Unmasking affiliative behavior among juvenile Midas cichlids (Cichlasoma citrinellum)

Adults of the Midas cichlid (Cichlasoma citrinellum) are predominantly normal-colored (N) morphs, although 8% in nature are gold (G) morphs. They tend to mate assortatively by color; that behavior may be influenced by prior experience with parents or siblings or by their own color. A previous experiment indicated that juveniles respond according to a rule that they avoid and behave defensively toward G juveniles and that they consort with and behave aggressively toward N juveniles (Barlow & Siri, 1987). The fear-provoking effect of G may have interfered with more subtle aspects of choice because the 4 treatment fish in each group reacted through the glass barrier to the approach of the subject. In the present experiment such feedback was eliminated by using one-way mirrors. N juveniles reared by normal parents (N X N) differentiated between N and G treatment fish only in that they attacked significantly more toward G; thus their behavior was contrary to that predicted by the fear-provoking effect of gold. The notable effect among juveniles reared by G parents (G X G) was that N spent more time with N and avoided G treatment fish, in keeping with the fear-provoking effect of gold. The results are discussed in terms of the differences in experiences between juveniles reared N X N, all of which were themselves N, and those reared G X G, consisting of both color morphs. Despite the differences in the two experiments, the main conclusion remains in place: Affiliative responses of juveniles, as measured in these tests, do not predict choice of mate among adults.     

The relation of field dependence to signal detection while imaging

Twelve field-dependent (FD) and 12 field-independent (FI) males were administered 260 trials of a signal detection task in four phases. Signal type (auditory, visual, or no signal) was crossed with four sets of imaging treatments (pure visual representations, pure sounds without visual counterparts, and two sets representing sounds with visual counterparts). Detection of a signal in isolation was 90% accurate, as was the detection of no signal while imaging. Cross-modality imaging interfered with detection of the stimulus but to a significantly lesser extent than did same-modality imaging. In all detection/imaging treatments, FIs were significantly more sensitive to the signal than were FDs; however, FDs and FIs did not differ in accuracy of detecting isolated signals. The results are discussed in terms of the commonalities shared by perception and imaging as they appear in the Perky effect and cognitive style.     

Validity of rating scales in assessing aggressive behavior in classroom settings

The teachers of 35 boys attending a Lehigh University-based laboratory school for emotionally and behaviorally disturbed children completed rating scales designed to assess aggressive behavior in children. Children also completed similar self-report instruments. Frequency counts of aggressive outbursts and outburst durations were recorded by teachers over a 4-week period. The results of the study found significant correlations among teacher-completed and child-completed measures. The relationships between child-completed measures, one of the teacher measures, and the direct observation measure were not significant. One teacher-completed measure, but no child-completed measures, had significant correlations with aggressive outbursts and durations. The implications for behavioral assessment are discussed.     

Joint Influence of Visual and Auditory Words in the Stroop Task

We conducted four Stroop color–word experiments to examine how multiple stimuli influence interference. Experiments 1a and 1b showed that interference was strong when the word and color were integrated, and that visual and auditory words made independent contributions to interference when these words had different meanings. Experiments 2 and 3 confirmed this pattern when the word information and color information were not integrated, and hence when overall interference was substantially less. Auditory and visual interference effects are comparable except when the visual distracter is integrated with the color, in which case interference is substantially enhanced. Overall, these results are interpreted as being most consistent with a joint influence account of interference as opposed to a capture account.