Comparisons of learning procedures: Effects of constant and random presentations

The retention interval hypothesis (Izawa 1972) was formulated on the basis of retention interval distributions given in random order to account for inconsistent performance differences between anticipation and study-test procedures, which have been regarded as a puzzle for nearly two decades. Under the anticipation procedure a presentation of the stimulus term of a paired-associate (a test event) is immediately followed by a presentation of both stimulus and response terms of the pair (a study event), whereas under the study-test procedure, study and test events are given on separate cycles. The retention interval hypothesis was specifically tested in a situation without any random distributions of the retention intervals i.e., under a constant item presentation order from cycle to cycle, in addition to random presentation orders, in a paired-associate learning experiment, using 80 college students. As predicted by the theory, significantly superior performances were obtained for the study-test method vis-à-vis the anticipation method also under a constant item presentation order. The constant presentation-order- arrangements significantly outperformed the random ones. Directions for further theoretical elaborations are suggested.     

Signing environment in an institution: Teaching sign vocabulary to residents with mental retardation for communication with deaf peers

Two experiments were conducted so that deaf adults with mental retardation could develop their communication skills in an institution. Deaf and hearing residents were taught sign vocabulary using the following four procedures: sign language lessons in a large group, posters, review lessons, and distribution of a sign language book. Experiment 1 was a pilot study to assess the effect of a sign language lesson, and Experiment 2 was a systematic study to evaluate the 4 procedures using a multiple baseline design. Sign language use in natural settings was monitored for 10 months, starting with the first sign language lesson. Results showed that a sign language lesson was an effective way for most hearing residents to acquire expressive signs. Three out of 4 deaf residents learned expressive signs gradually during experiments. In natural settings, hearing residents were seen to use signs spontaneously with deaf residents in many different social contexts. Additional comprehensive assessment was conducted to confirm whether or not residents could understand one another's expressive signs. Seven out of 10 residents showed correct responses more than 80% of the time.     

A test of the differences between anticipation and study-test methods of paired-associate learning

The identity model proposes that anticipation and study-test methods of paired-associate learning differ little in basic acquisition, retrieval, and storage processes per event: study, test, and intervening study and test events of other items plus the intercycle interval. The major difference between the two methods boils down to differential short-term loss over the differential retention interval. When the study-test interval is equated, the identity model predicts no difference between the methods. However, the feedback model predicts superiority for the anticipation method, and the differential acquisition, context effect, or task alternation models predict superiority for the study-test method. An experimental test utilized (nearly) identical study-test intervals, various materials, and both massed and spaced practice. In 15 out of 16 comparisons, there was no difference between the methods, providing support for the identity model. Within limits, the greater the study-test interval differentials, the greater the advantage for the method with the shorter study-test intervals. Quantitative analyses support the identity model.