Dissociation of data-based and expectancy-based memory following hippocampal lesions in rats

Sham-operated and nonoperated animals or animals with hippocampal lesions were presented with sets of trials to test both expectancy-based and data-based memory within the same task. During the study phase of each trial the animals were presented with a constant sequence of five arms on an eight-arm radial maze followed by a test phase in which a recognition test requiring a win-stay rule was used. Expectancy-based memory was measured during the study phase of the trials as a pattern of correct or incorrect orienting responses in anticipation of the ensuing doors in the constant sequence. Both groups of animals acquired correct orienting responses at the same rate, emitted the same pattern of correct orienting responses, and made the same number and pattern of intralist and extralist intrusion errors. Data-based memory was measured during the test phase of the trial as correct recognition test performance. During the test phase the animals with hippocampal lesions were impaired relative to controls on both immediate and 24-h recognition tests. These results suggest that the hippocampus might mediate only data-based, but not expectancy-based, memory and imply a possible dissociation between expectancy-based and data-based memory systems.     

Aging and the discrimination of 3-D shape from motion and binocular disparity

Two experiments evaluated the ability of younger and older adults to visually discriminate 3-D shape as a function of surface coherence. The coherence was manipulated by embedding the 3-D surfaces in volumetric noise (e.g., for a 55?% coherent surface, 55?% of the stimulus points fell on a 3-D surface, while 45?% of the points occupied random locations within the same volume of space). The 3-D surfaces were defined by static binocular disparity, dynamic binocular disparity, and motion. The results of both experiments demonstrated significant effects of age: Older adults required more coherence (tolerated volumetric noise less) for reliable shape discrimination than did younger adults. Motion-defined and static-binocular-disparity-defined surfaces resulted in similar coherence thresholds. However, performance for dynamic-binocular-disparity-defined surfaces was superior (i.e., the observers?? surface coherence thresholds were lowest for these stimuli). The results of both experiments showed that younger and older adults possess considerable tolerance to the disrupting effects of volumetric noise; the observers could reliably discriminate 3-D surface shape even when 45?% of the stimulus points (or more) constituted noise.     

Clamped Corticosterone (B) Reveals the Effect of Endogenous B on Both Facilitated Responsivity to Acute Restraint and Metabolic Responses to Chronic Stress

To determine the effects of both corticosterone (B) and chronic stressors on acute ACTH responses to restraint, young male rats were exposed to streptozotocin-induced diabetes, cold (5-7 degreesC) or intracerebroventricular (icv) neuropeptide Y (NPY) for 5 d and then exposed to restraint within 2 h after lights on. Two groups of rats were studied: intact and adrenalectomized replaced with B pellets that maintained plasma B in the normal mean 24-h range of intact rats. In addition to ACTH and B responses to restraint on d 5, body weight, food intake, fat depots, glucose and other hormones were measured to determine the role of stress-induced elevations in B on energy balance. ACTH responses to restraint were normal in intact rats subjected to diabetes or cold. By contrast, there was no ACTH or B response to restraint in NPY-infused intact rats. All 3 groups of chronically stimulated adrenalectomized rats with clamped B had facilitated ACTH responses to restraint compared to their treatment controls. Overall food intake increased in all groups of stressed rats; however, augmented intake occurred only during the light in intact rats and equally in the light and dark in B-clamped rats. White adipose depot weights were decreased by both diabetes and cold and increased by NPY in intact rats; the decreases with cold and increases with NPY were both blunted and changes in fat stores were not significant in adrenalectomized, B-clamped rats. We conclude that: 1. diabetes- and cold-induced facilitation of restraint-induced afferent input to hypothalamic control of the hypothalamo-pituitary-adrenal (HPA) axis is opposed in intact rats by the elevated feedback signal of B secretion; 2. NPY does not induce facilitation of afferent stress pathways; 3. chronic stimulation of the HPA axis induces acute hyperresponsiveness of hypothalamic neurons to restraint provided that the afferent input of this acute stimulus is not prevented by B feedback; 4. stimulus-induced elevations in B secretion result in day-time feeding; 5. insensitivity of both caloric efficiency and white fat stores to chronic stress in adrenalectomized, B-clamped rats results from loss of normally variable B levels.     

