Behavioral Modernity and the Cultural Transmission of Structured Information: The Semantic Axelrod Model

Cultural transmission models are coming to the fore in explaining increases in the Paleolithic toolkit richness and diversity. During the later Paleolithic, technologies increase not only in terms of diversity but also in their complexity and interdependence. As Mesoudi and O'Brien (2008) have shown, selection broadly favors social learning of information that is hierarchical and structured, and multiple studies have demonstrated that teaching within a social learning environment can increase fitness. We believe that teaching also provides the scaffolding for transmission of more complex cultural traits. Here, we introduce an extension of the Axelrod (1997} model of cultural differentiation in which traits have prerequisite relationships, and where social learning is dependent upon the ordering of those prerequisites. We examine the resulting structure of cultural repertoires as learning environments range from largely unstructured imitation, to structured teaching of necessary prerequisites, and we find that in combination with individual learning and innovation, high probabilities of teaching prerequisites leads to richer cultural repertoires. Our results point to ways in which we can build more comprehensive explanations of the archaeological record of the Paleolithic as well as other cases of technological change.Comment: 24 pages, 7 figures. Submitted to "Learning Strategies and Cultural Evolution during the Paleolithic", edited by Kenichi Aoki and Alex Mesoudi, and presented at the 79th Annual Meeting of the Society for American Archaeology, Austin TX. Revised 5/14/1

The functional brain networks that underlie Early Stone Age tool manufacture

After 800,000 years of making simple Oldowan tools, early humans began manufacturing Acheulian handaxes around 1.75 million years ago. This advance is hypothesized to reflect an evolutionary change in hominin cognition and language abilities. We used a neuroarchaeology approach to investigate this hypothesis, recording brain activity using functional near-infrared spectroscopy as modern human participants learned to make Oldowan and Acheulian stone tools in either a verbal or nonverbal training context. Here we show that Acheulian tool production requires the integration of visual, auditory and sensorimotor information in the middle and superior temporal cortex, the guidance of visual working memory representations in the ventral precentral gyrus, and higher-order action planning via the supplementary motor area, activating a brain network that is also involved in modern piano playing. The right analogue to Broca’s area—which has linked tool manufacture and language in prior work1,2—was only engaged during verbal training. Acheulian toolmaking, therefore, may have more evolutionary ties to playing Mozart than quoting Shakespeare

INvestigational Vertebroplasty Efficacy and Safety Trial (INVEST): a randomized controlled trial of percutaneous vertebroplasty

Background: The treatment of painful osteoporotic vertebral compression fractures has historically been limited to several weeks of bed rest, anti-inflammatory and analgesic medications, calcitonin injections, or external bracing. Percutaneous vertebroplasty (the injection of bone cement into the fractured vertebral body) is a relatively new procedure used to treat these fractures. There is increasing interest to examine the efficacy and safety of percutaneous vertebroplasty and to study the possibility of a placebo effect or whether the pain relief is from local anesthetics placed directly on the bone during the vertebroplasty procedure. Methods/Designs: Our goal is to test the hypothesis that patients with painful osteoporotic vertebral compression fractures who undergo vertebroplasty have less disability and pain at 1 month than patients who undergo a control intervention. The control intervention is placement of local anesthesia near the fracture, without placement of cement. One hundred sixty-six patients with painful osteoporotic vertebral compression fractures will be recruited over 5 years from US and foreign sites performing the vertebroplasty procedure. We will exclude patients with malignant tumor deposit (multiple myeloma), tumor mass or tumor extension into the epidural space at the level of the fracture. We will randomly assign participants to receive either vertebroplasty or the control intervention. Subjects will complete a battery of validated, standardized measures of pain, functional disability, and health related quality of life at baseline and at post-randomization time points (days 1, 2, 3, and 14, and months 1, 3, 6, and 12). Both subjects and research interviewers performing the follow-up assessments will be blinded to the randomization assignment. Subjects will have a clinic visit at months 1 and 12. Spine X-rays will be obtained at the end of the study (month 12) to determine subsequent fracture rates. Our co-primary outcomes are the modified Roland score and pain numerical rating scale at 1 month. Discussion: Although extensively utilized throughout North America for palliation of pain, vertebroplasty still has not undergone rigorous study. The study outlined above represents the first randomized, controlled study that can account for a placebo effect in the setting of vertebroplasty. Trial Registration: Current Controlled Trials ISRCTN81871888.The source of funding for the study and all authors for this publication was National Institutes of Health (NIH)/National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)

Evaluation of the Acute Oral Toxicity Class of Trinuclear Chromium(III) Glycinate Complex in Rat

Chromium(III) is considered as an essential element playing a role in carbohydrate and lipid metabolism, and various chemical forms of this element are widely used in dietary supplements. A new trinuclear chromium(III) glycinate complex [Cr3O(NH2CH2CO2)6(H2O)3]+NO3− (CrGly), an analogue of Cr3 (trinuclear Cr(III) propionate complex) has been synthesized as a potential source of supplementary Cr. In this study, we evaluated the acute toxicity class of CrGly in Wistar rats applying the OECD 423 procedure. Male and female Wistar rats (n = 12, 6 ♀ and 6 ♂) were given by gavage either a single dose of CrGly 2,000 mg/kg body mass (equals to 300 mg Cr(III)/kg body mass; in aqueous solution) or equivalent volumes of distilled water and fed ad libitum commercial Labofeed B diet, and observed carefully for 14 days, then sacrificed to collect blood and internal organs for biochemical and histologic examination. No death cases were detected. No abnormalities in animal behavior, body mass gains, gross organ histology, or blood morphology and biochemistry were observed. The results demonstrate that LD50 of CrGly is greater than 2,000 mg/kg when administrated orally to rat; thus, this compound appears to belong to the fifth category in the GHS system or the fourth class (“unclassified”) in the EU classification system

