Effects of content on inclusive disjunction reasoning

An experiment is reported which establishes that inclusive disjunction arguments embedded in concrete content are not always easier to reason with than those involving abstract content. The subjects had to assess conclusions drawn from pairs of premises such as “Either Joan is intelligent or she is rich (or both); Joan is intelligent” or “Either Joan is intelligent or she is rich (or both); Joan is not intelligent”. The terms in the disjunctive premise were varied systematically across three content dimensions (i.e. compatible, abstract and contradictory). An analysis of variance revealed significant differences according to both principle of inference and type of content, and a significant interaction between these factors. The results demonstrated that semantically incompatible premise content had a marked influence on comprehension of inclusive disjunction reasoning schemes. The response patterns suggest that these reasoning schemes invited erroneous judgments based on other logical connectives.     

Bias in Conditional Inference: Implications for Mental Models and Mental Logic

Three experiments are reported in which subjects are given the opportunity to make any of the four inferences associated with conditional statements: modus ponens (MP), denial of the antecedent (DA), affirmation of the consequent (AC), and modus tollens (MT). The primary purpose of the research was to establish the generality and robustness of polarity biases that may be occasioned by systematic rotation of negative components in the conditional rules. In Experiments 1 & 2, three forms of conditionals were used: “if (not) p then (not) q”, “(not) p only if (not) q” and “(not) q if (not) p”. Experiment 1 used a conclusion evaluation task, whereas Experiment 2 used a conclusion production task. In Experiment 3, thematic conditionals were presented with and without a preceding scenario.

The biases investigated were (a) affirmative premise bias—the tendency to draw more inferences from affirmative premises and (b) negative conclusion bias—the tendency to draw more inferences with negative conclusions. The suggestive evidence for affirmative premise bias in the literature was not supported: very little evidence was found for it in the current experiments. Robust findings of negative conclusion bias were, however, found across the three experiments, although the bias was mostly restricted to DA and MT inferences. This suggests that the bias is best regarded as a difficulty with double negation.

The results are discussed with respect to both the mental logic and mental model accounts of propositional reasoning. Neither theory as currently formulated can explain all of our findings, although a plausible revision of each is considered.     

Syntactic form and semantic function

The experiments reported here were designed to investigate the effects on linguistic performance of varying the interaction between the syntactic form of sentences and their semantic function. The experimental task required subjects to decide whether pairs of sentences had the same or a different meaning. The results of Experiment I confirmed the prediction that the times taken to decide about pairs of affirmative and negative sentences would be shorter when the negative was performing its natural function of signalling a change of meaning. To a lesser extent, performance on pairs of active and passive sentences was facilitated when the two sentences meant the same thing. These results were found both with “meaningful” sentence material and with abstract x-y sentences. A second experiment provided a control for the possibility that the results were due to syntactic derivational factors rather than to the semantic function interaction.     

Shorter articles and notes the interpretation of the passive voice

It was hypothesized that sentences in the passive voice emphasize the importance of the things referred to by their grammatical subjects to a greater extent than sentences in the active voice. Each subject had to produce simple diagrams to represent two sentences, one active and one passive, and it was assumed that the size of areas in these diagrams could be taken as an index of importance. In Group EQ, the sentences specified an equivalent arrangement of colours, e.g. “Red follows Blue,” “Blue is followed by Red”; in Group CO, they specified converse arrangements, e.g. “Red follows Blue,” “Red is followed by Blue.” The predictions, that (i) the subjects of all sentences would tend to be represented as larger than the objects, and that (ii) the subjects of passives would be represented as larger than those of actives, were confirmed.     

Reasoning about a rule

Two experiments were carried out to investigate the difficulty of making the contra-positive inference from conditional sentences of the form, “if P then Q.” This inference, that not-P follows from not-Q, requires the transformation of the information presented in the conditional sentence. It is suggested that the difficulty is due to a mental set for expecting a relation of truth, correspondence, or match to hold between sentences and states of affairs. The elicitation of the inference was not facilitated by attempting to induce two kinds of therapy designed to break this set. It is argued that the subjects did not give evidence of having acquired the characteristics of Piaget's “formal operational thought.”     

