Biomedical subjects

D Natsopoulos

Publications and source records attributed to D Natsopoulos.

11 recordsLinked to original sources

PubMed2002

Differences in language performance in variations of lateralization.

Language proficiency was studied in 489 primary-school-aged children classified as extreme left-, extreme right-, mild left-, and mild right-handers on the basis of both hand-preference and hand-skill, using a test battery of seven measures. An ANOVA run on factor scores showed neither significant association of language proficiency with variations of lateralization regarding hand-preference and hand-skill nor differences in factor structure derived from a principal component analysis between extreme vs. mild hand-preference and hand-skill groups. Moreover, low language proficiency was not significantly associated with specific patterns of lateralization in hand-preference subgroups. In contrast, low language performers with poor hand-skill were significantly overrepresented both in the extreme left-handed group alone and when combined with the extreme right-handed, in comparison to mild left- and mild right-handed with respect to population. The data are not consistently accommodated by the theory of balanced polymorphism (mainly Annett, 1978, 1985 Annett & Manning, 1989 ). Alternately, factors such as lag of maturation ( Bishop, 1980, 1984, 1990a, 1990b ), delay of growth ( Geschwind & Galaburda, 1985b ), and developmental instability associated with unique patterns of variations in lateralization ( Yeo, Gangestad, & Daniel, 1993 ) are discussed as possible factors accounting for the present results.

Brain↗

PubMed1998

Do the hands talk on mind's behalf? Differences in language ability between left- and right-handed children.

Two hundred seventy children of school age, 135 of whom were left-handed and an equivalent number of whom were right-handed, have been examined in the present study using a test battery of nine language ability measures: Vocabulary, Similarities, Comprehension (WISC-R), Deductive Reasoning, Inductive Reasoning, Sentence Completion, Comprehension of Sentential Semantics, Comprehension of Syntax, and Text Processing. The data analysis has indicated that: (1) One-factor solution applies both to the right- and left-handed population according to Standard Error Scree Method (Zoski & Jurs, 1996) with regard to language ability measures. (2) Handedness discriminates between right-handers (superior) and left-handers (inferior) in language ability. (3) There have been subgroups of left-handed children who differ in language ability distribution compared with right-handed children according to Hierarchical Cluster Analysis. (4) Extreme versus mild bias to hand preference and hand skill do not differentiate performance subgroups neither within the left-handed nor within the right-handed main group. (5) Sex and familial sinistrality do not affect performance. The results are discussed in relation to (a) "human balanced polymorphism" theory advocated by Annett (mainly Annett, 1985, 1993a; Annett & Manning, 1989), (b) potential pathology (mainly Bishop, 1984, 1990a; Coren & Halpern, 1991; Satz, Orsini, Saslow & Henry, 1985) and "developmental instability" (Yeo, Gangestad & Daniel, 1993), and delay of left-hemisphere maturation in left-handed individuals (Geschwind & Galaburda, 1985a,b, 1987), by pointing out the strength and weaknesses of these theoretical approaches in accounting for the present data.

Brain↗

PubMed1998

On the concept of comparison in mentally retarded and nonretarded children.

Two adjective pairs in comparative form, more-less and taller-shorter, were tested with moderately mentally retarded (MR) and nonretarded children (NR) matched on verbal mental age (MA) and socioeconomic status (SES) in a "show" and an "act-out" experimental condition. The data indicated that all the main effects, the group, the experimental condition, and the unmarked-marked relational terms were significant and so were the interactions of the Group x Experimental Conditions, Group x Unmarked Versus Marked Relational Terms, and Group x Experimental Conditions and Unmarked Versus Marked Relational Terms. A logistic regression analysis (LRA) showed that the relational term shorter in the act-out condition best predicted classification membership for the subjects in either group, suggesting that the MR children were less able to self-regulate behavior. The error types, however, mainly observed in the act-out experimental condition were the same from a semantic point of view in either group. The effect of the unmarked versus marked distinction cannot be considered independent of the experimental conditions applied.

