Comparison of Single Unit Responses to Tone, Light, and Compound Conditioned Stimuli during Rabbit Classical Eyeblink Conditioning

Unit recordings and lesion studies have implicated the cerebellum as an essential site for the acquisition and maintenance of the conditioned eyeblink response. The current study looked at the neural characteristics of conditioned stimulus (CS) processing in the interpositus nucleus of the cerebellum after training New Zealand white rabbits (Oryctolagus cuniculus) in one of two conditioning paradigms: (a) compound conditioning (CMP), a compound CS consisting of light and tone paired with an air puff unconditioned stimulus (US); or (b) stimulus compounding (ALT), alternating blocks of tone CS and light CS trials paired with the air puff US. Single unit responses were recorded during five sessions after the animals had reached an asymptotic level of responding. Animals were tested for behavioral and neural responses to CS alone trials that included tone alone, light alone, and compound tone-light trials. For the CMP group, the compound CS elicited 80 to 90% conditioned eyeblink responses (CRs), whereas the individual tone and light CSs elicited only 40 to 50% CRs. For the ALT group, all three CSs (tone, light, and compound) elicited very high levels of responding of at least 80% CRs. For the CMP group, there were roughly equal numbers of cells responding to all of the CSs. This includes cells that responded exclusively to one, and only one, of the three stimuli and also those cells that responded to combinations of two or more. Cells from the ALT group were far more likely to respond exclusively to only one of the CSs. Both the behavioral and physiological results suggest that the compound tone-light stimulus was processed as a distinct stimulus, separate from the component tone and light. These results are discussed in the context of multisensory processing.     

The Wind Chilled the Spectators, but the Wine Just Chilled: Sense, Structure, and Sentence Comprehension

Anticipation plays a role in language comprehension. In this article, we explore the extent to which verb sense influences expectations about upcoming structure. We focus on change of state verbs like shatter , which have different senses that are expressed in either transitive or intransitive structures, depending on the sense that is used. In two experiments we influence the interpretation of verb sense by manipulating the thematic fit of the grammatical subject as cause or affected entity for the verb, and test whether readers' expectations for a transitive or intransitive structure change as a result. This sense-biasing context influenced reading times in the postverbal regions. Reading times for transitive sentences were faster following good-cause than good-theme subjects, but the opposite pattern was found for intransitive sentences. We conclude that readers use sense-contingent subcategorization preferences during on-line comprehension.     

Juvenile sex offenders: similar to, or different from, other incarcerated delinquent offenders?

The purpose of the present study was to compare incarcerated juvenile sex offenders to incarcerated youth who committed confrontational but nonsex offenses, and to those youth who committed only nonconfrontational, nonsex offenses. Furthermore, comparisons were made between two subtypes of sex offenders: those youth convicted for rape or sodomy vs those convicted for child molestation. Eighty-three male juvenile delinquents served as participants. Teachers within the correctional facility completed an instrument which allowed the examination of the two areas of interest: externalizing problems and internalizing problems. The results indicated that sex offenders generally, and particularly those who had committed only sex offenses, were perceived as having fewer externalizing and internalizing problems. No differences emerged between the two subtypes of sex offenders. Implications, as well as limitations, of the findings are discussed.     

Tolerance of ambiguity: A review of the concept, its measurement and applications

This paper reviews the scattered and diffuse literature on the tolerance of ambiguity construct (AT). The work by Frenkel-Brunswik (1948) is considered in some detail to help explain the origin of the concept as well as its diffusion to many areas of psychology. Second, thirty years of correlational research, which looks at the studies correlating AT measures with a variety of psychological variables, are reviewed. Third, evidence for the differential distribution of AT among particular groups is reviewed. Fourth, the psychometric properties of the various self-report AT measures are considered in some detail. The two final sections look at organizational and cultural correlates of AT (the areas currently most interested in the AT concept). The conclusion attempts to explain varying patterns of interest in the AT construct and its current status.     