The four-card problem and the generality of formal reasoning

Three experiments were designed to investigate the failure of intelligent adults to solve an apparently simple problem of formal reasoning devised by Wason. Both the mode of presentation and the type of material reduced the difficulty of the problem, while retaining its essential form. However, success on the original problem remained at a low level, even when subjects had attempted an easier version and had been given an explanation.

These results enable one to reject a “strong” formulation of Piaget's theory of formal reasoning. A “weaker” formulation is suggested as a basis for further research.     

Mental models and temporal reasoning

We report five experiments investigating reasoning based on temporal relations, such as: “John takes a shower before he drinks coffee”. How individuals make temporal inferences has not been studied hitherto, but we conjectured that they construct mental models of events, and we developed a computer program that reasons in this way.As the program shows, a problem of the form:

1. a before b

2. b before c

3. d while b

4. e while c

What is the relation between d and e?

where a, b, c, etc. refer to everyday events, calls for just one model, whereas a problem in which the second premise is modified to c before b calls for multiple models because a may occur before c, after c, or at the same time as c.

Experiments 1–3 showed that problems requiring one mental model elicited more correct responses than problems requiring multiple models, which in turn elicited more correct answers than multiple model problems with no valid answers. Experiment 4 contrasted the predictions of the model theory with those based on formal rules of inference; its results corroborated the model theory. Experiment 5 confirmed that a premise leading to multiple models took longer to read than the corresponding premise in one-model problems, and that latency to respond correctly was greater for multiple-model problems than for one-model problems. We conclude that the experiments corroborate the mental model theory.     

Are professors likely to report having “beliefs” about the intelligence and competence of students who stutter?

Some university students who stutter report that they avoid participating in class discussions and talking with professors because they believe that if their professors find out they stutter, the professors are likely to view the students as being less intelligent and/or competent than they otherwise would. The purpose of this study was to determine whether professors, as a group, are likely to report such beliefs. A random sample of 87 professors at Marquette University, Indiana University of Pennsylvania, and the State University of New York at Stonybrook rated “A Student Who Stutters” on each of 81 seven-point, bipolar semantic differential scales, including intelligent/unintelligent and competent/incompetent. Although there was considerable scatter in their ratings for the majority of the scales, 85 of the 87 rated the student at the center or “positive” end of the intelligent/unintelligent scale and 83 of the 87 did so on the competent/incompetent one. Assuming that the attitutes reported by the professors reflect their “real” ones, these data suggest that many—perhaps the majority—do not have negative attitudes about the intelligence and competence of their students who stutter.     

Auditory and visual word-stem completion: Separating data-driven and conceptually driven processes

Two experiments investigated the contributions of data-driven and conceptually driven processing on an implicit word-stem completion task. In Experiment 1, individual words were studied either visually or auditorily and were tested using either visual or auditory word-stems. Keeping modality the same from study to test led to more priming than did changing modality, but there was reliable cross-modal priming. In Experiment 2, subjects read sentences like The boat travelled underwater and inferred the subject noun (i.e. “submarine”) or sentences like The submarine travelled underwater and categorized the subject noun (i.e. “boat”). At test, there was reliable priming for both actually read nouns and inferred nouns. In addition, a modality effect was evident for the actually read nouns but not for the inferred nouns. Taken together, these results imply that there is a basic conceptually driven contribution to priming plus an additional contribution of data-driven processing when surface form is the same at study and test.     

Cognitive overload and orthographic errors: When cognitive overload enhances subject-verb agreement errors. A study in French written language

Three experiments were carried out to test the hypothesis that cognitive overload enhances the occurrence of subject-verb agreement errors in French. Highly educated adults were presented orally with sentences they were required to write down. The sentences were of the types “N1 de N2 V” (Noun 1 of Noun 2 Verb: Le chien des voisins arrive/The neighbours' dog is arriving) versus “Prl Pr2 V” (Pronoun 1 Pronoun 2 Verb: Il les aime/He likes them). In these sentences, N1 (Pr1) and N2 (Pr2) matched or mismatched in number. In the three experiments, the sentences had to be recalled either in an isolated condition (i.e. every presented sentence had to be immediately recalled) or with a concurrent task: click counting (Experiment 2) or serial recall of series of five words presented immediately after the sentences (Experiments 1 and 3). Participants showed errors when performing two concurrent tasks and almost no error when recalling isolated sentences. As expected, errors occurred when N1 (Pr1) and N1 (Pr2) mismatched in number. The results are consistent with our hypothesis and with a functional approach of written composition.     