Child↗

PubMed1997

Deductive and inductive reasoning in Parkinson's disease patients and normal controls: review and experimental evidence.

In the present study, fifty-four subjects were tested; twenty-seven with idiopathic Parkinson's disease and twenty-seven normal controls matched in age, education, verbal ability, level of depression, sex and socio-economic status. The subjects were tested on eight tasks. Five of the tasks were the classic deductive reasoning syllogisms, modus ponens, modus tollendo tollens, affirming the consequent, denying the antecedent and three-term series problems phrased in a factual context (brief scripts). Three of the tasks were inductive reasoning, including logical inferences, metaphors and similes. All tasks were presented to subjects in a multiple choice format. The results, overall, have shown nonsignificant differences between the two groups in deductive and inductive reasoning, an ability traditionally associated with frontal lobes involvement. Of the comparisons performed between subgroups of the patients and normal controls concerning disease duration, disease onset and predominant involvement of the left and/or right hemisphere, significant differences were found between patients with earlier disease onset and normal controls and between bilaterally affected patients and normal controls, demonstrating an additive effect of lateralization to reasoning ability.

Adult↗

PubMed1993

Algorithmic and heuristic strategies in comprehension of complement clauses by patients with Parkinson's disease.

Language ability in patients with idiopathic Parkinson's disease (PD) and normal control subjects (NC) matched on age, sex, education and socioeconomic status (SES) was investigated. The two groups of subjects were tested on eight sentence types in Greek in the form of main and complement clause with eight matrix verbs. These matrix verbs were ask (ask information), promise (commissive meaning), tell1 (order, command) and tell2 (give information) in sentences with no semantic constraints, and confess, sell, trust and scold in sentences with semantic constraints (implicit causality). The results show that language ability, despite relative preservation is significantly impaired in PD patients as compared to that of NC. More specifically, syntax with semantic constraints was the most effective independent variable to classify PD patients and NC subjects into two distinct groups according to a Logistic Regression Analysis. To restrict the algorithmic process in sentence comprehension, PD patients seem to make use of the minimal distance principle (MDP) and the "experiencer constraint" heuristic strategies. Possible similarities in language behavior between PD patients and aphasics, in general, are suggested.

Aged↗

PubMed1992

Handedness and spatial ability in children: further support for Geschwind's hypothesis of "pathology of superiority" and for Annett's theory of intelligence.

Spatial ability of 60 left-handed and 60 right-handed school children was investigated using a battery of nine tasks. The results do not agree with Levy's (1969, 1976) theory predicting spatial inferiority of left-handed individuals. Instead, higher performance by left-handed children provided further support for Annett's (Annett & Manning, 1989) theory on intelligence and for Geschwind's (Geschwind & Galaburda, 1985) hypothesis of "pathology of superiority." The distinction of left-handed and right-handed individuals into familial and nonfamilial groups appeared to be psychologically equivocal according to our results.

Aptitude↗

PubMed1991

Understanding of relational time terms before and after in Parkinsonian patients.

The role of the relational time terms before and after in language comprehension was investigated using patients with Parkinson's disease (PD) and normal controls (NC) in Greek. Results lead to the following four conclusions: (a) Comprehension by PD patients of before and after constructions displaying syntactic, semantic, and cognitive constraints equivalent to those of English is significantly different from that of NC matched on chronological age, sex, education, and socioeconomic status. (b) Before is better understood than after. (c) Syntactic variables, when semantic effects are partialed out, do not affect performance. The same is true of semantic effects when syntactic variables are partialed out. (d) Order of mention of events is a predominant source of errors when syntax and semantics are controlled. The data are discussed in relation both to findings with aphasics and to developmental results on the same time terms.

Aged↗

PubMed1991

Strategies in comprehension of relative clauses by parkinsonian patients.

