Quantum Leaps in Human Biocultural Evolution and the Relationship to Cranial Capacity.

The evolution of the genus Homo can only be understood by considering both of the inheritance systems that interact to shape human nature: biology and culture. While growing intellectual abilities are a key factor of human evolution, they are rarely contrasted with cultural progress. Cranial capacity data of 193 hominin fossils from the last seven million years and artefacts of increasing number and complexity in the archaeological record are used to demonstrate the concordant progression of brain-size increase and cultural development, starting approximately two million years ago. Our biocultural evolution shows a number of quantum leaps along the time axis applying to both domains. At first, humans left the canonical evolutionary pathway, which pertains to all other organisms, by enhancing their fitness using sophisticated tools and fire; secondly, they turned into a symbolic species; and finally, humanity now faces a new challenge: "intentional evolution". Chronologically, these quantum leaps correspond to cranial capacity data used here as a proxy for cognitive performance. This contribution tries to demonstrate this parallel development and argues for a simple and generalized model of human biocultural evolution. An extrapolation of the model into the future shows that humans, as biological entities, will not necessarily persist.

Computational models of stimulus equivalence: An intersection for the study of symbolic behavior.

Stimulus equivalence is a central paradigm in the analysis of symbolic behavior, language, and cognition. It describes emergent relations between stimuli that were not explicitly trained and cannot be explained by primary stimulus generalization. In recent years, researchers have developed computational models to simulate the learning of equivalence relations. These models have been used to address primary theoretical and methodological issues in this field, such as exploring the underlying mechanisms that explain emergent equivalence relations and analyzing the effects of training and testing protocols on equivalence outcomes. Nonetheless, although these models build upon general learning principles, their operation is usually obscure for nonmodelers, and in the field of stimulus equivalence computational models have been developed with a variety of approaches, architectures, and algorithms that make it difficult to understand the scope and contributions of these tools. In this paper, we present the state of the art in computational modeling of stimulus equivalence. We seek to provide concise and accessible descriptions of the models' functioning and operation, highlight their main theoretical and methodological contributions, identify the existing software available for researchers to run experiments, and suggest future directions in the emergent field of computational modeling of stimulus equivalence.

Personal ornaments from Hayonim and Manot caves (Israel) hint at symbolic ties between the Levantine and the European Aurignacian.

Situated at the crossroads of Africa and Eurasia, the Levant is a crucial region for understanding the origins and spread of Upper Paleolithic (UP) traditions associated with the spread of modern humans. Of the two local Early Upper Paleolithic technocomplexes, the Ahmarian and the Levantine Aurignacian, the latter appears to be unique in the endemic UP sequence, exhibiting greater similarity to the West European 'classic' Aurignacian than to the local preceding and proceeding UP entities. Previous publications have mostly focused on the similarities between the two lithic industries and less on studies conducted on Levantine Aurignacian bone tools and ornaments. Here, we present an archaeozoological, technological and use-wear study of ornaments on animal teeth from the Levantine Aurignacian layers at Manot and Hayonim caves (the Galilee, Israel). The selection of taxa, the choice of teeth, the mode of modification, and the use-wear analysis exhibit clear similarities with the European Aurignacian. This, with the technology of the osseous raw material exploitation, the presence of antler simple-base points, and some lithic typotechnological features, suggest a link between the symbolic spheres of the Levantine and the European Aurignacian cultural entities. Such similarity also supports some contribution of European Aurignacians groups to the local cultural entities, intermingling with the local material culture features.

Early anthropogenic use of hematite on Aurignacian ivory personal ornaments from Hohle Fels and Vogelherd caves, Germany.

