Activity of neurons in human temporal cortex during identification and memory for names and words. (1/196)

Extracellular recordings of human temporal cortical neuronal activity during identification and memory for object names or words were obtained from 31 neurons at 18 sites in 12 left language dominant patients undergoing left (10) or right (2) awake craniotomy for epilepsy under local anesthesia. Frequency of activity during identification was compared with perceptual controls, that during the encoding phase of recent memory to identification of the same material. Statistically significant changes in one or more temporal epoch (p < 0.005) of one or more comparisons were present for 27 of the 31 neurons in either hemisphere. Few neurons changed activity in the same direction for both words and names. The instruction to retain an item in recent memory changed activity in most neurons from that during identification of the same material, although the items presented were identical and overtly identified in each task. Any individual neuron usually changed activity in one direction for only one task. There are separate, widely distributed neural networks for identification or recent memory for each type of material. The majority of nearby neurons recorded through the same extracellular microelectrode were related to the networks for different tasks. The temporal characteristics of these changes were also investigated; 31% of the changes were "phasic": temporally related to presentation or response to the item. Most of the remaining neuron changes were sustained throughout a task, often for several minutes. These task-specific sustained changes may reflect effects of thalamo-cortical attentional systems. Individual neurons had both sustained and phasic changes to different tasks.  (+info)

Difficulties with anonymous shortlisting of medical school applications and its effects on candidates with non-European names: prospective cohort study. (2/196)

OBJECTIVE: To assess the feasibility of anonymous shortlisting of applications for medical school and its effect on those with non-European names. DESIGN: Prospective cohort study. SETTING: Leeds school of medicine, United Kingdom. SUBJECTS: 2047 applications for 1998 entry from the United Kingdom and the European Union. INTERVENTION: Deletion of all references to name and nationality from the application form. MAIN OUTCOME MEASURES: Scoring by two admissions tutors at shortlisting. RESULTS: Deleting names was cumbersome as some were repeated up to 15 times. Anonymising application forms was ineffective as one admissions tutor was able to identify nearly 50% of candidates classed as being from an ethnic minority group. Although scores were lower for applicants with non-European names, anonymity did not improve scores. Applicants with non-European names who were identified as such by tutors were significantly less likely to drop marks in one particular non-academic area (the career insight component) than their European counterparts. CONCLUSIONS: There was no evidence of benefit to candidates with non-European names of attempting to blind assessment. Anonymising application forms cannot be recommended.  (+info)

Visual confrontation naming and hippocampal function: A neural network study using quantitative (1)H magnetic resonance spectroscopy. (3/196)

Prior research on the relationship between visual confrontation naming and hippocampal function has been inconclusive. The present study examined this relationship using quantitative (1)H magnetic resonance spectroscopy ((1)H-MRS) to operationalize the function of the left and right hippocampi. The 60-item Boston Naming Test (BNT) was used to measure naming. Our sample included 46 patients with medically intractable, focal mesial temporal lobe epilepsy who had been screened for all pathology other than mesial temporal sclerosis. Statistics included Pearson correlations and neural network analysis (multilayer perceptron and radial basis function). Baseline BNT performance correlated significantly with left (1)H-MRS hippocampal ratios. Thirty-six per cent of the variance in baseline BNT performance was explained by a neural network model using left and right (1)H-MRS ratios(creatine/N-acetylaspartate) as input. This was elevated to 49% when input from the right hippocampus was lesioned mathematically. In a second model, left (1)H-MRS hippocampal ratios were modelled using measures of semantic and episodic memory as input (including the BNT). Explained variance in left (1)H-MRS hippocampal ratios fell from 60.8 to 3.6% when input from BNT and another semantic memory measure was degraded mathematically. These results provide evidence that the speech-dominant hippocampus is a significant component of the overall neuroanatomical network of visual confrontation naming. Clinical and theoretical implications are explored.  (+info)

Surnames and the Y chromosome. (4/196)

A randomly ascertained sample of males with the surname "Sykes" was typed with four Y-chromosome microsatellites. Almost half the sample shared the same Y-chromosome haplotype, which has not been observed in control samples either from the same geographic region or from the United Kingdom as a whole. This points to a single surname founder for extant Sykes males, even though written sources had predicted multiple origins. The distribution of other Sykes Y-chromosome haplotypes were not significantly different from those in controls and may be accounted for by the historical accumulation of nonpaternity during the past 700 years, in which case the average rate estimate is 1.3%/generation. If this pattern is reproduced with other surnames, it may have important forensic and genealogical applications.  (+info)

Correlation between molecular and conventional genealogies in Aicuna: a rural population from Northwestern Argentina. (5/196)

