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1.
Proc Biol Sci ; 283(1825): 20152402, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26911964

RESUMEN

The variety and complexity of human-made tools are unique in the animal kingdom. Research investigating why human tool use is special has focused on the role of social learning: while non-human great apes acquire tool-use behaviours mostly by individual (re-)inventions, modern humans use imitation and teaching to accumulate innovations over time. However, little is known about tool-use behaviours that humans can invent individually, i.e. without cultural knowledge. We presented 2- to 3.5-year-old children with 12 problem-solving tasks based on tool-use behaviours shown by great apes. Spontaneous tool use was observed in 11 tasks. Additionally, tasks which occurred more frequently in wild great apes were also solved more frequently by human children. Our results demonstrate great similarity in the spontaneous tool-use abilities of human children and great apes, indicating that the physical cognition underlying tool use shows large overlaps across the great ape species. This suggests that humans are neither born with special physical cognition skills, nor that these skills have degraded due to our species' long reliance of social learning in the tool-use domain.


Asunto(s)
Cognición , Pan troglodytes/fisiología , Pongo/fisiología , Solución de Problemas , Comportamiento del Uso de la Herramienta , Animales , Preescolar , Femenino , Alemania , Humanos , Aprendizaje , Masculino , Juego e Implementos de Juego , Reino Unido
2.
Evol Hum Sci ; 4: e5, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37588934

RESUMEN

Associative Tool Use (ATU) describes the use of two or more tools in combination, with the literature further differentiating between Tool set use, Tool composite use, Sequential tool use and Secondary tool use. Research investigating the cognitive processes underlying ATU has shown that some primate and bird species spontaneously invent Tool set and Sequential tool use. Yet studies with humans are sparse. Whether children are also able to spontaneously invent ATU behaviours and at what age this ability emerges is poorly understood. We addressed this gap in the literature with two experiments involving preschoolers (E1, N = 66, 3 years 6 months to 4 years 9 months; E2, N = 119, 3 years 0 months to 6 years 10 months) who were administered novel tasks measuring Tool set, Metatool and Sequential tool use. Participants needed to solve the tasks individually, without the opportunity for social learning (except for enhancement effects). Children from 3 years of age spontaneously invented all of the types of investigated ATU behaviours. Success rates were low, suggesting that individual invention of ATU in novel tasks is still challenging for preschoolers. We discuss how future studies can use and expand our tasks to deepen our understanding of tool use and problem-solving in humans and non-human animals.

3.
Eur Addict Res ; 17(3): 164-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21447953

RESUMEN

Acute alcohol consumption is associated with socially inappropriate behaviour. Such behaviour could in part reflect the potential of alcohol to interfere with social cognition. In this experiment we tested the hypothesis that acute alcohol consumption by regular heavy social drinking young adults would compromise an aspect of social cognition, namely theory of mind (understanding intentions, emotions and beliefs). Participants who had consumed 6-8 units of alcohol showed specific impairments on two theory of mind tests: identification of faux pas and emotion recognition. This result suggests that alcohol consumption could lead to social problems secondary to difficulties in interpreting the behaviour of others due to theory of mind impairments.


Asunto(s)
Intoxicación Alcohólica/psicología , Emociones/fisiología , Conducta Social , Percepción Social , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/psicología , Intoxicación Alcohólica/complicaciones , Emociones/efectos de los fármacos , Etanol/administración & dosificación , Femenino , Humanos , Masculino , Teoría de la Mente/efectos de los fármacos , Teoría de la Mente/fisiología , Adulto Joven
4.
Sci Rep ; 7(1): 1788, 2017 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-28496154

RESUMEN

The ratchet effect - the accumulation of beneficial changes in cultural products beyond a level that individuals could reach on their own - is a topic of increasing interest. It is currently debated which social learning mechanisms allow for the generation and transmission of cumulative culture. This study focused on transmission, investigating whether 4- to 6-year-old children were able to copy cumulative technological design and whether they could do so without action information (emulation). We adapted the spaghetti tower task, previously used to test for accumulation of culture in human adults. A baseline condition established that the demonstrated tower design was beyond the innovation skills of individual children this age and so represented a culture-dependent product for them. There were 2 demonstration conditions: a full demonstration (actions plus (end-)results) and an endstate- demonstration (end-results only). Children in both demonstration conditions built taller towers than those in the baseline. Crucially, in both demonstration conditions some children also copied the demonstrated tower. We provide the first evidence that young children learn from, and that some of them even copy, cumulative technological design, and that - in line with some adult studies - action information is not always necessary to transmit culture-dependent traits.