The Aurignacian (ca. 43-35 ka) of southwestern Germany is well known for yielding some of the oldest artifacts related to symbolic behaviors, including examples of figurative art, musical instruments, and personal ornaments. Another aspect of these behaviors is the presence of numerous pieces of iron oxide (ocher); however, these are comparatively understudied, likely owing to the lack of painted artifacts from this region and time period. Several Aurignacian-aged carved ivory personal ornaments from the sites of Hohle Fels and Vogelherd contain traces of what appear to be red ocher residues. We analyzed these beads using a combination of macroanalytical and microanalytical methods, including scanning electron microscopy equipped with energy dispersive spectroscopy and Raman spectroscopy. We found that the residue is composed of the iron oxide mineral hematite (Fe2O3). Further analyses on associated archaeological sediments by X-ray diffraction revealed the absence of hematite and other iron oxide mineral phases, suggesting that the hematite residues were intentionally applied to the ivory personal ornaments by human agents. These findings have important implications as they represent evidence for the direct application of ocher on portable symbolic objects by early Homo sapiens in Europe. Furthermore, our results reveal shared behavioral practices from two key Aurignacian sites maintained over several millennia and illuminate aspects of pigment use and symbolic practices during a pivotal time in the cultural evolution of humans.

Classes de Estímulos por Bebês de até 24 Meses de Idade, / Stimulus Classes to Infants up to 24 Months Old

Resumo Neste estudo investigou-se a emergência de classes de equivalência generalizada, com inclusão de reforçadores específicos em bebês de 24 meses. Relações auditivo-visuais (AB e AC) foram ensinadas, com consequências específicas (D), para 5 bebês entre 18 e 20 meses de idade. Testes de nomeação e de relações emergentes foram realizados (BC, CB, AD, DE e EB, com semelhança física dos estímulos E e B). Três participantes formaram de classes de equivalência, incluindo os reforçadores específicos (ABCD), e dois deles apresentaram nomeação consistente. Dois participantes apresentaram desempenho correspondente à equivalência generalizada. Os resultados indicaram (a) a inédita formação de classes de equivalência generalizada com inclusão de reforçadores específicos em bebês, e (b) que a nomeação pode não ser condição necessária para a formação de classes.

Abstract This study assessed the emergence of generalized equivalence classes, with the inclusion of specific reinforcers, by infants up to 24 months old. Auditory-visual relations (AB and AC) were taught, with specific consequences (D), for five infants aged between 18 and 20 months. Naming and emergent relations tests (BC, CB, AD, DE and EB, with B and E stimuli physically similar). Three participants demonstrated equivalence classes formation, including specific reinforcers (ABCD), and two of them presented consistent naming. Two participants demonstrated generalized equivalence classes. The results indicated the unprecedented formation of generalized equivalence classes with the inclusion of specific reinforcers in babies, and that naming may not be a necessary condition for the formation of classes.

Using generalizability theory to evaluate the comparative reliability of developmental measures in neurogenetic syndrome and low-risk populations.

BACKGROUND: The lack of available measures that can reliably characterize early developmental skills in children with neurogenetic syndromes (NGS) poses a significant challenge for research on early development in these populations. Although syndrome-specific measures may sometimes be necessary, a more cost- and time-efficient solution would be to identify existing measures that are appropriate for use in special populations or optimize existing measures to be used in these groups. Reliability is an important metric of psychometric rigor to consider when auditing and optimizing assessment tools for NGS. In this study, we use Generalizability Theory, an extension of classical test theory, as a novel approach for more comprehensively characterizing the reliability of existing measures and making decisions about their use in the field of NGS research. METHODS: We conducted generalizability analyses on a popular early social communication screener, the Communication and Symbolic Behavior Scales-Infant-Toddler Checklist (CSBS-ITC), collected on 172 children (41 Angelman syndrome, 30 Prader-Willi syndrome, 42 Williams syndrome, 59 low-risk controls). RESULTS: Overall, the CSBS-ITC demonstrated at least adequate reliability in the NGS groups included in this study, particularly for the Prader-Willi and Williams syndrome groups. However, the sources of systematic error variance in the CSBS-ITC varied greatly between the low-risk control and NGS groups. Moreover, as unassessed in previous research, the CSBS-ITC demonstrated substantial differences in variance sources among the NGS groups. Reliability of CSBS-ITC scores was highest when averaging across all measurement points for a given child and was generally similar or better in the NGS groups compared to the low-risk control group. CONCLUSIONS: Our findings suggest that the CSBS-ITC communicates different information about the reliability of stability versus change, in low-risk control and NGS samples, respectively, and that psychometric approaches like Generalizability Theory can provide more complete information about the reliability of existing measures and inform decisions about how measures are used in research on early development in NGS.

