Affordances and infant learning: A reply to Horowitz

We reply to three major points made by F. Horowitz (1983, Developmental Review, 3, 405–409) in her commentary on the ecological approach to infant knowing presented by E. Goldfield (1983, Developmental Review, 3, 371–404). We first clarify the relation between perceiving and acting from an ecological perspective, and distinguish between affordances as environmental properties scaled to the perceiver/performer and representations as mental structures. We then present a critique of the process of association offered by Horowitz as an explanation of infant learning. Association fails to specify the constraints on what is learned, while the ecological process of noticing affordances, presented by Goldfield, considers such constraints. We conclude by presenting operational criteria for measuring affordances and evidence that perception is scaled to the perceiver/performer.     

Temporal aspects of retrieval in short-term serial retention

In three experiments, temporal properties of memory retrieval are studied. Latency of positionally probed recall of a single item is measured as a function of its serial position (SP) in a serial list. The requested SP is indicated by a positional probe, presented immediately after the list. For two organizational structures of the list (i.e., grouped vs. ungrouped lists) the experiments study the effects of precueing the probe position briefly before probe presentation, the cue signal indicating the SPs relevant for recall. The problem of confounded effects on latency of requested SP and of probe-signal location is also investigated. A bow-shaped SP-curve is found for ungrouped lists; precueing reduces RT but does not affect the bowed shape. This argues against selective confounding effects of spatial probe position and also suggests that precueing preactivates memory access. Grouping the items into two sublists eliminates precueing effects for items around the group boundary. Furthermore, precueing is detrimental when SPs at opposite ends of the list are precued. This suggests that the available points of memory access can only be utilized one at a time, so that precueing is not beneficial when the item cannot be reached via the preactivated point. Although the notion of single access to memory is in accord with both positional cueing theory and non-associative hierarchical theories (e.g., Estes 1972), various details of the results are in favor of the first type of explanation.     

Residual ability to use grapheme-phoneme conversion rules in phonological dyslexia

A case of acquired phonological dyslexia is described (P.M.). The patient was encouraged to read nonwords by analogy with real words, i.e., by changing phonemes in real words to produce pronounceable nonwords. P.M. was able to perform this task suggesting that he retained some ability to use grapheme-phoneme conversion rules. On the basis of P.M.'s performance an additional connection in Morton's logogen model is postulated.     

Sheldon's physical-psychical typology revisited

In order to clarify some of the general findings in the literature with respect to relationships between body type and the personality dimension extraversion/introversion, typical experimental paradigms common to this field were replicated but using the first-order factors (from the R. B. Cattell, H. W. Eber, & M. M. Tatsuoka (1970, Handbook for the sixteen personality factor questionnaire, Windsor: N.F.E.R.) analysis) that load on this continuum rather than the continuum itself. Use was made of standard statistical procedures as well as discriminant analysis. The most noteworthy finding was that subjects were able to utilize the first-order factor structure for the continuum extraversion/introversion in a discriminating manner and to assign such factors in a fairly clear-cut way to three extreme body types. Personality appraisals of the mesomorphic body type and an ideal type (composed by the subjects) were shown to be virtually identical. The most positive extravert characteristics were assigned to the endomorph body build and the most positive introvert characteristics to the ectomorph. No differences in personality appraisals by male (n = 50) and female (n = 50) subjects with the exception of factor Q₂ by the ectomorphic body type were found. Both male and female subjects showed a preference for the (male) mesomorphic body type although significant differences between male and female subjects in the pattern of their distribution of preferences over the three body types were found. While the results confirm previous findings, they also extend them by the use of a first-order factor structure for the continuum extraversion/introversion and by the introduction of the explanatory concepts “extravert of affect” and “extravert of action.”     

A new processing model for predicting performance on Pascual-Leone's test of M-space

A new model is proposed for explaining children's performance on Pascual-Leone's test of M-space. The model differs from Pascual-Leone's in three regards. (1) It assumes that children do not stop sampling a compound stimulus until every simple stimulus in their field of attention has already been noticed and responded to. (2) It assumes that the probability of sampling different combinations of simple stimuli conforms to the laws of Maxwell-Boltzman statistics rather than Bose-Einstein statistics. (3) It assumes that children's ability to detect all the simple stimuli in a compound stimulus is highly dependent both on the relative saliencies of the simple stimuli and on the length of time for which the compound stimulus is exposed. Using the developmental values of M hypothesized by Pascual-Leone, and standard techniques of computer simulation, the new model is used to generate theoretical performance curves for children at four different age levels and seven different levels of stimulus complexity. It is shown that the predicted performance curves for an exposure time of 5 sec provide a reasonable fit to the data originally reported by Pascual-Leone (1970), and that the predicted performance curves for an exposure time of 10 sec provide a reasonable fit to data obtained more recently by Parkinson (1976). Finally, it is shown that the order of children's responses as well as the number of their responses can be predicted. Two conclusions are drawn. (1) The new processing model offers a viable alternative to the model originally proposed by Pascual-Leone. (2) Regardless of which processing model is employed, the M-values originally postulated by Pascual-Leone are valid.     

Three types of schemata in children's recall of cohesive and noncohesive text

Children, ranging in ages from 7.3 to 9.6 years, were identified according to the type of schemata structure they used to recall picture sequence events. These children were then required to recall several written text passages representing four different conditions: (1) theme first paragraphs, (2) theme final paragraphs, (3) paragraphs with no theme but having thematic structure, and (4) paragraphs with no theme and no thematic structure. It was found that the manner and the amount of the child's recall were a function of how the child's schemata structure interacted with a given paragraph structure. The implications of these findings are discussed in terms of the generally unquestioned assumption that only one “ideal” text grammar is needed to describe children's schemata for processing test.     

Resolution time and the coding of arithmetic relations on supraliminally different visual extents

Comparison time for pairs of vertical-line stimuli, sufficiently different that they can be errorlessly discriminated with respect to visual extent, was examined as a function of arithmetic relations (physical ratio and difference) on members of the pair. Arithmetic relations are coded very precisely by judgment time: Responses slow as stimulus ratios approach one with difference fixed, and as stimulus differences approach zero with ratio fixed. Most models which assume a simple (Difference or Ratio) resolution rule operating on independent sensations require judgment time to depend on either ratios or on differences but not on both. Further tests showed both an index based on median judgment times and a confusion index based on pairs of observed judgment times, satisfied the requirements for a Positive Difference Structure. One representation of these data, which remains acceptable through all analyses, is a Difference resolution rule operating on sensations determined by a power psychophysical function with β < 1. Specifically, L(x, y) = F{ψ(x) ? ψ(y)} + R, where L(x, y) is the judgment time with the stimulus pair x and y, ψ(x) = Ax^β + C, R is a positive constant, and F is a continuous monotone decreasing function.     

Effect of thought-stopping on thoughts,mood and corrugator EMG in depressed patients

The immediate effects of thought-stopping applied to depressive thoughts were compared to those of a control procedure in a group of depressed psychiatric day-patients. Thought-stopping had only a weak effect on average in reducing the frequency of depressive thoughts, and no significant effects on depressed mood or corrugator EMG. A small significant effect on anxious mood appeared related to non-specific factors. The results raise the possibility that thought-stopping may have little specific effect in reducing the frequency of unwanted thoughts. Corrugator EMG was significantly related to the frequency of spontaneously occurring depressive thoughts both between and within subjects.