Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): III. Contact calls

We trained budgerigars by operant conditioning to discriminate among a set of contact calls in a same-different task and analyzed response latencies from this task by using multidimensional-scaling (MDS) and cluster-analysis procedures. Humans listened to the same calls and indicated the similarity between pairs of calls by a direct rating procedure. An MDS program (sindscal) was used to arrange these complex acoustic stimuli in multidimensional space reflecting perceptual organization. Multiple regression techniques were used to identify the acoustic characteristics of contact calls that were correlated with the perceptual dimensions obtained from MDS. A number of spectral characteristics (e.g., peak frequency, rate of frequency modulation, and concentration of spectral energy) emerged as important for both budgerigars and humans, but the relative salience of these cues differed for the two species. Additional tests with two groups of budgerigars--cagemates and noncagemates--showed that experience with calls can change the salience of various acoustic characteristics used for perceptual organization and individual recognition.     

Coping with victimization: The impact of rape on female survivors,male significant others,and parents

This paper reports on an unusual study of survivors of rape and the effects on the victim, her significant male other person, and her parents. All survivors were victims of the same rapist and were interviewed from 21 months to ten years after the event. The study indicates that the long-term effects of rape may be more significant than previous researchers and practitioners thought was the case. Recommendations are given for more effective help for survivors and those close to them.This study was funded by the Ohio Department of Mental Health, Office of Program Evaluation and Research, Columbus, Ohio, 1985.     

Expert knowledge as mnemonic cues

It is proposed that expert knowledge can operate as a cognitive cueing structure for the acquisition and retention of new information in memory. Two experiments are reported which demonstrate that expert knowledge about football and clothing can act as mnemonic cues for the recall of information newly associated with that knowledge. In Experiment 1 expert terms from the domains of football and clothing and those neutral nouns paired with them were both better recalled by experts than by non-experts. In Experiment 2 passages containing information contrary to factual knowledge about football and clothing were recalled better by experts than by non-experts, in spite of the fact that information in the passages contradicted what the experts already knew. The results of the two experiments were interpreted as showing that expert knowledge provides mental cues that have desirable mnemonic properties such as constructibility, associability, discriminability and invertibility. Also, the interpretation of expert knowledge as a cognitive cueing structure is compared to Ausubel's ideas regarding advance organizers.     

UCLA's Career Counseling Center: A Dialogue About a Unique Service

In this interview, two counseling psychologists describe aspects of a relatively unique career counseling service that has been validated by 40 years of success in the marketplace. Composed of 3 intensive individual interviews and 15 to 25 hours of educational and psychological testing, the service assists clients in identifying and beginning pursuit of suitable educational and occupational goals. The counselors describe how they organize and sift through test results to formulate recommendations for a client's unique career circumstances, why they accept responsibility for developing and presenting concrete recommendations, and what the changes in their clients' concerns suggest about the evolution of work in the United States. Their specificity and professionalism will help counselors understand the craft of career counseling.     

The concepts of depression,anxiety, and neuroticism in questionnaires

In this study, the relations among depression, anxiety, and neuroticism measured by self-report questionnaires were investigated. Subjects were 207 psychiatric patients. High correlations were found among self-report scales purporting to measure depression, anxiety, and neuroticism. Results of a content analysis showed considerable overlap among these scales. A division of items into six content categories did not result in lower correlations compared to the original scales.     

Failure of acute and chronic administration of Δ9-tetrahydrocannabinol to affect the repeated acquisition of serial position responses in pigeons

Pigeons were trained to acquire a new four-response position sequence each day by pecking three response keys in a predetermined order. The key color varied after each correct response prior to food delivery. Acute administration of Γ⁹-tetrahydrocannabinol (Δ⁹-THC) up to a dose that completely eliminated responding, had no effect on total acquisition errors, or on within session patterns of error elimination. Chronic administration of Δ⁹-THC (3–10 mg/kg/day), either before or after the session for 4–7 weeks, also did not affect these error measures, although rates of responding were markedly suppressed and at times no responding occurred Discontinuation of Δ⁹-THC administration for periods of 4–6 weeks also was without effect on errors. These experiments suggest that neither acute nor chronic Δ⁹-THC produce specific effects on the repeated acquisition of serial position responses in pigeons.     

Long latency auditory evoked potentials

Experiment 1 elicited the P1, N1, P2, and N2 components of the long latency auditory evoked potential (AEP) using a 1000 Hz tone presented at 30, 50, or 70 dB SPL and 1-, 3-, or 5- second inter-stimulus intervals to assess the relative effects of the combination of these variables on component amplitude and latency. Four blocks of 16 tone presentations each were recorded from each subject to determine if changes in the AEP would occur because of short-term habituation. Both stimulus factors interacted significantly in a systematic fashion for the amplitude measures, with increases in latency also associated with increases in intensity and inter-stimulus interval. Only minor changes across the four trial blocks for either the amplitude or latency measures were observed over the various stimulus presentation conditions. Experiment 2 employed the same tone stimulus presented at 50 dB SPL and a 3-second inter-stimulus interval. Eight blocks of 64 trials were recorded from each subject on each day for four days to investigate long-term habituation effects. No substantial changes in any of the component amplitudes or latencies were obtained across the 32 trial blocks. It was concluded that intensity and inter-stimulus interval interact to determine AEP amplitude as well as latency values and that the constituent components do not change appreciably with repeated stimulus presentations, even after several days.