The evolution of early symbolic behavior in Homo sapiens.

How did human symbolic behavior evolve? Dating up to about 100,000 y ago, the engraved ochre and ostrich eggshell fragments from the South African Blombos Cave and Diepkloof Rock Shelter provide a unique window into presumed early symbolic traditions of Homo sapiens and how they evolved over a period of more than 30,000 y. Using the engravings as stimuli, we report five experiments which suggest that the engravings evolved adaptively, becoming better-suited for human perception and cognition. More specifically, they became more salient, memorable, reproducible, and expressive of style and human intent. However, they did not become more discriminable over time between or within the two archeological sites. Our observations provide support for an account of the Blombos and Diepkloof engravings as decorations and as socially transmitted cultural traditions. By contrast, there was no clear indication that they served as denotational symbolic signs. Our findings have broad implications for our understanding of early symbolic communication and cognition in H. sapiens.

Emotional Faces in Symbolic Relations: A Happiness Superiority Effect Involving the Equivalence Paradigm.

The stimulus equivalence paradigm presented operational criteria to identify symbolic functions in observable behaviors. When humans match dissimilar stimuli (e.g., words to pictures), equivalence relations between those stimuli are likely to be demonstrated through behavioral tests derived from the logical properties of reflexivity, symmetry, and transitivity. If these properties are confirmed, one can say that those stimuli are members of an equivalence class in which each member is substitutable for the others. A number of studies, which have established equivalence classes comprised of arbitrary stimuli and pictures of faces expressing emotions, have found that valences of the faces affect the relatedness of equivalent stimuli. Importantly, several studies reported stronger relational strength in equivalence classes containing happy faces than in equivalence classes containing angry faces. The processes that may account for this higher degree of relatability of happy faces are not yet known. The current study investigated the dynamics of the symbolic relational responding involving facial expressions of different emotions by means of the Implicit Relational Assessment Procedure (IRAP). Participants were 186 undergraduate students who were taught to establish two equivalence classes, each comprising pictures of faces expressing either happiness (for one class) or a negative emotion (for another class), and meaningless words. The IRAP effect was taken as an index for the relational strength established between equivalent stimuli in the different equivalence classes. The dynamics of arbitrary relational responding in the course of the four IRAP trial types revealed that the participants exhibited a stronger IRAP effect in trials involving the happy faces and a weaker IRAP effect in trials involving the negative faces. These findings indicate that the happy faces had higher impact on the symbolic relational responding than the negative faces. The potential role played by the orienting function of happy vs. negative faces is discussed. By considering other studies that also reported a happiness superiority effect in other contexts, we present converging evidence for the prioritization of positive affect in emotional, categorical, and symbolic processing.

Investigando a Emergência de Relações Equivalentes a partir de Estruturas de Treino Mutuamente Excludentes / Investigating the Emergence of Equivalent Relationships with Mutually Exclusive Training Structures

RESUMO Investigou-se a formação de classes equivalentes a partir de estruturas de treino de discriminações condicionais que correspondem a relações emergentes mutuamente excludentes. Participaram um total de 10 universitários distribuídos em dois experimentos. As relações treinadas foram B1A1, B2A2, B3A3, D1C1, D2C2, D3C3, B1C2, B2C1, B3C3, D1A1, D2A2 e D3A3. Foram testadas as relações AC, CA, BD e DB. O Experimento II diferiu-se do Experimento I por incluir uma revisão das relações de treino. Os resultados sugerem a formação de classes para sete dos 10 participantes, sem diferenças significativas entre os experimentos. Contudo, foram estabelecidas diferentes classes para os participantes de ambos os experimentos, sugerindo que a ordem de treino não foi suficiente para determinar quais classes de equivalência seriam formadas.

ABSTRACT This study investigated equivalence classes formation from conditional discrimination training structures that correspond to mutually exclusive emerging relationships. A total of 10 college students participated in two experiments. Trained relations were B1A1, B2A2, B3A3, D1C1, D2C2, D3C3, B1C2, B2C1, B3C3, D1A1, D2A2 and D3A3. Relations AC, CA, BD and DB were tested. Experiment II differed from Experiment I in that it included a review of training relations. The results indicated class formation for seven of the 10 participants, without significant differences between the experiments. However, different classes were established for the participants of both experiments, suggesting that the training order was not enough to determine which equivalence classes would be formed.