Aicuna is a village in the northwest of Argentina, located about 300 km south of La Rioja city, in the province of La Rioja. The population of Aicuna derives from a founder couple established in the uninhabited Aicuna valley in the early years of the 17th century. Due to land ownership litigation, the descendants maintained a well-documented genealogy that extends for 12 generations, comprising more than 8,000 individuals. From the historical pedigree of Aicuna, we selected 14 males with direct patrilineal descent from the 2 most ancient male founders, and 23 donors (9 females and 14 males) with direct matrilineal descent from the most ancient female founder. All 3 founders lived in the 17th century. We collected DNA from buccal swabs and characterized the mitochondrial DNA (mtDNA) and Y haplotypes using 14 Y-specific markers, 11 mtDNA polymorphic markers and sequencing of the mt hypervariable regions 1 and 2. We found four different Y haplotypes: Y1 and Y2 haplotypes of European origin corresponding to the founder ancestors Francisco Paez de Espinoza and Apolinario Ormeno, which were shared by 6 and 3 donors, respectively. Three males selected as Ormeno patrilineal descendants showed a different Y haplotype (Y3), probably originated by erroneous paternity registration due to illegitimacy. The remaining case (haplotype Y4), also assumed to belong to the Ormeno lineage, was probably also due to an erroneously registered paternity. Twenty-two donors showed an association of mtDNA markers corresponding to the Amerindian haplotype A2. The founder of this matrilineage could be traced back for more than 14 generations. The haplotype B of one remaining female did not correspond with the historical pedigree and could be due to an error in the genealogy registration. Our results showed an 85% agreement between conventional and molecular genealogies, with mtDNA markers being Amerindian, and Y markers being European. The methodology used in this report is a tool which could potentially be employed as a precedent for land ownership by Aicuna villagers and Amerindian populations.  (+info)

An assessment of the Nam Pehchan computer program for the identification of names of south Asian ethnic origin. (6/196)

BACKGROUND: An assessment was made of the usefulness and accuracy of a computer program for the identification of the south Asian population through the classification of names on a disease register. METHODS: The computer program, Nam Pehchan, was used to classify names as either south Asian or non south Asian. The results were compared with a reference standard, which combined use of the program with visual inspection. The latter was facilitated by a computer-generated dictionary of common non south Asian names. The data set consisted of 356,555 cases of incident cancer (ICD9: 140-208) registered between 1990 and 1992 by Thames, Trent, West Midlands and Yorkshire cancer registries. RESULTS: Nam Pehchan classified 5506 cases as south Asian. Visual inspection identified 2024 false positives (36.8 per cent of all cases identified as south Asian by Nam Pehchan) and 363 false negatives (9.5 per cent of those identified by the reference standard). Compared with the reference standard, Nam Pehchan had a sensitivity of 90.5 per cent and a positive predictive value of 63.2 per cent. CONCLUSION: The Nam Pehchan program quickly identified a high proportion of the names classified as south Asian by the reference standard, but the high false positive rate means that the program alone is not an adequate single strategy. The time-consuming process of inspection of program negatives for large data sets can be substantially reduced by comparison with dictionaries of common non south Asian names.  (+info)

Appendicectomies in Albanians in Greece: outcomes in a highly mobile immigrant patient population. (7/196)

BACKGROUND: Albanian immigrants in Greece comprise a highly mobile population with unknown health care profile. We aimed to assess whether these immigrants were more or less likely to undergo laparotomy for suspected appendicitis with negative findings (negative appendicectomy), by performing a controlled study with individual (1:4) matching. We used data from 6 hospitals in the Greek prefecture of Epirus that is bordering Albania. RESULTS: Among a total of 2027 non-incidental appendicectomies for suspected appendicitis performed in 1994-1999, 30 patients with Albanian names were matched (for age, sex, time of operation and hospital) to 120 patients with Greek names. The odds for a negative appendicectomy were 3.4-fold higher (95% confidence interval [CI], 1.24-9.31, p = 0.02) in Albanian immigrants than in matched Greek-name subjects. The difference was most prominent in men (odds ratio 20.0, 95% CI, 1.41-285, p = 0.02) while it was not formally significant in women (odds ratio 1.56, 95% CI, 0.44-5.48). The odds for perforation were 1.25-fold higher in Albanian-name immigrants than in Greek-name patients (95% CI 0.44- 3.57). CONCLUSIONS: Albanian immigrants in Greece are at high risk for negative appendicectomies. Socioeconomic, cultural and language parameters underlying health care inequalities in highly mobile immigrant populations need better study.  (+info)

Nominal kinship cues facilitate altruism. (8/196)

We investigated whether names in common promote altruistic behaviour, predicting that this would be especially so for relatively uncommon names, for surnames (which are better kinship cues than first names), and among women (who, although less willing than men to help strangers, according to prior research, are also the primary "kin keepers"). We solicited help from 2960 email addressees, with the request ostensibly coming from a same-sex person sharing both, either, or neither of the addressee's first and last names. As anticipated, addressees were most likely to respond helpfully when senders shared both their names (12.3%) and least likely when they shared neither (2.0%), and this was especially true for relatively uncommon names. A shared surname was more effective than a shared first name only if it was relatively uncommon. Women were substantially more likely to reply than men. These results indicate that names elicit altruism because they function as salient cues of kinship.  (+info)