Factors associated with respite care use by families with a child with disabilities

This paper reviews the literature on respite care utilization, describes a respite care program in Arkansas, and reports on a study of utilization initiated by the Arkansas Division of Mental Health Services (DMHS). Among the 89 families qualifying for respite services, 70 consented to participate, and 66 were surveyed in a phone interview. Users (n=54) and non-users (n=12) were compared relative to a variety of staff, child, geographic, and budget differences. Also, respite use was examined relative, to the aforementioned variables based on level of use, (i.e., none, low, moderate, high). There were no differences in use according to age, the number of family members, family income, or needs of the child. A larger percentage of non-use and low use of respite care was evident among those families receiving Tax Equity Fiscal Responsibility Act (TEFRA) benefits. There were no significant differences between races related to perceived barriers to care. Differences in expectations/experiences with respite care among rural and urban groups were limited with rural respondents expressing, concern about travel/distance issues. Overall, the program as a whole received positive ratings by parents, and no clear factors were found to be related to non-use in the small sample (n=12) who did not take advantage of respite services.     

Speed of Lexical Activation in Nonfluent Broca''s Aphasia and Fluent Wernicke''s Aphasia

Rapid, automatic access to lexical/semantic knowledge is critical in supporting the tight temporal constraints of on-line sentence comprehension. Based on findings of “abnormal” lexical priming in nonfluent aphasics, the question of disrupted automatic lexical activation has been the focus of many recent efforts to understand their impaired sentence comprehension capabilities. The picture that emerges from this literature is, however, unclear. Nonfluent Broca's aphasic patients showinconsistent,notabsent,lexical priming, and there is little consensus about the conditions under which they do and do not prime. The most parsimonious explanation for the variable findings from priming studies to date is that the primary disturbance in Broca's lexical activation has something to do withspeedof activation. Broca's aphasic patients prime when sufficient time is allowed for activation to spread among associates. To examine this “slowed activation” hypothesis, the time course of lexical activation was examined using a list priming paradigm. Temporal delays between successive words ranged from 300 to 2100 msec. One nonfluent Broca's aphasic patient and one fluent Wernicke's patient were tested. Both patients displayed abnormal priming patterns, though of different sorts. In contrast to elderly subjects, who prime at relatively short interstimulus intervals (ISIs) beginning at 500 msec, the Broca's aphasic subject showed reliable automatic priming but only at a long ISI of 1500 msec. That is, this subject retained the ability to access lexical information automatically if allowed sufficient time to do so, a finding that may help explain disrupted comprehension of normally rapid conversational speech. The Wernicke's aphasic subject, in contrast, showed normally rapid initial activation but continued to show priming over an abnormally long range of delays, from 300 msec through 1100 msec. This protracted priming suggests failure to dampen activation and might explain the semantic confusion exhibited by fluent Wernicke's patients.     

Toys,spatial ability,and science and mathematics achievement: Are they related?

This review of research examines the possible relationships among children's toy playing habits, spatial abilities, and their science and mathematics achievements. Only studies that made use of United States subjects, aged 3- through 13-years-old, are included in the review. Toy playing habits, spatial ability, and science and mathematical achievement appear sex typed. Males and/or children who maintain a masculine sex role orientation tend to play with a wider variety of toys, exhibit superior spatial skills, and maintain greater science and mathematics achievement scores than females and/or children with feminine sex role orientations.     

Anger control in response to verbal provocation: Effects of stimulant medication for boys with ADHD

Although stimulant medication reduces hyperactive children's aggression in naturalistic settings, stimulant effects on anger control have not been demonstrated. We therefore assessed the role of methylphenidate in enhancing response to verbal provocation from familiar peers and from role-playing adults. Twenty-four boys with attention deficithyperactivity disorder (ADHD), aged 6–12, received small-group cognitivebehavioral intervention in anger management skills. During posttraining assessments, the children were randomly assigned to placebo versus. 6 mg/kg of methylphenidate. In the peer provocations, methylphenidate enhanced self-control, decreased physical retaliation, and marginally increased the display of coping strategies. Medication and prompting were minimally beneficial in the delayed, adult-administered generalization assessments. Among the issues discussed are (a) differences between peer and adult provocation and (b) the roles of medication dosage and multimodality intervention for promoting socially competent behavior in children with ADHD.We gratefully acknowledge the Fernald Child Study Center of the University of California, Los Angeles, which provided major support for this research. In addition, we acknowledge the dedication of the small-group trainers, too numerous to mention individually, who led the intervention procedures for the children, and the experimenters who performed the individual provocation assessments. The careful behavior observations of Linda Douglas, Rebecca Eiser, Deborah Gibson, Mike Glenn, Melissa Michaelson, Jon Rafuse, Fauzia Simjee, Leslie Sherman, and Madelin Tundidor were central to the study. Finally, our colleagues Barbara Henker and Carol K. Whalen were instrumental in facilitating all aspects of this investigation.