Symbolic emblems of the Levantine Aurignacians as a regional entity identifier (Hayonim Cave, Lower Galilee, Israel).

The Levantine Aurignacian is a unique phenomenon in the local Upper Paleolithic sequence, showing greater similarity to the West European classic Aurignacian than to the local Levantine archaeological entities preceding and following it. Herewith we highlight another unique characteristic of this entity, namely, the presence of symbolic objects in the form of notched bones (mostly gazelle scapulae) from the Aurignacian levels of Hayonim Cave, Lower Galilee, Israel. Through both macroscopic and microscopic analyses of the items, we suggest that they are not mere cut marks but rather are intentional (decorative?) human-made markings. The significance of this evidence for symbolic behavior is discussed in its chrono-cultural and geographical contexts. Notched bones are among the oldest symbolic expressions of anatomically modern humans. However, unlike other Paleolithic sites where such findings were reported in single numbers, the number of these items recovered at Hayonim Cave is sufficient to assume they possibly served as an emblem of the Levantine Aurignacian.

Pivotal behavior as the mediator of the relationship between parental responsiveness and children's symbolic behavior.

Previous research with parents and children with developmental disabilities indicated that the relationship between mothers' responsive style of interaction and children's rate of development was mediated by the simultaneous relationship between mothers' responsiveness and children's social engagement, or pivotal behavior. In this study, we attempted to determine whether children's pivotal behavior might also mediate the relationship between responsiveness and child development in a sample of 165 typically developing toddlers and their Taiwanese parents. Child development was assessed with a parent report measure of children's symbolic behavior. Parental responsiveness and children's pivotal behavior were assessed from observations of parent-child play. Results indicated that parental responsiveness was correlated with children's pivotal behavior, and that both of these variables were correlated with children's symbolic behavior. Structural equation models indicated that the relationship between responsiveness and children's symbolic behavior was fully mediated by children's pivotal behavior.

A possible role of the Infant/Toddler Sensory Profile in screening for autism: a proof-of-concept study in the specific sample of prematurely born children with birth weights <1,500 g.

OBJECTIVE: The objective of this study was to explore the potential of the Infant/Toddler Sensory Profile (ITSP) as a screening tool for autism spectrum disorders (ASD) in prematurely born children. METHODS: Parents of 157 children with birth weights <1,500 g (aged 2 years, corrected for prematurity; 88 boys, 69 girls) completed a screening battery that included the ITSP, Modified Checklist for Autism in Toddlers (M-CHAT), and the Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC). Children with known disabilities were excluded. All the children who were screened positive on any of the screening tools subsequently underwent clinical examination including the Autism Diagnostic Observation Schedule. RESULTS: We used classification trees to answer the question whether ITSP (or some of its subscales) could be combined with the M-CHAT and/or the CSBS-DP-ITC or its subscales into an effective ASD screening tool. Using the CSBS-DP-ITC, overall score, and the Sensation Seeking subscale of the ITSP, we obtained a screening tool that was able to identify all of the ASD children in our sample (confirmed by cross-validation). The proposed screening tool is scored as follows: 1) if the overall CSBS-DP-ITC value is <45.5, then the screening is positive; 2) if the overall CSBS-DP-ITC value is ≥45.5 and the z-score of the Sensation Seeking subscale of ITSP is ≥1.54, then the screening is positive; 3) otherwise, the screening is negative. CONCLUSION: The use of CSBS-DP-ITC in combination with the Sensation Seeking subscale of the ITSP improved the accuracy of autism screening in preterm children.

Performance of South African children on the Communication and Symbolic Behavior Scales-Developmental Profile (CSBS DP).

