Predictions of X-linked inheritance for human characteristics

The conclusion reached by H. Thomas and W. Jamison (Developmental Review, 1981, 1, 274–283) that an observed sex-related difference in water-level task performance is due to an X-linked major gene raises the question of whether available data would be consistent with X-linkage predictions other than the one tested. Several predictions of X-linked inheritance for human characteristics are presented and discussed. It was concluded that although water-level task performance may involve a heritable component, the available data from seven independent studies reviewed by Thomas and Jamison are insufficient for determining the specific mode of genetic transmission.     

The redundancy of work alienation and job satisfaction: Some evidence of convergent and discriminant validity

The multitrait-multimethod matrix (MTMM) technique was used in an attempt to help clarify the ambiguities regarding concepts of work alienation, job satisfaction, and the relationships between them. Within each attitude domain considered separately, generally acceptable evidence of convergent and (to a lesser degree) discriminant validity was found for the trait measures (four dimensions of alienation and five of satisfaction). However, the discrimination between alienation and satisfaction measures was no greater than that among satisfaction and among alienation, casting doubt on the demarcation of these as two distinct domains. The measures of satisfaction and alienation also were not correlated differentially with demographic and self-esteem measures. Note was taken of the limitations in our knowledge and operationalization of these areas, as these relate to the assumptions of MTMM technique regarding independence of both underlying trait constructs and measurement methods.     

How big is big? Relative and absolute properties in memory

Previous studies of semantic memory have overlooked an important distinction among so-called “property statements”. Statements with relative adjectives (e.g., Flamingos are big) imply a comparison to a standard or reference point associated with an immediate superordinate category (a flamingo is big for a bird), while the truth of statements with absolute adjectives (e.g., Flamingos are pink) is generally independent of such a standard. To examine the psychological consequences of this distinction, we asked subjects in Experiment 1 to verify sentences containing either relative or absolute adjectives embedded in either predicate-adjective (PA) constructions (e.g., A flamingo is big (pink)) or predicate-noun (PN) constructions (e.g. A flamingo is a big (pink) bird), where the predicate noun was the immediate superordinate. Reaction times (RTs) and errors for relative sentences decreased when the superordinate was specified, but remained constant for absolute sentences. These data also suggest that the truth value of relative sentences depends, not just on the superordinate, but also on a more global standard for everyday, human-oriented objects. Experiment 2 extends these results in showing that ratings of the truth of relative sentences are a function of the difference in size between an instance and its superordinate standard (e.g., between the size of a flamingo and that of an average bird) and the difference between the instance and the standard for everyday objects. Experiment 3 replicated these findings using reaction time as the dependent measure.     

The development of communication: When a bad model makes a good teacher

Five experiments were conducted on what 6-year-old children learn about communication by switching listener and speaker roles with competent and incompetent adults and peers. Experiment I demonstrated that children become better communicators to adults after listening to competent adults, competent peers, and incompetent peers, but not incompetent adults. The age of the listener was shown to have an effect in Experiment II, with children becoming less effective communicators when speaking to a peer after listening to an incompetent peer but better communicators when speaking to an adult after listening to an incompetent peer. Experiments III, IV, and V were designed to determine why children do not improve or deteriorate after listening to incompetent adults. It is not deficient memory: Children remember well the ambiguous messages of adults (Experiment IV). It is not implicit demands to be polite to an adult (Experiment III). It is that children think the ambiguous messages of an adult are competent (Experiment V). Mixing the authority and prestige of an adult with incompetent messages leads the child to ignore the adult's behavior as a standard for his or her own performance. These results suggest that social learning of communication skills might occur best when the child can learn what not to do by interacting with peers and what to do when interacting with adults.     

Social loafing: Allocating effort or taking it easy?