Asunto(s)
Cultura , Conducta Imitativa , Conducta Social , Factores de Edad , Niño , Preescolar , Creatividad , Femenino , Humanos , Masculino , Tecnología
5.
J Med Genet ; 42(9): 720-4, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16141008

RESUMEN

BACKGROUND: Dyslipidaemia is a well known risk factor for cardiovascular disease (CVD). Lipid metabolism is affected by a range of genes and proteins. This study investigated whether some of these genes are associated with measures of subclinical CVD. METHODS: Polymorphisms of paraoxonase 1 and 2, cholesteryl ester transfer protein, hepatic lipase, and lipoprotein lipase were tested for associations with measures of subclinical CVD including carotid intima-media thickness measured by B-mode ultrasound and carotid and coronary arterial calcification measured by computed tomography. Analysis was performed in 620 European American participants in the Diabetes Heart Study, 83% of whom had type 2 diabetes mellitus. Associations of genotypes with subclinical CVD were tested by computing a series of generalised estimating equations. RESULTS: The Q192R variant of paraoxonase 1 and rs285 of lipoprotein lipase were associated with carotid artery calcium (p values = 0.002 and 0.005, respectively). Paraoxonase 2 S311C was associated with coronary artery calcium (p value = 0.037). CONCLUSIONS: There is evidence for modest, but significant, association of multiple single nucleotide polymorphisms in lipid genes with measures of subclinical CVD.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Diabetes Mellitus Tipo 2/sangre , Metabolismo de los Lípidos , Anciano , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , ADN/sangre , ADN/genética , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Metabolismo de los Lípidos/genética , Masculino , Persona de Mediana Edad
6.
Health Technol Assess ; 9(8): 1-192, iii-iv, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15763039

RESUMEN

OBJECTIVES: To research the lay public's understanding of equipoise and randomisation in randomised controlled trials (RCTs) and to look at why information on this may not be not taken in or remembered, as well as the effects of providing information designed to overcome barriers. DESIGN: Investigations were informed by an update of systematic review on patients' understanding of consent information in clinical trials, and by relevant theory and evidence from experimental psychology. Nine investigations were conducted with nine participants. SETTING: Access (return to education), leisure and vocational courses at Further Education Colleges in the Midlands, UK. PARTICIPANTS: Healthy adults with a wide range of educational backgrounds and ages. INVESTIGATIONS: Participants read hypothetical scenarios and wrote brief answers to subsequent questions. Sub-samples of participants were interviewed individually to elaborate on their written answers. Participants' background assumptions concerning equipoise and randomisation were examined and ways of helping participants recognise the scientific benefits of randomisation were explored. MAIN OUTCOME MEASURES: Judgments on allocation methods; treatment preferences; the acceptability of random allocation; whether or not individual doctors could be completely unsure about the best treatment; whether or not doctors should reveal treatment preferences under conditions of collective equipoise; and how sure experts would be about the best treatment following random allocation vs doctor/patient choice. Assessments of understanding hypothetical trial information. RESULTS: Recent literature continues to report trial participants' failure to understand or remember information about randomisation and equipoise, despite the provision of clear and readable trial information leaflets. In current best practice, written trial information describes what will happen without offering accessible explanations. As a consequence, patients may create their own incorrect interpretations and consent or refusal may be inadequately informed. In six investigations, most participants identified which methods of allocation were random, but judged the random allocation methods to be unacceptable in a trial context; the mere description of a treatment as new was insufficient to engender a preference for it over a standard treatment; around half of the participants denied that a doctor could be completely unsure about the best treatment. A majority of participants judged it unacceptable for a doctor to suggest letting chance decide when uncertain of the best treatment, and, in the absence of a justification for random allocation, participants did not recognise scientific benefits of random allocation over normal treatment allocation methods. The pattern of results across three intervention studies suggests that merely supplementing written trial information with an explanation is unlikely to be helpful. However, when people manage to focus on the trial's aim of increasing knowledge (as opposed to making treatment decisions about individuals), and process an explanation actively, they may be helped to understand the scientific reasons for random allocation. CONCLUSIONS: This research was not carried out in real healthcare settings. However, participants who could correctly identify random allocation methods, yet judged random allocation unacceptable, doubted the possibility of individual equipoise and saw no scientific benefits of random allocation over doctor/patient choice, are unlikely to draw upon contrasting views if invited to enter a real clinical trial. This suggests that many potential trial participants may have difficulty understanding and remembering trial information that conforms to current best practice in its descriptions of randomisation and equipoise. Given the extent of the disparity between the assumptions underlying trial design and the assumptions held by the lay public, the solution is unlikely to be simple. Nevertheless, the results suggest that including an accessible explanation of the scientific benefits of randomisation may be beneficial provided potential participants are also enabled to reflect on the trial's aim of advancing knowledge, and to think actively about the information presented. Further areas for consideration include: the identification of effective combinations of written and oral information; helping participants to reflect on the aim of advancing knowledge; and an evidence-based approach to leaflet construction.