BACKGROUND: Substantial development in social communication skills occurs in the first two years of life. Growth should be evident in sharing emotion and eye gaze; rate of communication, communicating for a variety of functions; using gestures, sounds and words; understanding language, and using functional and pretend actions with objects in play. A delay in these early social communication skills may be the first sign of a developmental delay in young children in nearly all categories of disabilities-including specific language impairment, autism spectrum disorder, HIV/AIDS, lack of environmental stimulation or institutionalization, and global developmental delays-and early detection of these delays is critical for enrolment in appropriate early intervention services. AIMS: No standardized tests of early social communication skills exist for very young children in South Africa (SA). An existing evaluation tool that has the potential to be culturally fair for children from cultural backgrounds different to the standardization group is the Communication and Symbolic Behaviour Scales-Developmental Profile (CSBS DP). This study aimed to document the performance of a group of English-speaking SA children ranging in age from 12 to 24 months on the CSBS DP and to compare this performance with the original standardization sample. METHODS & PROCEDURES: Sixty-seven English-speaking SA children from a range of cultural and linguistic backgrounds were assessed on the CSBS DP Behaviour Sample. Group scores were compared with the original standardization sample using inferential statistics. OUTCOMES & RESULTS: The results provide preliminary support for the suitability and validity of the face-to-face Behaviour Sample as a measure of early social communication skills in this sample of English-speaking SA children from a range of cultural groups between 12 and 24 months of age. CONCLUSIONS & IMPLICATIONS: While further research in the SA population is needed, these findings are a first step towards validating a culturally appropriate measure for early detection of social communication delays in a sample of SA toddlers.

Safety and Efficacy of Cerebrolysin in Infants with Communication Defects due to Severe Perinatal Brain Insult: A Randomized Controlled Clinical Trial.

BACKGROUND AND PURPOSE: The neuroregenerative drug Cerebrolysin has demonstrated efficacy in improving cognition in adults with stroke and Alzheimer's disease. The aim of this study was to determine the efficacy and safety of Cerebrolysin in the treatment of communication defects in infants with severe perinatal brain insult. METHODS: A randomized placebo-controlled clinical trial was conducted in which 158 infants (age 6-21 months) with communication defects due to severe perinatal brain insult were enrolled; 120 infants completed the study. The Cerebrolysin group (n=60) received twice-weekly Cerebrolysin injections of 0.1 mL/kg body weight for 5 weeks (total of ten injections). The placebo group (n=60) received the same amount and number of normal saline injections. RESULTS: The baseline Communication and Symbolic-Behavior-Scale-Developmental Profile scores were comparable between the two groups. After 3 months, the placebo group exhibited improvements in the social (p<0.01) and speech composite (p=0.02) scores, with 10% and 1.5% increases from baseline, respectively. The scores of the Cerebrolysin group changed from concern to no concern, with increases of 65.44%, 45.54%, 358.06%, and 96.00% from baseline in the social (p<0.001), speech (p<0.001), symbolic (p<0.001), and total (p<0.001) scores. CONCLUSIONS: Cerebrolysin dramatically improved infants' communication especially symbolic behavior which positively affected social interaction. These findings suggest that cerebrolysin may be an effective and feasible way equivalent to stem cell therapy.

Safety and Efficacy of Cerebrolysin in Infants with Communication Defects due to Severe Perinatal Brain Insult: A Randomized Controlled Clinical Trial

BACKGROUND AND PURPOSE: The neuroregenerative drug Cerebrolysin has demonstrated efficacy in improving cognition in adults with stroke and Alzheimer's disease. The aim of this study was to determine the efficacy and safety of Cerebrolysin in the treatment of communication defects in infants with severe perinatal brain insult. METHODS: A randomized placebo-controlled clinical trial was conducted in which 158 infants (age 6-21 months) with communication defects due to severe perinatal brain insult were enrolled; 120 infants completed the study. The Cerebrolysin group (n=60) received twice-weekly Cerebrolysin injections of 0.1 mL/kg body weight for 5 weeks (total of ten injections). The placebo group (n=60) received the same amount and number of normal saline injections. RESULTS: The baseline Communication and Symbolic-Behavior-Scale-Developmental Profile scores were comparable between the two groups. After 3 months, the placebo group exhibited improvements in the social (p<0.01) and speech composite (p=0.02) scores, with 10% and 1.5% increases from baseline, respectively. The scores of the Cerebrolysin group changed from concern to no concern, with increases of 65.44%, 45.54%, 358.06%, and 96.00% from baseline in the social (p<0.001), speech (p<0.001), symbolic (p<0.001), and total (p<0.001) scores. CONCLUSIONS: Cerebrolysin dramatically improved infants' communication especially symbolic behavior which positively affected social interaction. These findings suggest that cerebrolysin may be an effective and feasible way equivalent to stem cell therapy.

