The “lag effect” in dichoptic viewing

Ten subjects were asked to report both of two different consonant-vowels (CVs) presented to the same foveal area, but in different eyes (“dichoptically”). Stimuli were presented at stimulus-onset asynchronies (SOAs) ranging from 0 to 150 msec in 25-msec steps. Correct identifications were significantly depressed for the eye receiving the leading stimulus at SOAs of 25 to 75 msec. Monoptic data from three subjects indicated no significant reductions in correct identification as a function of SOA. The dichoptic results can be understood in terms of current theories of visual backward masking and are similar to the “lag effect” observed with dichotic listening to speech stimuli. Similarity of results for the two modalities suggests a similar “two-process” explanation may underlie both phenomena.     

Intelligence and short-term memory: A clandestine relationship

Five possible mechanisms are considered as being responsible for the systematic variation of serial STM with IQ, namely rehearsal maintenance, chunking, access, encoding of item and/or order information, and trace persistence. A STM/IQ correlational study is reported. It was concluded from analysis of a correlation matrix, and from earlier reported data, that the encoding of items-in-order into an already loaded store appears to be the critical mechanism in determining IQ-related individual differences in STM performance, at least in children. The implications of individual difference data for models of STM are also discussed.     

A case of prosopagnosia with some preserved covert remembrance of familiar faces

This paper presents the detailed analysis of a case of prosopagnosia in a 54-year-old male farmer following bioccipital vascular disease. In-depth clinical investigations confirmed the diagnosis of prosopagnosia and revealed the absence of any associated defect, except for a slight aspecific disturbance of the short-term memory. Further study of this case indicated that the trouble was not concerned with the class of complex visual stimuli, was not even concerned with facial expressions or unknown faces, was not a perceptual defect, but was related mainly to the operation of individualization. The memory hypothesis was thus retained and supported. Moreover, exploration of the difficulty indicated that the deficiency was limited to defective access to conscious information concerning faces and information associated with these faces (name, context, etc.), effectively stored in memory.     

Perceptual categorization in the cerebral hemispheres

The suggestion of a functional hemispheric dissociation in performing perceptual categorization was examined in two tachistoscopic experiments with normal adults. Subjects were required to match physically identical or similar, but nonidentical, pictures of animals. The first experiment showed no hemispheric difference and indicated that both hemispheres could resort to two different types of categorization process as a function of the simultaneous or delayed mode of presentation of the stimuli. In the second experiment, the viewing conditions were manipulated so as to afford a reduced amount of stimulus energy, and a significant left-visual-field advantage was then obtained. The results are discussed with respect to models of information processing in the cerebral hemispheres, and in relation to impairments in object recognition following brain damage.     

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.     

Does everybody like a liker?

The primary hypothesis examined was that people giving positive evaluations are themselves regarded as more attractive than when they give negative evaluations. This research tests whether this holds when reciprocity is not at issue. Subjects in six experiments were presented with stimulus persons who varied in the proportion of positive to negative evaluations they gave of various attitude objects (political figures, cafeteria workers, cities, movies, and college courses). Giving predominantly positive evaluations did in fact lead to greater liking of the stimulus person in each experiment. This finding held over (1) audio or written interviews with the stimulus persons, (2) a variety of classes of attitude objects, and (3) both within-subject and between-subject designs. Greater liking for likers occurred even controlling for attitude similarity.