A Bayesian procedure for separately estimating storage and retrieval components of forgetting

A Bayesian procedure was developed to estimate separately the probability of sufficient storage, θ_s, and the probability of successful retrieval, θ_τ, on an individual subject basis. The method involves a probabilistic analysis of the subject's performance on a task that randomly intermixes recall with recognition trials. Two experiments using the Brown-Peterson paradigm were performed to demonstrate and validate the estimation procedure. The experiments showed that both θ_s and θ_τ decrease as a function of increasing retention interval. The results of both experiments suggest the necessity of a two-factor theory for short-term memory.     

Shape constancy and a perceptual bias towards symmetry

In attempting to judge whether a briefly presented rotated figure was symmetrical (circle or square) or asymmetrical (ellipse or rectangle), a bias towards perceiving symmetry was evident. This bias appears to be perceptual rather than judgmental in origin in that it was affected neither by variations in the probability of occurrence of symmetrical figures nor by familiarization with the stimuli. A characterization of the stimulus similarity space based on the shape-slant invariance hypothesis is presented, and a model which incorporates both the similarity space and the symmetry bias is proposed. The model can account for our paradoxical finding that the more asymmetrical some projected images, the more likely they will be perceived as symmetrical. This model can also account for Massaro’s (1973, 1975) results on shape constancy. However, Massaro’s theory was not supported in that extension in depth did not account for increased difficulty of shape judgments.     

Notes on the uses of psychoanalysis for biography

It is the dual aim of this presentation to explore the scope and to define the limits of what psychoanalysis can offer to the field of biography. In pursuit of these goals emphasis is placed upon the influence of the writer's emotional attachment to his subject, which, despite intensive psychoanalytic training and experience, may compromise his objectivity and contaminate his narrative. In addition, attention is drawn to psychological issues in the life of the creative artist which may play a decisive role both in determining the quality of his work and in stimulating its production.     

Cerebral blood flow in normal and abnormal sleep and dreaming

Measurements of regional or local cerebral blood flow (CBF) by the xenon-133 inhalation method and stable xenon computerized tomography CBF (CTCBF) method were made during relaxed wakefulness and different stages of REM and non-REM sleep in normal age-matched volunteers, narcoleptics, and sleep apneics. In the awake state, CBF values were reduced in both narcoleptics and sleep apneics in the brainstem and cerebellar regions. During sleep onset, whether REM or stage I-II, CBF values were paradoxically increased in narcoleptics but decreased severely in sleep apneics, while in normal volunteers they became diffusely but more moderately decreased. In REM sleep and dreaming CBF values greatly increased, particularly in right temporo-parietal regions in subjects experiencing both visual and auditory dreaming.