Efeito do ensino de sentenças sobre a leitura recombinativa com compreensão: procedimento de CRMTS / Effects of the teaching of sentences on recombinative reading with comprehension: CRMTS procedure

O objetivo deste estudo foi investigar o efeito do ensino de sentenças, por meio do procedimento de escolha de acordo com o modelo com resposta construída (CRMTS), sobre a leitura recombinativa com compreensão. Participaram cinco escolares. Inicialmente as relações AB - e AE foram ensinadas e as relações BE/EB testadas. Posteriormente, houve o ensino das relações CB e DB e do teste da relação C’B. Finalmente, a relação FB foi ensinada e as relações FB’, DC e CD testadas. A letra A representa a classe das palavras faladas, B palavras impressas, C sentenças impressas, D sentenças ditadas, E figuras, F cores, B’ palavras impressas novas e C’ sentenças impressas novas. Todos os participantes aprenderam as relações ensinadas. Três participantes responderam com 100% de acerto aos testes BE, EB e C’B e todos responderam com 100% de acerto aos testes FB’, DC e CD. Os resultados sugerem que o procedimento foi efetivo em gerar leitura recombinativa generalizada e leitura com compreensão das sentenças. (AU)

The objective of this study was to investigate the effects of the teaching of sentences using the constructed response matching to sample procedure (CRMTS) on recombinative reading with comprehension. Participants were five children from the Basic Education. First relations AB and AE were taught and the relations BE/EB tested. After, there was the teaching of CB and DB relations and the test of C’B relation. Finally, the relations FB was taught and the relations FB’, DC and CD were tested. The letter A represents the class of the spoken word, B printed word, C printedsentence, D spoken sentences, E figure, F colors, B’ new printed words and C’ new printed sentences. All participants learned the taught relations. Three participants had 100% of correct responses in the BE, EB and C’B tests and all of them had 100% of correct responses in the FB’, DC and CD tests. The results suggest that the procedure was effective in generate generalized recombinative reading and reading with comprehension. (AU)

Efeito do ensino de sentenças sobre a leitura recombinativa com compreensão: procedimento de CRMTS / Effects of the teaching of sentences on recombinative reading with comprehension: CRMTS procedure

O objetivo deste estudo foi investigar o efeito do ensino de sentenças, por meio do procedimento de escolha de acordo com o modelo com resposta construída (CRMTS), sobre a leitura recombinativa com compreensão. Participaram cinco escolares. Inicialmente as relações AB - e AE foram ensinadas e as relações BE/EB testadas. Posteriormente, houve o ensino das relações CB e DB e do teste da relação C’B. Finalmente, a relação FB foi ensinada e as relações FB’, DC e CD testadas. A letra A representa a classe das palavras faladas, B palavras impressas, C sentenças impressas, D sentenças ditadas, E figuras, F cores, B’ palavras impressas novas e C’ sentenças impressas novas. Todos os participantes aprenderam as relações ensinadas. Três participantes responderam com 100% de acerto aos testes BE, EB e C’B e todos responderam com 100% de acerto aos testes FB’, DC e CD. Os resultados sugerem que o procedimento foi efetivo em gerar leitura recombinativa generalizada e leitura com compreensão das sentenças.

The objective of this study was to investigate the effects of the teaching of sentences using the constructed response matching to sample procedure (CRMTS) on recombinative reading with comprehension. Participants were five children from the Basic Education. First relations AB and AE were taught and the relations BE/EB tested. After, there was the teaching of CB and DB relations and the test of C’B relation. Finally, the relations FB was taught and the relations FB’, DC and CD were tested. The letter A represents the class of the spoken word, B printed word, C printedsentence, D spoken sentences, E figure, F colors, B’ new printed words and C’ new printed sentences. All participants learned the taught relations. Three participants had 100% of correct responses in the BE, EB and C’B tests and all of them had 100% of correct responses in the FB’, DC and CD tests. The results suggest that the procedure was effective in generate generalized recombinative reading and reading with comprehension.

