Transfer of the partial reinforcement extinction effect between escape (shock) and appetitive (food) conditioning

In the first experiment rats were given partial reinforcement or continuous reinforcement in either an escape or an appetitive paradigm. Subsequently, the rats received continuous reinforcement training under motivational conditions opposite those experienced earlier. Finally, responses were extinguished according to the motivational conditions experienced in the second phase. The results indicated that partial reinforcement in the initial phase operated to increase resistance to extinction in the last. In a second experiment this intermotivational partial reinforcement extinction effect was shown to survive interpolated experiences with extinction, a 1-week rest period, and continuous reinforcement reacquisition. A third experiment examined the influence of intramodal versus intermodal nonreinforcement-reinforcement sequences on the intermotivational partial reinforcement extinction effect. Interactive effects between similarity of aversive outcome (escape nonreinforcement, appetitive nonreinforcement) and reinforcement type (negative, positive) were found. The theoretical implications of the data from all three experiments are discussed.     

Visual search for change in older adults

Previous research has demonstrated that younger adults are surprisingly poor at detecting substantial changes to visual scenes. Little is known, however, about age differences in this phenomenon. In the 2 experiments reported here, older adults were slower than younger adults in detecting changes to simple visual stimuli. This age difference was beyond what would be expected given known age-related changes in processing speed. Examination of eye movement behavior during the search for change suggested that age-related changes in the useful field of view and degree of cautiousness play a significant role. Speed of processing and 3 age-related eye movement behaviors explained 85% of the variance in change detection latency, eliminating the effect of age.     

Family connections: a program for relatives of persons with borderline personality disorder

This study assessed changes in family members who participated in Family Connections, a 12-week manualized education program for relatives of persons with borderline personality disorder (BPD). Family Connections, led by trained family members, is based on the strategies of standard Dialectical Behavior Therapy (DBT) and DBT for families. The program provides (a) current information and research on BPD, (b) coping skills, (c) family skills, and (d) opportunities to build a support network for family members. Forty-four participants representing 34 families completed the pre-, post-, and 6-month postbaseline self-report questionnaires. Analyses employing hierarchical linear modeling strategies showed significant reductions in grief and burden, and a significant increase in mastery from pre- to post-group assessment. Changes were maintained at 6 months post baseline.     

Sweep-induced acceleration in loudness change and the "bias for rising intensities"

A pure tone changing continuously in intensity shows sweep-induced fading (SIF) of loudness as intensity sweeps down and may show a lesser degree of sweep-induced enhancement (SIE) as intensity sweeps up (Canévet & Scharf, 1990); the former effect has been called decruitment, the latter upcruitment. An opposite effect-upsweeps being judged to show more loudness change than downsweeps--has been reported by Neuhoff (1998). These disparate results might stem from several procedural differences. We found that differences in the sweep's duration and intensity level did not account for the disparity, nor did the presence of a steady tone preceding the sweep. In a second experiment, direct judgments of sweep size, such as those Neuhoff's (1998) listeners made, were affected not only by sweep size itself, but also by the intensity at the end of the sweep. The latter effect was especially marked for upsweeps. Neuhoffs (1998) proposed "bias for rising intensities" was found only with a method for judging sweep size that is more sensitive to end level than to sweep size.     

Symptoms of depression in older home-care patients: patient and informant reports

The purpose of this study was to examine the level of agreement and patterns of disagreement between home-care patient and informant reports of depressive symptoms. The authors interviewed a sample of 355 older home-care patients and their informants using the Structured Diagnostic Interview for DSM-IV (R. L. Spitzer, M. Gibbon, & J. B. Williams, 1995). Informants reported more psychological symptoms than patients, and this type of discrepancy was higher for patients with cognitive impairment and patients who had younger informants. Younger informants also reported more cognitive symptoms, whereas patients were more likely to report suicidal thoughts or ideation if they were not cognitively impaired. The patterns of these discrepancies may reflect age- and cohort-related response bias in the reports of depressive symptoms obtained from older adults.     

Hippocampal inactivation enhances taste learning

Learning tasks are typically thought to be either hippocampal-dependent (impaired by hippocampal lesions) or hippocampal-independent (indifferent to hippocampal lesions). Here, we show that conditioned taste aversion (CTA) learning fits into neither of these categories. Rats were trained to avoid two taste stimuli, one novel and one familiar. Muscimol infused through surgically implanted intracranial cannulae temporarily inactivated the dorsal hippocampus during familiarization, subsequent CTA training, or both. As shown previously, hippocampal inactivation during familiarization enhanced the effect of that familiarization on learning (i.e., hippocampal inactivation enhanced latent inhibition of CTA); more novel and surprising, however, was the finding that hippocampal inactivation during training sessions strongly enhanced CTA learning itself. These phenomena were not caused by specific aspects of our infusion technique--muscimol infusions into the hippocampus during familiarization sessions did not cause CTAs, muscimol infusions into gustatory cortex caused the expected attenuation of CTA, and hippocampal inactivation caused the expected attenuation of spatial learning. Thus, we suggest that hippocampal memory processes interfere with the specific learning mechanisms underlying CTA, and more generally that multiple memory systems do not operate independently.     

Neuroethics: the practical and the philosophical

In comparison with the ethical issues surrounding molecular genetics, there has been little public awareness of the ethical implications of neuroscience. Yet recent progress in cognitive neuroscience raises a host of ethical issues of at least comparable importance. Some are of a practical nature, concerning the applications of neurotechnology and their likely implications for individuals and society. Others are more philosophical, concerning the way we think about ourselves as persons, moral agents and spiritual beings. This article reviews key examples of each type of issue, including the relevant advances in science and technology and their accompanying social and philosophical problems.     

For Shame! The Effect of Community Cooperative Context on the Probability of Voting

The question of why some people vote in American national elections and others do not has been the focus of a vast literature in social science. This study builds on previous work emphasizing the political relevance of civic norms prescribing social cooperation. County-level census response rates were used to measure the strength of civic norms in counties represented in the 1992 National Election Study (NES). The analysis shows that a person's likelihood of voting increases with the census response rate in the county of residence, controlling for the usual set of factors associated with turnout. The probability of voting was also correlated with the incidence of cooperative behavior in other arenas, such as giving to charities or willingly serving on juries. These findings provide support for the importance of cooperative norms in explaining political participation. In addition, the relationship between voting and county-level census response was significantly greater among respondents who read newspapers more often; hence, newspapers evidently are one means by which social expectations are communicated.