Asunto(s)
Comprensión , Consentimiento Informado , Juicio , Ensayos Clínicos Controlados Aleatorios como Asunto/ética , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comunicación , Femenino , Humanos , Consentimiento Informado/ética , Consentimiento Informado/psicología , Masculino , Memoria , Persona de Mediana Edad , Selección de Paciente/ética , Ensayos Clínicos Controlados Aleatorios como Asunto/psicología , Proyectos de Investigación , Sujetos de Investigación/psicología , Revelación de la Verdad/ética
7.
Am J Ophthalmol ; 106(6): 696-702, 1988 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-3057917

RESUMEN

Variability of optic disk topographic measurements obtained with the Rodenstock Optic Nerve Head Analyzer was determined by obtaining three separate images on one eye of ten normal subjects and nine subjects without glaucoma. Marking of the disk margin was performed in a random and masked fashion on each image three times by three independent observers. The overall variabilities of the measurements of the subjects with glaucoma were not statistically different from those of the normal subjects. Overall variability was about 0.2 mm2 for total disk area, 0.08 for cup/disk ratio, 0.2 mm2 for disk rim area, and 0.07 mm3 for cup volume. The largest component of the variability was the result of acquisition of separate images of the optic disk at different times. Observer inconsistency in marking the disk edge was relatively small. Based on the expected amount of random variability of the measurements, we proposed criteria for detecting significant change in the optic disk over time.


Asunto(s)
Diagnóstico por Computador/instrumentación , Oftalmología/instrumentación , Disco Óptico/patología , Adulto , Anciano , Análisis de Varianza , Diagnóstico por Computador/normas , Estudios de Evaluación como Asunto , Femenino , Glaucoma/patología , Humanos , Masculino , Persona de Mediana Edad , Oftalmología/normas , Valores de Referencia
8.
AAPS PharmSciTech ; 1(2): E11, 2000 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-14727844

RESUMEN

A high performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed to measure the thymosin alpha 1 (Talpha1) concentration in human serum. Tá1 in human serum was determined by solid phase extraction and reverse phase LC-MS/MS. The high-performance liquid chromatography (HPLC) system interfaced with the MS/MS system with a Turbo Ion spray interface. Positive ion detection and multiple reaction monitoring (MRM) mode were used for this human serum quantitation. Eight different concentration standards were used to establish the detection range. Six quality control (QC) and 2 matrix blanks were checked by calibration curves performed on the same day. The lower quantitation limit was 0.5 ng/mL Talpha1 in human serum. Calibration curves were established between 0.5 to 100 ng/mL by weighted linear regression. The correlation coefficients for different days were 0.9955 or greater. Quantitation of Talpha1 by the LC-MS/MS method is fast, accurate, and precise.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Timosina/análogos & derivados , Timosina/sangre , Calibración , Humanos , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Timalfasina
9.
Biotechnol Prog ; 1(2): 147-50, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20568152
10.
Br J Psychol ; 100(Pt 4): 645-59, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19079952