Age-associated impaired plasmacytoid dendritic cell functions lead to decreased CD4 and CD8 T cell immunity

Increased susceptibility to infections, particularly respiratory viral infections, is a hallmark of advancing age. The underlying mechanisms are not well understood, and there is a scarcity of information regarding the contribution of the innate immune system, which is the first line of defense against infections. In the present study, we have investigated the effect of advancing age on plasmacytoid dendritic cell (PDC) function because they are critical in generating a robust antiviral response via the secretion of interferons (IFN). Our results indicate that PDCs from the aged are impaired in their capacity to secrete IFN-I in response to influenza virus and CPG stimulation. Additionally, we observed a severe reduction in the production of IFN-III, which plays an important role in defense against viral infections at respiratory mucosal surfaces. This reduction in IFN-I and IFN-III were a result of age-associated impaired phosphorylation of transcription factor, IRF-7. Furthermore, aged PDCs were observed to be impaired in their capacity to induce perforin and granzyme in CD8 T cells. Comparison of the antigen-presenting capacity of aged PDC with young PDC revealed that PDCs from aged subjects display reduced capacity to induce proliferation and IFN-gamma secretion in CD4 and CD8 T cells as compared with PDCs from young subjects. In summary, our study demonstrates that advancing age has a profound effect on PDC function at multiple levels and may therefore, be responsible for the increased susceptibility to infections in the elderly

Cognitive and cognitive-motor interventions affecting physical functioning: A systematic review

Background Several types of cognitive or combined cognitive-motor intervention types that might influence physical functions have been proposed in the past: training of dual-tasking abilities, and improving cognitive function through behavioral interventions or the use of computer games. The objective of this systematic review was to examine the literature regarding the use of cognitive and cognitive-motor interventions to improve physical functioning in older adults or people with neurological impairments that are similar to cognitive impairments seen in aging. The aim was to identify potentially promising methods that might be used in future intervention type studies for older adults. Methods A systematic search was conducted for the Medline/Premedline, PsycINFO, CINAHL and EMBASE databases. The search was focused on older adults over the age of 65. To increase the number of articles for review, we also included those discussing adult patients with neurological impairments due to trauma, as these cognitive impairments are similar to those seen in the aging population. The search was restricted to English, German and French language literature without any limitation of publication date or restriction by study design. Cognitive or cognitive-motor interventions were defined as dual-tasking, virtual reality exercise, cognitive exercise, or a combination of these. Results 28 articles met our inclusion criteria. Three articles used an isolated cognitive rehabilitation intervention, seven articles used a dual-task intervention and 19 applied a computerized intervention. There is evidence to suggest that cognitive or motor-cognitive methods positively affects physical functioning, such as postural control, walking abilities and general functions of the upper and lower extremities, respectively. The majority of the included studies resulted in improvements of the assessed functional outcome measures. Conclusions The current evidence on the effectiveness of cognitive or motor-cognitive interventions to improve physical functioning in older adults or people with neurological impairments is limited. The heterogeneity of the studies published so far does not allow defining the training methodology with the greatest effectiveness. This review nevertheless provides important foundational information in order to encourage further development of novel cognitive or cognitive-motor interventions, preferably with a randomized control design. Future research that aims to examine the relation between improvements in cognitive skills and the translation to better performance on selected physical tasks should explicitly take the relation between the cognitive and physical skills into account.ISSN:1471-231

The Changing Face of Neolithic and Bronze Age Ireland: A Big Data Approach to the Settlement and Burial Records

This paper synthesizes and analyses the spatial and temporal patterns of archaeological sites in Ireland spanning the Neolithic period and the Bronze Age transition (4300-1900 cal BC). Included are a large number of unpublished, newly discovered sites excavated through development-led projects. Data were also sourced from national archives, published excavation reports and on-line databases. Software tools were developed to deal with the varying nature and resolution of these datasets, allowing chronology to be considered in the analysis to a degree that is usually not possible in prehistoric studies. Summed radiocarbon probabilities are used to examine the dataset using context- and sample-sensitive approaches. Visualisations of spatial and chronological data illustrate the expansion of Early Neolithic settlement, followed by an apparent attenuation of all settlement activity. The Late Neolithic and Chalcolithic periods are characterised by a resurgence and diversification of activity. To assess the significance of these observations, Irish radiocarbon data are compared to an idealized model derived from North American data. Even after taking various considerations into account, human population increases can be suggested to have occurred during the Early and Late Neolithic periods. Gaps and biases in the data are discussed and priorities for future work are identified

Mechanomyographic amplitude and frequency responses during dynamic muscle actions: a comprehensive review

The purpose of this review is to examine the literature that has investigated mechanomyographic (MMG) amplitude and frequency responses during dynamic muscle actions. To date, the majority of MMG research has focused on isometric muscle actions. Recent studies, however, have examined the MMG time and/or frequency domain responses during various types of dynamic activities, including dynamic constant external resistance (DCER) and isokinetic muscle actions, as well as cycle ergometry. Despite the potential influences of factors such as changes in muscle length and the thickness of the tissue between the muscle and the MMG sensor, there is convincing evidence that during dynamic muscle actions, the MMG signal provides valid information regarding muscle function. This argument is supported by consistencies in the MMG literature, such as the close relationship between MMG amplitude and power output and a linear increase in MMG amplitude with concentric torque production. There are still many issues, however, that have yet to be resolved, and the literature base for MMG during both dynamic and isometric muscle actions is far from complete. Thus, it is important to investigate the unique applications of MMG amplitude and frequency responses with different experimental designs/methodologies to continually reassess the uses/limitations of MMG