispersal. A series of mesocosms was employed to assess differences between treatments, i.e. sediment sterilization and flood history. Analysis by Canonical Correspondence Analysis and Similarity Percentages suggested that some species were passively dispersed. Of the 54 species colonizing after 35 days, four were undescribed, one was a new record to Australia, three species had previously been recorded only from Tasmania and five more were new to the study area. Overall, 22% of species were previously unrecorded from the study area. This suggests that habitat poor mesocosms, may be more successful in locating passively dispersed taxa than examination of natural temporary waters.     

Commensal Bacteria and MAMPs Are Necessary for Stress-Induced Increases in IL-1β and IL-18 but Not IL-6, IL-10 or MCP-1

Regular interactions between commensal bacteria and the enteric mucosal immune environment are necessary for normal immunity. Alterations of the commensal bacterial communities or mucosal barrier can disrupt immune function. Chronic stress interferes with bacterial community structure (specifically, α-diversity) and the integrity of the intestinal barrier. These interferences can contribute to chronic stress-induced increases in systemic IL-6 and TNF-α. Chronic stress, however, produces many physiological changes that could indirectly influence immune activity. In addition to IL-6 and TNF-α, exposure to acute stressors upregulates a plethora of inflammatory proteins, each having unique synthesis and release mechanisms. We therefore tested the hypothesis that acute stress-induced inflammatory protein responses are dependent on the commensal bacteria, and more specifically, lipopolysaccharide (LPS) shed from Gram-negative intestinal commensal bacteria. We present evidence that both reducing commensal bacteria using antibiotics and neutralizing LPS using endotoxin inhibitor (EI) attenuates increases in some (inflammasome dependent, IL-1 and IL-18), but not all (inflammasome independent, IL-6, IL-10, and MCP-1) inflammatory proteins in the blood of male F344 rats exposed to an acute tail shock stressor. Acute stress did not impact α- or β- diversity measured using 16S rRNA diversity analyses, but selectively reduced the relative abundance of Prevotella. These findings indicate that commensal bacteria contribute to acute stress-induced inflammatory protein responses, and support the presence of LPS-mediated signaling in stress-evoked cytokine and chemokine production. The selectivity of the commensal bacteria in stress-evoked IL-1β and IL-18 responses may implicate the inflammasome in this response.     

Are color or high rearing density related to migratory polyphenism in the band-winged grasshopper, Oedaleus asiaticus?

Locusts represent an impressive example of migratory polyphenism, with high densities triggering a switch from a solitarious, shorter dispersal range, and sometimes greenish phenotype to a gregarious and sometimes darker form exhibiting behavioral, morphological and physiological traits associated with long-distance migratory swarms. While such polyphenism has been well documented in Locusta migratoria and Schistocerca gregaria, the extent to which other grasshoppers exhibit this type of migratory polyphenism is unclear. Anecdotally, the Chinese grasshopper, Oedaleus asiaticus, forms migratory swarms comprised mostly of a darker, brown-colored morph, but also exhibits a non-migratory green-colored morph that predominates at low densities. In a population in Inner Mongolia not currently exhibiting migratory swarms, we found that while green and brown O. asiaticus are found concurrently across our sampled range, only brown grasshoppers were found in high densities. Differences between field-collected brown and green forms matched some but not key predictions associated with the hypothesis that the brown form is morphologically and physiologically specialized for gregarious migration. Controlling for body mass, brown forms had more massive thoraxes, abdomens and legs, and higher metabolic rates, but not more flight muscle or lipid stores. Further, the brown and green grasshoppers did not differ in gregarious behavior, and neither would fly in multiple lab and field trials. Lab or field-rearing at high densities for one-to-multiple juvenile instars caused grasshoppers to exhibit some morphological traits predicted to benefit migration (larger wings and a shift in relative mass from abdomen to thorax), but did not change color or induce flight behavior. One hypothesis to explain these data is that a migratory form of O. asiaticus is partially triggered by high field densities, but that existing ecological conditions blocked full expression of such traits (and outbreak swarms). Alternatively, color variation in this species may more tightly linked to other functions in this species such as crypsis or disease resistance, and mechanisms other than late-juvenile rearing density (e.g. genetic variation, maternal effects) may be more critical for promoting variation in color and/or migratory polyphenism.