A developmental evaluation of the role of word shape in word recognition

Fourth- and seventh-grade children and college-age adults proofread passages typed either in lowercase or in all capital letters. Words were misspelled by deleting one of four letters, s, c, k, or p, that have similar features in lowercase and uppercase. Proofreading errors decreased with age and increasing reading ability, but all of the subjects were sensitive to changes in word shape--they missed more words with deletions of s or c than k or p in the lowercase passage but not in the all-capitals passage. These findings indicate that word shape is an important variable in recognizing familiar words, even for young readers.     

The role of inhibition in a spreading-activation model of language production. II. The simulational perspective

This is the second part of a project aimed at establishing the role of lateral inhibition in spreading-activation models of language production. While the first part (Berg &; Schade, 1992) reviewed the psycholinguistic evidence for inhibition and established that indeed inhibition takes place, this paper addresses the issue from the implementational perspective. A series of computer simulations are reported in which spreading-activation models with or without inhibition are directly contrasted. The performance of the competing models is evaluated against two sets of criteria. On the more technical side, the “heat death” and the selection problems have to be solved. That is, the target must have a high and the nontarget units a low level of activation. Additionally, there are certain empirical effects from the production literature which may serve as test cases for deciding between the rival models. The results of the simulations indicate that only the inhibition-based model proves capable of meeting all challenges. All inhibitionless variants fail in one or more respects. It is further shown that the need for the inhibitory component increases with the size of the processing network and that one well-known production model can do without lateral inhibition only at the expense of introducing a concept which resembles inhibition in its effect but cannot replace it.     

Probabilistic causality reexamined

According to Nancy Cartwright, a causal law holds just when a certain probabilistic condition obtains in all test situations which in turn satisfy a set of background conditions. These background conditions are shown to be inconsistent and, on separate account, logically incoherent. I offer a corrective reformulation which also incorporates a strategy for problems like Hesslow's thrombosis case. I also show that Cartwright's recent argument for modifying the condition to appeal to singular causes fails.Proposed modifications of the theory's probabilistic condition to handle effects with extreme probabilities (0 or 1) are found unsatisfactory. I propose a unified solution which also handles extreme causes. Undefined conditional probabilities give rise to three good, but non-equivalent, ways of formulating the theory. Various formulations appear in the literature. I give arguments to eliminate all but one candidate. Finally, I argue for a crucial new condition clause, and show how to extend the results beyond a simple probabilistic framework.     

The tunnel effect,Gibson's perception theory,and reflective seeing

Summary Subjects can have continuous visual experience of an object's movement across a display though the movement's middle phase takes place behind an opaque screen. The present article considers explanatory issues pertaining to this so-called, tunnel effect, with special reference to Gibson' s perception theory and the visual activity that I have been calling reflective seeing. Among the issues discussed are the following. (a) In the tunnel experiments, I suggest, there occur both persisting perception, as Michotte held, and persistence perception, as Gibson held. The subjects pick up stimulus information that allows visually experiencing the object's going out of sight at one edge of the screen and coming back into sight at another edge of the screen; the subjects have visual experience of the continued existence and movement of the object while it is out of sight. Moreover, persistence of perceptual experience is involved: when the object goes out of sight, the subjects' visual experience of its movement goes on. (b) I also argue that the tunnel effect is a phenomenon of both straightforward and reflective seeing. Adopting a phenomenal attitude, as one does when reporting one's perceptual experience, one still sees movement taking place on the other side of the screen, as one does in straightforward seeing. However, whereas straightforward seeing does not give inner awareness of visual experience, the subjects in the tunnel experiments report visually experiencing the object's movement while also visually experiencing the opaque screen in front of it as opaque. I argue that these reports, and those about the object's going out of and coming back into sight, must be based on the kind of visual experience that is part and product of reflective seeing.     

Relation of cognitive operational performance to comprehension and production of dimensional adjectives

This study compared normal developing children, aged 34 to 51 mo., on comprehension and production of relative dimensional adjectives using object manipulations in a close elicitation procedure and on Piagetian operational tests of conservation of continuous quantity, length, reversibility and seriation. Analysis indicated a significant difference on the expressive language performance of the transitional and the concrete operational children over the preoperational children, but no significant differences occurred between the first two groups. Children who performed better on seriation were significantly better on expressive language performance. Children classified as operational for length performed better on all language measures than those classified as nonoperational. Reversibility and conservation of a continuous quantity did not differentiate children.     

On believing,saying and expressing

Examines the connections among believing, saying, and expressing in situations where the sentence used is a declarative sentence containing at least one proper name. Proposes a new way of understanding these connections. Develops an argument for the thesis that, although we typically believe the singular propositions expressed by our uses of name sentences, we rarely use such sentences because we believe those propositions.     

Timed magnitude comparisons of numerical and nonnumerical expressions of uncertainty

Two experiments involving paired comparisons of numerical and nonnumerical expressions of uncertainty are reported. Subjects were timed under two opposing sets of instructions ("choose higher probability" vs. "choose lower probability"). Numerical comparisons were consistently faster and easier than their nonnumerical counterparts. Consistent distance and congruity effects were obtained, illustrating that both numerical and nonnumerical expressions of uncertainty contain subjective magnitude information, and suggesting that similar processes are employed in manipulating and comparing numerical and verbal terms. To account for the general pattern of results obtained, Holyoak's reference point model (1978) was generalized by explicitly including the vagueness of the nonnumerical expressions. This generalized model is based on the notion that probability expressions can be represented by membership functions (Wallsten, Budescu, Rapoport, Zwick, & Forsyth, 1986) from which measures of location for each word, and measures of overlap for each pair can be derived. A good level of fit was obtained for this model at the individual level.