Comparison of three screening tests for autism in preterm children with birth weights less than 1,500 grams.

BACKGROUND: Preterm children seem to be at increased risk for autism spectrum disorders (ASD). METHODS: Parents of 157 children with birth weights less than 1,500 g (age 2 years, corrected for prematurity; 88 boys, 69 girls) completed screening questionnaires. The screening battery included the Modified Checklist for Autism in Toddlers (M-CHAT), Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS-DP-ITC), and the Infant/Toddler Sensory Profile (ITSP). Children with disabilities were excluded. All children who screened positive on any of the screening tools were subsequently assessed by clinical examination including the Autism Diagnostic Observation Schedule. RESULTS: Fifty-six children (35.7%) screened positive on at least one of the parental screening questionnaires. Of the 56 children who tested positive, 33 participated in the detailed clinical follow-up assessment. A diagnosis of ASD was confirmed in 13 of the 33 children. The ASD prevalence was 9.7% of the sample. Analysis of children with and without an ASD diagnosis found significant differences relative to gestational age (26.9 weeks vs 28.3 weeks, P=0.033) and length of the stay in hospital (89.5 days vs 75.4 days, P=0.042). The screening tool with the most positive results was CSBS-DP-ITC (42 positive screens [PS]), followed by M-CHAT (28 PS), and ITSP (22 PS). Differences in the frequency of PS among the tests were significant (P=0.008). CSBS-DP-ITC had the highest sensitivity (0.846), followed by M-CHAT (0.692) and ITSP (0.462). CONCLUSION: Our results indicate a higher prevalence of autism in children with birth weights <1,500 g at 2 years of age compared to the general population prevalence. The ASD diagnosis was associated with shorter gestation times and longer hospital stays. Our findings support the simultaneous use of more than one screening tests in order to increase screening sensitivity.

A place in time: situating Chauvet within the long chronology of symbolic behavioral development.

Since the discovery of the Grotte Chauvet (Ardèche, France) in the mid-1990s, there has been a debate regarding the accuracy of assigning this site to the Aurignacian period. The main argument stems from a perceived lack of agreement between the radiocarbon age of the imagery (>32,000 years BP [before present]) and its stylistic complexity and technical sophistication, which some believe are more typical of the later Upper Paleolithic. In this paper we first review the evidence for symbolic behavior among modern humans during the Aurignacian in order to explore the question of whether Chauvet's images are anachronistic. Then, using a database of non-figurative signs found in Paleolithic parietal art, we undertake a detailed comparison between Chauvet's corpus of signs and those found in other French Upper Paleolithic caves. While we conclude that there is substantial evidence to support an Aurignacian date for Grotte Chauvet, we also suggest that it may be time to revisit some of the cultural boundaries that are currently in use in Paleolithic archaeology.

Thematic Matching as Remedial Teaching for Symbolic Matching for Individuals with Autism Spectrum Disorder.

Matching-to-sample (MTS) is often used to teach symbolic relationships between spoken or printed words and their referents to children with intellectual and developmental disabilities. However, many children have difficulty learning symbolic matching, even though they may demonstrate generalized identity matching. The current study investigated whether training on symbolic MTS tasks in which the stimuli are physically dissimilar but members of familiar categories (i.e., thematic matching) can remediate an individual's difficulty learning symbolic MTS tasks involving non-representative stimuli. Three adolescent males diagnosed with autism spectrum disorder were first trained on symbolic MTS tasks with unfamiliar, non-representative form stimuli. Thematic matching was introduced after the participants failed to learn 0, 2 or 4 symbolic MTS tasks and before additional symbolic MTS tasks were introduced. After exposure to thematic matching, accuracy on symbolic MTS tasks with novel stimuli increased to above chance for all participants. For two participants, high accuracy (> 90%) was achieved on a majority of these sessions. Thus, thematic matching may be an effective intervention for students with limited verbal repertoires and who have difficulty learning symbolic MTS tasks. Possible explanations for the facilitative effect of thematic matching are considered and warrant further investigation.