Twenty patients with Parkinson disease (PD) and twenty normal control subjects (NC) matched on age, sex, education and socio-economic status (SES) were tested for comprehension of four types of relative clauses with complex thematic roles (syntax) and no semantic and pragmatic constraints (reversible) in a sentence-picture matching task. The results show a clear language impairment for PD patients compared to NC. Additional evidence from testing school children in grade 1 (G1) and grade 6 (G6) indicates that G1 children perform similar to PD patients and G6 children perform as high as NC. The overall picture of the findings suggests: (1) PD patients process sentences with complex thematic roles and semantic reversibility on a heuristic and not on an algorithmic basis, a type of behavior assumed to be associated with frontal lobe dysfunction; (2) PD patients display some patterns of language behavior similar to those observed in aphasics. Similarities in language behavior between PD patients and G1 children are discussed with regard to the "regression hypothesis" (Jacobson, 1968).

Aged↗

PubMed1991

Preschoolers' construction order of event sequences related to mental ability and degree of familiarity.

Preschoolers' understanding of sequential relations was investigated in two experiments. Experiment 1 showed that appreciation of sequential relations depends on the level of mental ability and the degree of familiarity displayed with the social or behavioral phenomena under investigation. Experiment 2 reproduced the findings of Experiment 1 and, further, demonstrated that an increase in experience and familiarity through an interaction phase between children with higher and those with lower mental abilities led to a significant exchange of information and performance that was retained over the posttest phase. The data of both experiments are discussed within the framework of the "invariance hypothesis" (Bullock, 1985) in contrast to Piagetian theory (Piaget, 1946/1969).

Aptitude↗

PubMed1990

Language behavior by mildly handicapped and nonretarded children on complement clauses.

Comprehension of complement clauses embedded into four matrix verbs in Greek, equivalent to English in syntactic and semantic constraints, was investigated with mildly handicapped (MH) and nonretarded children (NR). The results suggest that: (a) the MH children use the same syntactic information in comprehension of complement clauses as the NR children, (b) verbal MA cannot best predict linguistic performance by MH and NR children. (c) Digit Span does not correlate with comprehension nor does verbal IQ in MH., (d) Digit Span and verbal IQ are significantly correlated with NR children's comprehension, (e) the psychological status of the minimal distance principle (MDP) is debatable, while the semantic role principle (SRP) is partially supported by the data, (f) MH children lack metalinguistic ability compared to young NR children.

Adolescent↗

PubMed1989

Children's and adults' perception of missing subjects in complement clauses: evidence from another language.

Findings on perception of missing subjects in complement clauses are reported in two experiments with school-aged children and adults. The complement clauses were embedded into four matrix verbs in Greek, such as Ask (ask information), Promise, Tell (order/command), and Tell (give information) equivalent to English in syntactic and semantic constraints. The data from Experiment 1 show the following: (1) Perception of missing subjects in Ask, Promise, and Tell complement clauses is significantly higher than in Tell, but Guttman coefficient of scalability (.58) was slightly lower than the required one (over .60) to document a developmental sequence between the four constructions. (2) In general, these results, as other findings, contradict with Minimal Distance Principle (MDP) advocated by Chomsky (1969, 1972). (3) Differences in perceiving the source (i.e., NP) in Ask and Promise and the goal/recipient (i.e., NP) as subject in the complement clauses on Tell and Tell cannot consistently be explained by the Semantic Role Principle (SRP) postulated by Maratsos (Lederberg & Maratsos, 1981; Maratsos, 1974) either. (4) Results from Experiment 2 with three age groups, despite minor differences, confirm the results in Experiment 1, suggesting that comprehension of complement clauses with Ask, Promise, and Tell is a prerequisite to comprehension of complement clauses with Tell, according to Guttman coefficients of scalability (over .60 for all groups). (5) The findings are discussed within the framework of the SRP, but the emphasis is placed on the interaction of semantic and pragmatic presuppositions over processing the four construction types.

Adolescent↗