Focused videotape feedback psychotherapy: An integrated treatment for emotionally and behaviorally disturbed children

This controlled study describes the development and therapeutic effectiveness of Focused Videotape Feedback Psychotherapy. FVFP integrates parent-training, family therapy, and psychodynamically-oriented therapy as a treatment for children with emotional and behavioral disorders. Of the 105 children and their families, ages 4-10 years, referred for the study, only 40 met the strict diagnostic, research, and randomisation criteria for inclusion in one of the three research groups: FVFP, Psychodynamically-oriented, or Control. Evaluation was at pretreatment, 8 weeks, 16 weeks, and 20th week follow-up. Both treatment procedures were effective. FVFP produced more positive behavioral and affective changes at follow-up and was more time and cost effective.     

Allocation of cognitive processing capacity during human autonomic classical conditioning

In each of two experiments, allocation of cognitive processing capacity was measured in college-student subjects during autonomic discrimination classical conditioning. A 7.0-sec delay paradigm was used to establish classically conditioned responses to a reinforced visual conditioned stimulus (CS+). Electrodermal responses were the primary measures of autonomic classical conditioning. Allocation of processing capacity was measured by monitoring performance on a secondary reaction-time (RT) task. The auditory secondary-task RT signal was presented before, and 300, 500, 3500, 6500, and 7500 msec following CS onset. The RT signal was also presented following properly and improperly cued shock unconditioned stimuli (UCSs). Significant discrimination classical conditioning was obtained in both experiments. Comparison with control subjects who did not receive the RT signals indicated that the presence of the RT signals did not interfere with the development of classical conditioning. Four principal findings were obtained with the secondary-task RT measure. First, RTs to signals presented during CS+ were consistently slower than RTs to signals presented during CS-. This finding indicates that greater capacity allocation occurred during CS+ than CS- and is consistent with recent cognitive interpretations of classical conditioning. Second, the largest capacity allocation (i.e., slowing of RTs) occurred 300 msec following CS+ onset. This finding is consistent with the notion that subjects are actively processing the signal properties of the CS+ at 300 msec following CS+ onset. Third, presentation of the UCS when improperly cued (following CS-) significantly increased capacity allocation, whereas presentation of the same UCS when properly cued (following CS+) did not affect capacity allocation. These findings indicate that subjects were actively prepared for the UCS following CS+ but not following CS- and that a surprising UCS elicits greater capacity allocation than does an expected UCS. Fourth, large electrodermal responders to the CSs exhibited patterns of capacity allocation during the CSs, particularly during the CS+, different from those of small electrodermal responders. In particular, they exhibited significantly longer RTs at 300 msec after CS+ onset than did the small responders, followed by a shortening of RT at 500 msec relative to the small responders. This finding suggests that large electrodermal responders devote greater processing capacity to significant environmental stimuli than do small responders and that their processing may begin and be completed more rapidly. All in all, the data indicate the complexity of the cognitive processes that occur during human classical conditioning and the usefulness of the secondary-task technique in integrating conditioning theories and psychophysiology with cognitive psychology.     

Further evidence of a robust point-of-view bias in videotaped confessions

Four experiments were conducted to test possible limits on the previously demonstrated point-of-view bias in videotaped confessions. Study 1 showed that deliberation did not eliminate the bias. Study 2 showed that forewarning did not eliminate the bias. Study 3 showed that directing greater attention to the content of the confession did not eliminate the bias. Study 4 showed that using a lengthier, case-based confession also did not eliminate the bias. Taken together, this research clearly indicates that the legal system needs to be concerned with the potential for bias that exists in videotaped confessions. This research was supported by funds from the Ohio Board of Regents and the National Science Foundation (BNS-8911067 and SBR-9514966). We thank Kevin Apple, Kim Dudley, Kelly Kinnison, Melanie LaForce, Matthew Leafgren, Richelle Newvahner, Laurie Olsen, John Ray, Alicia Santuzzi, Jason Secondi, and Katie Strieker for their contributions to various aspects of the research. With the exception of Lassiter, order of authorship is alphabetical.     

