A model of empty duration perception

An attempt to construct a general theory of duration perception is presented. First, four experiments are reported in which the supplement hypothesis, on the relation between two or three empty durations, was examined: the subjective duration of a subjectively empty time interval is directly proportional to its physical duration plus a constant of approximately 80 ms. This hypothesis could be applied to the ratio judgments of auditorily marked empty durations between 40 and 600 ms given serially. It could also explain the discrepancies between musically notated rhythms and the corresponding physical performed rhythms in very simple rhythm patterns consisting of three tones. Next, three earlier experiments on discriminations of empty durations marked by sound bursts were also reanalyzed. Within the range 40-600 ms, the absolute just noticeable difference of an empty duration was almost directly proportional to the standard duration plus a constant of about 80 ms. If the supplement hypothesis is accepted, this means that the relative just noticeable difference of the subjective duration was constant. Finally, the processing time hypothesis is presented: subjective duration is directly proportional to the physical time required to process the given empty duration. This processing is considered to begin with the detection of the first marker, and to end approximately 80 ms after the detection of the second marker.     

Analysis of sequence-dependent interactions between transient calcium and transmitter stimuli in activating adenylyl cyclase in Aplysia: possible contribution to CS--US sequence requirement during conditioning

An important recent insight in a number of neurobiological systems is that during learning, individual dually regulated proteins with associative properties function as critical sites of stimulus convergence. During conditioning in Aplysia, the Ca2+ /calmodulin-sensitive adenylyl cyclase (AC) in mechanosensory neurons serves as a molecular site of interaction between Ca2+ and serotonin [5-hydroxytryptamine (5-HT)]-two signals that represent the CS and US in these cells. Conditioning requires that the CS and US be paired within a narrow time window and in the appropriate sequence. AC shows an analogous sequence preference: It is more effectively activated when a pulse of Ca2+ precedes a pulse of 5-HT than when the 5-HT precedes Ca2+. One mechanism that contributes to this sequence preference is that Ca2+/calmodulin binding to AC accelerates the rate of AC activation by receptor-Gs. We have identified two additional properties of AC activation that would cause pairing with Ca2+ preceding 5-HT to be more effective than simultaneous pairing or pairing with the reciprocal sequence: (1) Activation of Aplysia AC by a Ca2+ pulse rose with a delay compared with activation by a 5-HT pulse. (2) A late pulse of Ca2+, which arrived after 5-HT, acted, via calmodulin, to accelerate the decay of AC activation by receptor-Gs. Together, these activation properties of AC may contribute to the CS-US sequence requirement of classical conditioning.     

Perception of political candidates based on their stand on abortion and taxes.

This study investigated whether young voters would vote for and volunteer to work for the election campaign of a presidential candidate, given the candidate's background and positions on two major campaign issues. Findings indicate that, although voter-candidate agreement on a single issue may be enough for a voter to vote for a candidate, agreement on both issues may be necessary before a voter agrees to volunteer to work for the candidate's election campaign.     

Risky aggression in individuals and groups.

This study set out to investigate whether the risky shaft found in group consensus decisions as compared to group members' personal decisions extends to situations that combine risk and aggression. In a between-subjects design, subjects were exposed, either alone or as members of unisex triads, to an experimental task in which the risk entailed severe noxious consequences. The findings show that for both sexes, groups take significantly greater risks than individuals even when risk taking is mediated by aggressive means. The results are seen and discussed as limiting the explanatory scope of the risk-as-a-value hypothesis and as more consistent with the diffusion of responsibility hypothesis.     

Validity of a group measure of individual associative domains

FlekkØy, K. Validity of a group measure of individual associative domains. Scand. J. Psychol., 1973, 14, 96–98.-Number of different responses given to a stimulus word by a group of subjects in a single-word free-association situation (D) has been presumed to be a measure of the magnitude of the associative potential connected with the stimulus word in the individual subject. The study compares D with mean number of different responses given to each stimulus word in a continued association situation (m), and finds no significant correlation (r=-0.04), which is interpreted to mean that D is not a valid measure of individual associative domains.     

Associative frequency and response latency

FlekkØy, K. Associative frequency and response latency. Scand. J. Psychol., 1973, 14, 199–202.MdashWith 176 Norwegian subjects in a single-word free-association experiment, latency of response was found to relate more highly to the number of different words associated with a stimulus word (D), than to the response frequency of the words involved. D is therefore assumed to reflect a basic characteristic of the associative relationship between the stimulus and response words. The inverse relationship between associative frequency and latency is interpreted to mean that frequency reflects some relatively frequent order of preference of possible response words for individual subjects.     

CHANGES IN THE AGGRESSIVENESS OF MICE RESULTING FROM SELECTIVE BREEDING, LEARNING AND SOCIAL ISOLATION

LAGERSPETZ, K. M. J. & LAGERSPETZ, K. Y. H. Changes in the aggressiveness of mice resulting from selective breeding, learning and social isolation. Scand. J. Psychol. 1971, 12, 241–248.–Selective breeding for aggressiveness and non-aggressiveness in mice has now been going on for 19 generations. The aggressiveness score distributions of the males have not changed since the 7th generation. Socially naive male mice which had been living in isolation, had five encounters with submissive males, and five with receptive females. Learning of aggressive and sexual behaviour occurred in males of both the aggressive and the non-aggessive strain. When living in groups, the males of both strains show no aggressiveness towards a submissive opponent. Social isolation for 1–2 weeks greatly increases the aggressiveness level of the animals of the aggressive strain. The effects of grouping is interpreted as social learning of non-aggressive behaviour, the effect of isolation as return of the inter-individually variable aggressiveness level, determined by genetic variation and early experience. Some neurochemical findings are in agreement with the observed behavioural effects.