Hemiretinal differences in face recognition: accuracy versus reaction time

A face-recognition task involving monocular presentation of laterally displaced stimuli yielded a nasal hemiretinal advantage for reaction time for correct identifications, but a temporal hemiretinal advantage for accuracy (d'). These hemiretinal effects, in conjunction with eye dominance, could in principle distort or obscure interpretations of hemispheric processing differences obtained with binocular stimulation.     

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.     

Quantification and semantic memory

Two models are considered for how people verify explicitly quantified sentences, such as All fathers are parents and Some fathers are parents. The models share the same second stage, but have different first-stage mechanisms. In the Predicate Intersection Model, suggested by Meyer (1970), the first stage involves a serial, self-terminating search among names of categories that intersect the predicate category. In the Feature Comparison Model (Smith, Shoben & Rips, 1974a), the first stage involves evaluating the overall relatedness between the subject and predicate categories by comparing their semantic features. To test the models, three reaction time experiments required subjects to verify statements quantified by Some or All. In the first experiment, the semantic relatedness of categories in false Some-statements was varied. Contrary to predictions of the Predicate Intersection Model, related categories increased reaction time for both true and false Some-statements. While the first experiment revealed that All-statements took longer to verify than comparable Some-statements, the second experiment demonstrated that the All-Some difference can be eliminated by presenting both statement types in the same block of trials, also disconfirming the Predicate Intersection Model. Finally, Experiment III examined the meaning of Some-statements in more detail by having subjects interpret the quantifier Some as “some but not all.” With this interpretation, Some-statements took longer to verify than All-statements. Overall the results support the Feature Comparison Model.     

Negative transfer in children's recall of categorized materials

A negative transfer paradigm was used to assess kindergarten, third-, and sixth-grade (approximately 5, 9, and 12 years old) children's use of category relations in lists presented for recall. Negative transfer effects increased with age, with kindergarten children showing no evidence of interference relative to a control group.     

Associative and categorical processes in children's memory: The role of automaticity in the development of organization in free recall

Free recall performance was assessed in children in Grades 3, 5, 7, and 9 (Experiment 1) and adults (Experiment 2) on a list of categorically related words constructed so that some items within a category were highly associated with one another and interitem associations were low among other items (e.g., dog, cat, cow, lion, tiger). Associative relations were used frequently in recall by subjects of all ages, with analyses of interitem latencies and correlations between recall and clustering indicating that organization in recall was based only on associative relations for the third and fifth graders but based on both associative and nonassociative categorical relations for older subjects. Examination of the placement of high associates in recall indicated that seventh- and ninth-grade children were more apt to use associative relations to begin category clusters than were younger children or adults. These children were hypothesized to use the relatively automatic activation of associative relations to instigate categorical organization and to represent a stage in development between nonstrategic younger children and strategic adults. The results were discussed in terms of the role that the automatic activation of semantic memory relations may play in the development of strategic memory organization.