Emotion regulation abilities and the quality of social interaction

Emotion regulation abilities, measured on a test of emotional intelligence, were related to several indicators of the quality of individuals' social interactions with peers. In a sample of 76 college students, emotion regulation abilities were associated with both self-reports and peer nominations of interpersonal sensitivity and prosocial tendencies, the proportion of positive vs. negative peer nominations, and reciprocal friendship nominations. These relationships remained statistically significant after controlling for the Big Five personality traits as well as verbal and fluid intelligence.     

Dynamic Social Networks in Recovery Homes

Acute treatment aftercare in the form of sober living environments—i.e., recovery houses—provide an inexpensive and effective medium-term treatment alternative for many with substance use disorders. Limited evidence suggests that house-situated social relationships and associated social support are critical determinants of how successful these residential experiences are for their members, but little is known about the mechanisms underlying these relationships. This study explored the feasibility of using dynamic social network modeling to understand house-situated longitudinal associations among individual Alcoholics Anonymous related recovery behaviors, length of residence, dyadic interpersonal trust, and dyadic confidant relationship formation processes. Trust and confidant relationships were measured 3 months apart in U.S. urban-area recovery houses, all of which were part of a network of substance use recovery homes. A stochastic actor-based model was successfully estimated from this data set. Results suggest that confidant relationships are predicted by trust, while trust is affected by recovery behaviors and length of residence. Conceptualizing recovery houses as a set of independent, evolving social networks that can be modeled jointly appears to be a promising direction for research.     

Sad and happy emotion discrimination in music by children with cochlear implants

Children using cochlear implants (CIs) develop speech perception but have difficulty perceiving complex acoustic signals. Mode and tempo are the two components used to recognize emotion in music. Based on CI limitations, we hypothesized children using CIs would have impaired perception of mode cues relative to their normal hearing peers and would rely more heavily on tempo cues to distinguish happy from sad music. Study participants were children with 13 right CIs and 3 left CIs (M = 12.7, SD = 2.6 years) and 16 normal hearing peers. Participants judged 96 brief piano excerpts from the classical genre as happy or sad in a forced-choice task. Music was randomly presented with alterations of transposed mode, tempo, or both. When music was presented in original form, children using CIs discriminated between happy and sad music with accuracy well above chance levels (87.5%) but significantly below those with normal hearing (98%). The CI group primarily used tempo cues, whereas normal hearing children relied more on mode cues. Transposing both mode and tempo cues in the same musical excerpt obliterated cues to emotion for both groups. Children using CIs showed significantly slower response times across all conditions. Children using CIs use tempo cues to discriminate happy versus sad music reflecting a very different hearing strategy than their normal hearing peers. Slower reaction times by children using CIs indicate that they found the task more difficult and support the possibility that they require different strategies to process emotion in music than normal.     

Stereoscopic shape discrimination is well preserved across changes in object size

A single experiment evaluated human observers’ ability to discriminate the shape of solid objects that varied in size and orientation in depth. The object shapes were defined by binocular disparity, Lambertian shading, and texture. The object surfaces were smoothly curved and had naturalistic shapes, resembling those of water-smoothed granite rocks. On any given trial, two objects were presented that were either the same or different in terms of shape. When the “same” objects were presented, they differed in their orientation in depth by 25°, 45°, or 65°. The observers were required to judge whether any given pair of objects was the “same” or “different” in terms of shape. The size of the objects was also varied by amounts up to ±40% relative to the standard size. The observers’ shape discrimination performance was strongly affected by the magnitude of the orientation changes in depth - thus, their performance was viewpoint dependent. In contrast, the observers’ shape discrimination abilities were only slightly affected by changes in the overall size of the objects. It appears that human observers can recognize the three-dimensional shape of objects in a manner that is relatively independent of size.