RESUMEN

An established finding is that adults prefer to guess before rather than after a chance event has happened. This is interpreted in terms of aversion to guessing when relatively incompetent: After throwing, the fall could be known. Adults (N=71, mean age 18;11, N=28, mean age 48;0) showed this preference with imagined die-throwing as in the published studies. With live die-throwing, children (N=64, aged 6 and 8 years; N=50, aged 5 and 6 years) and 15-year-olds (N=93, 46) showed the opposite preference, as did 17 adults. Seventeen-year-olds (N=82) were more likely to prefer to guess after throwing with live rather than imagined die-throwing. Reliance on imagined situations in the literature on decision-making under uncertainty ignores the possibility that adults imagine inaccurately how they would really feel: After a real die has been thrown, adults, like children, may feel there is less ambiguity about the outcome.


Asunto(s)
Conducta de Elección , Toma de Decisiones , Juego de Azar/psicología , Imaginación , Aprendizaje por Probabilidad , Incertidumbre , Adolescente , Adulto , Niño , Preescolar , Cultura , Miedo , Femenino , Humanos , Juicio , Masculino , Autoeficacia , Percepción Social , Adulto Joven
11.
Int J Obes (Lond) ; 29(1): 67-77, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15534617

RESUMEN

OBJECTIVE: To conduct linkage analysis for body mass index (BMI, kg/m2), waist-to-hip ratio (WHR), visceral adipose tissue mass (VAT, cm2) and subcutaneous adipose tissue mass (SAT, cm2) using a whole genome scan. DESIGN: Cross-sectional family study. STUDY SUBJECTS: African-American families from Los Angeles (AA, n=21 extended pedigrees) and Hispanic-American families (HA) from San Antonio, TX (HA-SA, n=33 extended pedigrees) and San Luis Valley, CO (HA-SLV, n=12 extended pedigrees), totaling 1049 individuals in the Insulin Resistance and Atherosclerosis (IRAS) Family Study. MEASUREMENTS: VAT and SAT were measured using a computed tomography scan obtained at the fourth and fifth lumbar vertebrae. All phenotypes were adjusted for age, gender, and study center. VAT, SAT, and WHR were analyzed both unadjusted and adjusted for BMI. RESULTS: Significant linkage to BMI was found at D3S2387 (LOD=3.67) in African-Americans, and at D17S1290 in Hispanic-Americans (LOD=2.76). BMI-adjusted WHR was linked to 12q13-21 (D12S297 (LOD=2.67) and D12S1052 (LOD=2.60)) in Hispanic-Americans. The peak LOD score for BMI-adjusted VAT was found at D11S2006 (2.36) in Hispanic families from San Antonio. BMI-adjusted SAT was linked to D5S820 in Hispanic families (LOD=2.64). Evidence supporting linkage of WHR at D11S2006, VAT at D17S1290, and SAT at D1S1609, D3S2387, and D6S1056 was dependent on BMI, such that the LOD scores became nonsignificant after adjustment of these phenotypes for BMI. CONCLUSIONS: Our findings both replicate previous linkage regions and suggest novel regions in the genome that may harbor quantitative trait locis contributing to variation in measures of adiposity.


Asunto(s)
Índice de Masa Corporal , Obesidad/genética , Carácter Cuantitativo Heredable , Tejido Adiposo/diagnóstico por imagen , Adulto , Negro o Afroamericano , Estudios Transversales , Femenino , Ligamiento Genético , Genotipo , Hispánicos o Latinos , Humanos , Masculino , Obesidad/diagnóstico por imagen , Fenotipo , Tomografía Computarizada por Rayos X , Relación Cintura-Cadera
12.
Diabetologia ; 48(4): 661-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15747111

