Evidence for an integration theory of visual masking

When letters are superimposed upon a pattern of black and white squares, they are easier to identify when the pattern is regular than when it is random. If backward masking consists of the superimposition of a masking pattern upon the decaying visual trace of a target display, a regular pattern should be less effective as a backward mask than a random pattern. This was found to be so for both multiple-letter and single-letter displays. This result is predicted by an integration theory of visual masking but not by an interruption theory.     

Hue discrimination as a function of stimulus luminance

The relation between hue discrimination and stimulus luminance was investigated. It was found that discrimination was best at the highest luminance and deteriorated at the lowest, except in the yellow region.     

Pigeon concept formation: successive and simultaneous acquisition

Pigeons were trained to discriminate the presence of one or more human forms in displays projected on a panel above the response key. This task was mastered, although imperfectly, with successive and with simultaneous presentations of positive and negative instances. The course of acquisition of the discrimination was similar for the two training procedures. Animals were able to transfer the discrimination from the successive to the simultaneous situation. Various tests were carried out to control for artifactual cues on which the discrimination might have been based. The discrimination was maintained when new displays were presented, when reinforcement was omitted, and when displays were inverted 180°. Animals were also able to discriminate between pairs of displays that were identical, except that one member of the pair contained a human form. The research extends the techniques used by Herrnstein and Loveland (1964), and confirms their finding that pigeons can master the concept of “person-present” in a visual display.     

Attributions for negative life events and depression: the role of perceived control

Although perceptions of control occupied a central role in the development of learned helplessness theory, recent helplessness research has not considered controllability judgments when relating attributions to depression. Supporting the importance of this construct, the research discussed in this article found evidence that judgments of control interact with other attributions in predicting depression. Specifically, in a prospective study of stress and well-being in adolescence, internal, stable, and global attributions for negative events attributed to uncontrollable causes were found to be positively related to increases in depression (as predicted by the reformulated helplessness theory), but internal and global attributions for negative events attributed to controllable causes were found to be inversely related to increases in depression. The discussion considers the implications of the findings for understanding the nature of the relation between attributions for naturally occurring life events and depression.     

Peer interactions of normal and attention-deficit-disordered boys during free-play,cooperative task,and simulated classroom situations

Groups of 30 ADD-H boys and 90 normal boys were divided into 30 mixed dyads composed of a normal and an ADD-H boy, and 30 normal dyads composed of 2 normal boys. Dyads were videotaped interacting in 15-minute free-play, 15-minute cooperative task, and 15-minute simulated classroom settings. Mixed dyads engaged in more controlling interaction than normal dyads in both free-play and simulated classroom settings. In the simulated classroom, mixed dyads completed fewer math problems and were less compliant with the commands of peers. ADD-H children spent less simulated classroom time on task and scored lower on drawing tasks than normal peers. Older dyads proved less controlling, more compliant with peer commands, more inclined to play and work independently, less active, and more likely to remain on task during the cooperative task and simulated classroom settings. Results suggest that the ADD-H child prompts a more controlling, less cooperative pattern of responses from normal peers.     

Is the holocaust relevant to sociobiology?

Sociobiologists have emphasized that altruism and benevolent behavior are part of the genetic repertoire of most animals and certainly of man. They have constructed a theory of ethics as a biological phenomenon without reference to the concept of evil. It is concluded here however, that holocaust behavior is not equivalent to the natural manifestation of an incompletely tamed animal flashing its teeth. Biologists have been too rigid in trying to equate ethical behavior with social behavior. The added dimension of ethical behavior is a special kind of sensitivity to the needs of others, just as evil is the total lack of it. The evolution of this moral sense may itself have important selective value for the human species, whose survival depends on creating maximal diversity in its gene pool.     

Book reviews

GEOGRAPHY, R. L. and GOMBRICH, E. H. (Eds). Illusion in Nature and Art. Gerald Duckworth and Co Ltd. 1973. Pp. 288. £7.50/£3.25.

HARTMANN, E. L. The Functions of Sleep. London: Yale University Press. 1974. Pp. 198. £ 3.50.

RADFORD, J. and BURNTON, A. Thinking: its Nture and Devolopment. London: Wiley. 1974. Pp. 440. £ 6.95. Soft cover £ 3.25.

MACE, C. A. Selected Paper. London: Methuen and Co Ltd. 1973. Pp. 420. £ 6.50.

WOLFF, J. G. Language, Brain and Hearing. London: Methuen and Co. Ltd. 1973 Pp. 237. £ 3050.

BATTRO, A. M. Piaget: Dictionary of Terms. Oxford: Pergamon Press Ltd. 1973. Pp. 186. £ 5.75.

MUSSEN, P. H. and ROZENSWEIG, M. R. Annual Review of Psychology. Annual Reviews Inc: Palo Alto, Califonia. Pp. 551. 12.50.     

In defence of iconic memory

According to a model of visual information-processing which originated with Sperling (1960), and which currently enjoys wide acceptance, the contents of brief alphanumeric displays are initially held in a high-capacity fast-decay visual-information store (“iconic memory”). Some of these items are subsequently transferred to a more durable form of storage; the remaining non-transferred items are lost. Observers can select which items are to be transferred on the basis of physical characteristics of the items (such as colour, location, size, shape or brightness).

This model has recently been attacked by Holding (1970, 1971, 1972, 1973), sometimes by claiming that iconic memory does not exist, and at other times by claiming that transfer from iconic memory cannot be selectively controlled by the observer. We argue in this paper that Holding's criticisms are incorrect, and that, even if they were correct, the experiment we report would not be open to objections he has raised concerning previous studies of iconic memory. Despite this, evidence fully supporting the orthodox model was obtained, and we therefore conclude that this model remains tenable.     

Memory of a speaker's voice: Reaction time to same- or different-voiced letters

Subjects were presented with a sequence of two letters, each letter spoken in either a male or female voice. On each trial, the subject was required to indicate, as quickly as possible, whether the two letters had the same name. Reaction times (RTs) were faster for letters spoken in the same voice for both “same” and “different” responses, even when letters were separated by 8 s. These results are incompatible with the notion of physical and name codes in auditory memory since a “different” response should always be based on a comparison of letter names and should not be influenced by voice quality. It was also found that RTs were not influenced by the phonemic distinctive feature similarity of the letters.     

Color name as a function of surround luminance and stimulus duration

A color-naming experiment was performed in which both surround luminance and exposure duration were varied. The data showed substantial effects from these changes; however, none could be interpreted to indicate the presence of a Bezold-Brucke shift or tritanopia.