Short report: Is spatial information encoded automatically in memory?

A dual-task paradigm was used to test Hasher and Zacks' (1979) hypothesis that spatial memory is automatic. Subjects saw two sets of 16 words each, the words being presented singly in random corners of a monitor screen. They were asked to remember the words and the corner in which each word was shown. In addition, subjects were given a concurrent task to perform. This task was either “easy” (counting aloud by ones) or “difficult” (counting aloud by sevens). Attention was focused either on the memory task or on the counting task. Word recognition was better when subjects carried out the easier competing counting task and when subjects concentrated mainly upon remembering the words and their positions. Contingent spatial memory was unaffected by either manipulation, supporting the hypothesis that spatial memory is automatic.     

Speech—Language clinicians'' and university students'' impressions of women and girls who stutter

To identify impressions speech—language clinicians and university students have of females who stutter, a 47-scale semantic differential form was administered to members of each group to obtain their responses to eight hypothetical constructs, i.e., “A Girl,” “A Girl Who Stutters,” “A Boy,” “A Boy Who Stutters,” “A Woman,” “A Woman Who Stutters,” “A Man,” and “A Man Who Stutters.” Both groups were found to possess negative stereotypes for all four categories of stutterers. The nature of the stereotypes appeared to be influenced by a stutterer's gender and relative age. Clinicians considered stuttering to exert a stronger negative impact on females and on children. Their strongest stereotype was of “A Girl Who Stutters.” University students considered stuttering to exert a stronger negative impact on males. Their stereotypes of stutterers seemed unaffected by the relative age of the stutterer. Their strongest stereotype was of “A Man Who Stutters.” Several theoretical and clinical implications of these findings are discussed.     

An observation on set and visual comparison processes

Tasks involving the comparison of sequentially presented stimulus items to determine identity have generally only required interpretation in terms of simple matching. Some studies have attempted to show effects of selective set in these tasks but with little success except in tasks involving comparison of sentences with pictures. By simplifying the task a reliable set effect is demonstrated, showing that a mismatch of certain stimulus attributes only has an identifiable effect on a subject's reaction-time if he may reasonably be supposed to know that the attribute is critical and is set to examine stimulus items for the attribute. Such conditions result in a relatively fast judgement. The finding suggests that the sequential “same“/“different” judgement is a richer source of data concerning recognition and comparison than has been supposed.     

The effect of an irrelevant dimension on “same-different” judgements of multi-dimensional stimuli

Subjects made “same”-“different” judgements of simultaneously presented pairs of visual stimuli which could vary either in shape and colour independently, or in shape alone. In both conditions only shape was relevant to the “same”-“different” judgement. In the former condition “same” and “different” reaction times (RTs) were shorter when the states (“same” or “different”) of the relevant and the irrelevant dimension, colour, were the same. This result is interpreted as support for either a perceptual or a response interference hypothesis. The presence of an irrelevant dimension did not appear to affect differentially “same” and “different” judgements. The need for a re-evaluation of the results from other studies of multi-dimensional stimulus discrimination is discussed.     

Syntactic structure and the garden path

The experiment investigated locally ambiguous English sentences containing “complement” verbs such as believe, which can be followed either by a direct object or by a complement clause. These two sentence types were compared with unambiguous sentences in which the complement clause was introduced by the word that. Subjects processed numerous examples of these sentences in a word-by-word self-paced reading task. At the disambiguation point after the ambiguous noun phrase, longer reading times were obtained for reduced complement constructions compared with direct object sentences. Such an effect has been attributed to the operation of the parsing principle Minimal Attachment (Frazier and Rayner, 1982). This principle predicts that subjects assume falsely that the noun phrase after the complement verb in the reduced complement constructions is the direct object, resulting in the need for subsequent structural reanalysis. However, longer times in the disambiguating zone were also found for the unambiguous that complements. Thus, the complexity difference seems not to represent “garden-pathing” as a result of the operation of Minimal Attachment, but may instead reflect the extra complexity caused by having to handle two sets of clausal relations instead of just one.     