RESUMEN

AIMS/HYPOTHESIS: The heritability of fasting serum insulin and glucose concentrations in non-diabetic members of multiplex hypertensive families is unknown. METHODS: We calculated the familial aggregation of fasting serum glucose and insulin concentrations and performed a genome-wide scan to assess whether quantitative trait loci contribute to these phenotypes in 2,412 non-diabetic individuals from 1,030 families enrolled in the Hypertension Genetic Epidemiology Network (HyperGEN) in the Family Blood Pressure Program. RESULTS: The heritability (+/-SE) of fasting serum insulin was 0.47+/-0.085 in European Americans and 0.28+/-0.08 in African Americans (p<0.0001 for both), after adjusting for age, sex, and BMI. A genome-wide scan for fasting serum insulin yielded a maximum log of the odds (LOD) score of 2.36 on chromosome 5 at 20 cM (p=0.0004) in European Americans, and an LOD score of 2.28 on chromosome 19 at 11 cM (p=0.0004) in African Americans. The heritability of fasting serum glucose was 0.5109+/-0.08 in the former and 0.29+/-0.09 in the latter (p<0.0003 for both) after adjusting for age, sex and BMI. A genome-wide scan for fasting serum glucose revealed a maximum LOD score of 2.07 on chromosome 5 at 26 cM (p=0.0009) in European Americans. CONCLUSIONS/INTERPRETATION: These analyses demonstrate the marked heritability of fasting serum insulin and glucose concentrations in families enriched for the presence of members with hypertension. They suggest that genes associated with fasting serum insulin concentration are present on chromosomes 19 and 5, and that genes associated with fasting serum glucose concentration are on chromosome 5, in families enriched for hypertension.


Asunto(s)
Glucemia/metabolismo , Genoma Humano , Hipertensión/genética , Insulina/sangre , Sitios de Carácter Cuantitativo/genética , Adulto , Negro o Afroamericano/genética , Anciano , Análisis de Varianza , Cromosomas Humanos Par 19/genética , Cromosomas Humanos Par 5/genética , Salud de la Familia , Ayuno , Femenino , Ligamiento Genético/genética , Genotipo , Humanos , Hipertensión/sangre , Resistencia a la Insulina/genética , Masculino , Cadenas de Markov , Persona de Mediana Edad , Linaje , Fenotipo , Carácter Cuantitativo Heredable , Estados Unidos , Población Blanca/genética
13.
J Exp Child Psychol ; 79(1): 95-114, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11292313

RESUMEN

Consistent with prior research, 5- and 6-year-old children overestimated their knowledge of the intended referent of ambiguous messages. Yet they correctly revised their interpretations of ambiguous messages in light of contradicting information that followed immediately, while maintaining their initial interpretations of unambiguous messages (Experiment 1). Children of this age were able to integrate information over two successive ambiguous messages to identify the intended referent (Experiment 2). However, unlike 7- and 8-year-olds, they were no more likely to search for further information following ambiguous messages compared with unambiguous ones (Experiment 3). We conclude that although 5- and 6-year-olds' interpretations of ambiguous messages are not tentative at the outset, they can use source monitoring skills to treat them as tentative retrospectively, at least over short time spans.


Asunto(s)
Desarrollo Infantil , Cognición , Juicio , Solución de Problemas , Factores de Edad , Niño , Preescolar , Señales (Psicología) , Femenino , Humanos , Masculino
14.
Ophthalmology ; 103(1): 148-51, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8628545

RESUMEN

PURPOSE: The purpose of this article is to examine the occurrence of battered women seen by ophthalmologists in an eye emergency department, and to make ophthalmologists aware that these women are not a rarity but often go unrecognized. METHODS: This retrospective study reviews a large urban eye center's emergency room charts over a 6-month period for documentation of injuries to women as a result of domestic violence. Seventy-nine charts were selected as part of this study. In 18 of these charts, battered women definitely were identified, and in 61 charts abuse was suspected but the abuser was not specifically identified. RESULTS: The patients ranged in age from 15 to 90 years. The abuser was most commonly a boyfriend using a fist as the means of inflicting the injury. Injuries ranged from lacerations and contusions to more serious injuries, including three hyphemas and three ruptured globes. Six patients were hospitalized because of their injuries. Substance abuse was documented in 5 of 79 patients. CONCLUSIONS: Many of these female victims of intentional violence in their homes go unrecognized or uncharted by physicians. Ophthalmologists see many of these women because of the high frequency of head and neck injuries in these cases, and should therefore maintain a high index of suspicion and be prepared to act appropriately with recognition and documentation of the injury and provision of social service referrals.


Asunto(s)
Mujeres Maltratadas , Lesiones Oculares/etiología , Fracturas Orbitales/etiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Violencia Doméstica , Lesiones Oculares/clasificación , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Órbita/lesiones , Estudios Retrospectivos
15.
JAMA ; 274(21): 1672; author reply 1672-3, 1995 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-7474264
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