When asked to work both alone and in groups, people exert less effort in groups, a phenomenon we call “social loafing.” Either of two possible strategies could explain this outcome: an allocational strategy where people work as hard as they can overall but conserve their strength for individual trials where work is personally beneficial and a minimizing strategy where the primary motive is to “get by” with the least effort possible. However, an allocational strategy would lead participants who always work in groups to put out as much effort as participants who always work alone, since there is no need to husband strength. Two studies using a sound production task found social loafing even under these conditions, suggesting that allocational strategies are not prevalent. Social loafing seems to occur when people perform together in groups, regardless of whether or not they must also perform alone.     

Learning on a response continuum: Comparison of a linear change and a functional learning model

Two reinforcement schedules were used to compare the predictive validity of a linear change model with a functional learning model. In one schedule, termed “convergent,” the linear change model predicts convergence to the optimum response, while in the other, termed “divergent,” this model predicts that a subject's response will not converge. The functional learning model predicts convergence in both cases. Another factor that was varied was presence or absence of random error or “noise” in the relationship between response and outcome. In the “noiseless” condition, in which no noise is added, a subject could discover the optimum response by chance, so that some subjects could appear to have converged fortuitously. In the “noisy” conditions such chance apparent convergence could not occur.The results did not unequivocally favor either model. While the linear change model's prediction of nonconvergence in the divergent conditions (particularly the “noisy” divergent condition) was not sustained, there was a clear difference in speed of convergence, counter to the prediction inferred from the functional learning model. Evidence that at least some subjects were utilizing a functional learning strategy was adduced from the fact that subjects were able to “map out” the relation between response and outcome quite accurately in a follow-up task. Almost all subjects in the “noisy” conditions had evidently “learned” a strong linear relation, with slope closely matching the veridical one.The data were consistent with a hybrid model assuming a “hierarchy of cognitive strategies” in which more complex strategies (e.g., functional learning) are utilized only when the simpler ones (e.g., a linear change strategy) fail to solve the problem.     

Memory strategies used by young normal and retarded children in a directed forgetting paradigm

Two experiments were reported investigating the possibility that normal children (6- to 7-years old) and retarded children (9- to 10-years old) equated for immediate memory performance may not use effective strategies to eliminate interference from irrelevant information in memory. In both experiments a directed forgetting paradigm was used in which the children were presented with two sets of four pictures, and recalled only one set on each trial. On some trials, there was a cue to forget the first four and to remember only the last four pictures. In the first experiment both groups adopted a passive-active strategy in which the to-be-remembered items were processed actively only after a forget cue. Experiment 2 replicated this pattern of results. The use of sophisticated directed forgetting strategies seemed to be beyond the immediate abilities of these children. Two possible interpretations of the passive-active strategy were offered: (a) The strategy was an attempt to cope with the presence of occasionally irrelevant information and (b) The strategy was an attempt to cope with memory overload.     

Speech timing of grammatical categories

A series of experiments was performed to determine how the duration of a word spoken in a sentence is influenced by: (1) the grammatical category to which it belongs, and (2) the position of the word in a constituent. Experiment I contained Noun-Verb homophones (e.g. “I saw the coach…” — noun; “I saw him coach…” — verb), in sentences matched for phonetic environment and stress pattern. Results support the notion that Nouns are longer than Verbs in typical sentences. Experiment II, however, demonstrated that the duration of Noun-Verb homophones in matched clause-final position is approximately equal. Experiment III contained transitive and intransitive Verbs in matched sentences. The results of Experiments II and III provided support for a lengthening account based on constituent-final position, while ruling out an account based on a debatable deletion site. Results of Experiment IV generalized the account of constituent-final lengthening for Nouns and Verbs to additional major categories, by comparing the duration of the phrase-initial Adjective two with the phrase-final Adverb too. Finally, Experiment V tested the distinction between minor and major categories. Results demonstrated that the Preposition to is shorter than the Adjective two by approximately 50 percent. Taken in sum, these findings indicate that it is sufficient to make a binary distinction between major and minor categories for purposes of a theory of speech timing and speech synthesis. Durational effects traditionally ascribed to differences within the class of major categories can be accounted for solely in terms of constituent boundaries, already required in the theory to account for three other classes of phenomena.