The twelfth Bartlett memorial lecture: The role of single neurons in the psychology of perception

I feel deeply honoured by your invitation to give the Bartlett lecture, and am especially glad to do so in Holland, the home of so many distinguished psychologists of sensation and perception. And there is a third reason why it has given me much pleasure, for Sir Frederick Bartlett was one of those who had an important influence on the direction of my career some 40 years ago. I had to decide whether to spend my last year at Cambridge reading psychology or physiology, so I attended a short course of introductory lectures he gave in July. About half a dozen of us sat on upright wooden chairs circled around him as he sat in an armchair, smiling benignly. The first thing he did was to tell us to close our notebooks, for he was not going to say anything that would help us to pass any exams. And I believe the very last words of his last lecture were, “So you see it is all very difficult”. I was very glad he said that, for I had in fact found it all very heavy going: my brain seemed always to be lost in clouds of uncertainty when “remembering”, “thinking”, or “perceiving” were mentioned, because there was no conceptual framework for these processes except the words themselves and others spun around them. What I was looking for were the definable quantities of physics, chemistry and even physiology, these I could handle conceptually in their geometric and functional interactions, whereas I always find a purely verbal argument about abstractions difficult to follow and impossible to believe. So this lack of any nonverbal conceptual framework was very painful.

There was one phrase I think I recall him using that particularly aroused my interest-“the effort after meaning”; intuitively this seemed to be very important, but however much effort I made the meaning never quite emerged. I had almost decided that my mistrust of words made me unsuited to a career in psychology, but all the same I put my problem about “physiology or psychology” directly to Bartlett. After finding out that I was mainly interested in problems of sensation and perception, he said he thought that E. D. Adrian's research over the last 20 years had made more difference to that subject than any results obtained from within psychology itself.     

Visual storage or visual masking? an analysis of the “retroactive contour enhancement” effect

Standing and Dodwell (1972) reported that a contoured target stimulus which is only poorly identified when exposed briefly against a steady background field can be identified accurately if the field is terminated shortly after target offset. This observation was confirmed and, in addition, it was shown that target identification is enhanced when the field is initiated shortly before target onset. Furthermore, it was demonstrated that a continuous background field is not essential for either effect. It was argued that these “retroactive” and “proactive” enhancements of target identification were due to a complex interaction among forward, backward, and simultaneous masking.     

Suppression effects in rhyme judgement tasks

Orthographic and phonological similarity were orthogonally manipulated in a rhyme judgement task. The effects were assessed of paced versus very rapid articulatory suppression on subjects' ability to make rhyme judgements when pairs of words were presented either simultaneously or successively. It was found that there were consistent suppression effects on the accuracy of subjects' judgements to visually similar non-rhyming pairs (e.g. “pint-tint”), visually dissimilar rhyming pairs (e.g. “fare-wear”) and visually similar rhyming pairs (e.g. “fall-tall), regardless of mode of presentation or speed of suppression. The size of the suppression effect was greatest for the visually similar non-rhyming word pairs. It was argued that subjects need to carry out a recheck for phonological similarity when word pairs are visually but not phonologically similar, and that encoding the words in articulatory form is particularly beneficial for making accurate rhyme judgements to such pairs.     

A study of the effect of structural information and familiarity in form perception

Two experiments were carried out to investigate the influence of structural information and familiarity on the processing of visual forms. Pairs of “well” structured and nameable and “poorly” structured and non-nameable fragmented forms were employed as stimuli. The effects of structure and familiarity were assessed by manipulating the visual hemifield of presentation and the task. In Experiment 1 stimuli were judged as being either in the same orientation or mirror-reversed, a task that does not require high-level semantic information to be processed. Experiment 2 required physically identical forms to be matched, which may use either physical or name information. In Experiment 1 “same” judgements were equivalent for both types of stimuli, and “different' judgements were longer for the “poorly” structured (non-nameable) forms. In Experiment 2 there was little overall difference between “well” and “poorly” structured forms, though response times to “well” structured (nameable) forms were slowed for right-visual-field presentations. It is suggested that familiarity may not be sufficient to provide a perceptual advantage for nameable forms, as the advantage for nameable stimuli was confined to “same” judgements in Experiment 1 and response times were shorter for non-nameable stimuli in Experiment 2. Rather, performance depends upon factors such as the computation of global shape (due to structural properties of collinearity and closure) and on the use of different kinds or representations (physical versus name) in matching.