Repetition in the transcortical aphasias

Transcortical aphasic patients were assessed on a repetition task comprised of both well-formed and deviant sentences. The patients faithfully repeated those sentences that were factually incorrect but grammatically well formed, and those sentences that were ungrammatical because of selection restriction violations. In contrast, presented with sentences featuring only minor syntactic violations (e.g., lack of number agreement), the patients spontaneously, and without awareness, resisted exact repetition; moreover, the resultant changes most often served to correct the syntactic deviations. Repetitions of sentences of this latter type also revealed a difference between the patients as a function of level of comprehension. The transcortical motor aphasic patient was influenced by semantic factors in his alterations of the minor syntactic violations, while the transcortical sensory aphasic was not. These findings are discussed in relation to the notion of autonomous syntactic processing. They are taken to suggest that syntactic facts such as number agreement are represented at a level in the processing chain that is distinct from that of semantic representation.     

The appreciation of antonymic contrasts in aphasia

To secure information on the ability of aphasic patients to comprehend antonymic relations, the kinds of confusions typically made, and the extent to which antonymic sensitivity depends upon mode of presentation and task demands, three linguistic and nonlinguistic tests were administered to aphasic patients, right hemisphere-damaged patients, and non-neurological controls. Although difficulty with antonymous relations was found among all the organic patients, the kinds of problems evidenced and the relative profile of difficulties differed across populations. Among the principal findings were the generally preserved sensitivity to antonymy found among anterior (particularly Broca's) aphasics; a surprising insensitivity to antonymy and a preference for synonyms, found among right hemisphere patients, particularly on the nonlinguistic tasks; a relative preservation of sensitivity to antonymy on nonlinguistic tasks, coupled with a loss of such sensitivity on linguistic tasks, found among posterior (particularly Wernicke's) aphasics; a proclivity toward stereotypical correct responses among the organic patients; and an absolutely worse performance by right hemisphere patients on tasks involving antonymic relations in pictures and abstract designs.     

A study of spelling in aphasia

To secure systematic information on spelling abilities following damage to the dominant hemisphere, a test probing performance in three modalities of response was administered to a group of aphasic patients. Except for a predictable deficit among anterior aphasics in oral spelling, anterior and posterior aphasics exhibited comparable performances on the measures of spelling. However, anterior and posterior aphasics differed from one another on the kinds of words they most accurately spelled, the errors they were prone to make, and certain strategies which they characteristically adopted. These results suggest two alternative approaches to spelling: one approach, common in posterior aphasics, entails choosing letter combinations on the basis of their customary sounds; a second approach, common among anterior aphasics, appears to rely on a partially preserved image of the word's appearance.     

Responding under sequence schedules of electric shock presentation

Lever pressing by squirrel monkeys was examined under second-order schedules of electric shock presentation in which different discriminative stimuli were associated with consecutive components (sequence schedules). Components were always two-minute fixed-interval schedules, and three different overall schedules were studied. Under an overall eight-minute fixed-interval schedule, the first component completion after at least eight minutes had elapsed produced electric shock. The number of components actually completed ranged from one to four; thus, different discriminative stimuli were occasionally associated with electric shock presentation. Under an overall “yoked” variable-ratio schedule, electric shock was presented after completion of a variable number of components; the required number and the distribution of components were matched to those obtained under the overall eight-minute fixed-interval schedule. Under an overall fixed-ratio schedule, electric shock was presented after completion of four components (chained schedule). Under all three sequence schedules, responding in early components was characterized by a pause followed by a single response after the end of the two-minute interval; responding in later components was characterized by a shorter pause followed by positively accelerated responding. Manipulation of overall schedules of shock presentation in these complex behavioral situations produced changes in responding comparable to those ordinarily obtained after similar manipulation of dependencies under both single and second-order schedules of food presentation. These experiments extend the range of conditions and levels of complexity under which responding can be maintained by presentation of electric shock.     

RESPONDING MAINTAINED UNDER INTERMITTENT SCHEDULES OF ELECTRIC-SHOCK PRESENTATION: “SAFETY” OR SCHEDULE EFFCTS?

Four experiments were conducted in which lever pressing by squirrel monkeys was maintained under multiple, mixed, or chained schedules of electric-shock presentation. In the first two experiments, a multiple schedule was employed in which a fixed-interval schedule of shock presentation alternated with a signaled two-minute component. Initially, no events were scheduled during the two-minute component (a safety period). In the first experiment, the safety period was “degraded” by introducing and systematically increasing the frequency of periodic shocks presented during that component. In the second experiment, the proportion of overall safe time to unsafe time was decreased by decreasing the value of the fixed-interval schedule while holding constant shock frequency during the two-minute component. In the third experiment, the overall arrangement was changed from a multiple to a mixed schedule in an attempt to determine whether fixed-interval responding would be maintained when a single exteroceptive stimulus was associated with both components. In the fourth experiment, the overall arrangement was changed from a multiple to a chained schedule in an effort to determine whether fixed-interval responding would be maintained when its consequence was presentation of a signaled “unsafe” period. Fixed-interval responding was well maintained under all experimental conditions; the varied relationships obtained lend more support to conceptualizations of shock-maintained behavior as exemplifying schedule-controlled behavior than to suggestions that such behavior may be readily accounted for by “safety theory.”     

Parameters affecting the maintenance of negatively reinforced key pecking

Three negative reinforcement experiments employing a key-peck response are described. In Experiment I, pigeons shocked on the average of twice per minute (imposed condition) could produce, by pecking a key, an alternate condition with correlated stimuli. Delayed shocks were added, across sessions, to the alternate condition until pecking stopped. Two of three pigeons continued to peck despite a 100% increase in shock frequency. In Experiment II, pigeons were shocked in the imposed condition four times per minute. The postresponse delay to shock was held constant by delivering, in the alternate condition, the next shock, or the next two, three, or four shocks from the imposed-condition shock schedule. All three subjects continued to peck with no change in delay to the first two postresponse shocks but with a 75% reduction in shock frequency. In Experiment III, a response produced an immediate shock followed by a shock-free period. Three of four subjects continued to respond despite reduced delay to shock. Delay-to-shock or shock-frequency reduction was sufficient to maintain key pecking, but neither was necessary. The conditions that negatively reinforce the pigeon's key peck were similar to conditions that negatively reinforce the rat's bar press.     

Brief assessment and treatment of pica using differential reinforcement,response interruption and redirection,and competing stimuli

Pica is a life threating form of challenging behavior displayed by individuals with intellectual and developmental disabilities. In most cases, pica is maintained by automatic reinforcement. Common interventions for pica use some combination of response blocking, response interruption and redirection (RIRD), differential reinforcement of alternative behavior (DRA), and noncontingent reinforcement with competing stimuli. However, there is need for additional research regarding DRA procedures that emphasize skills acquisition by teaching alternative behaviors that modify the established behavioral chain of pica responses that occur in the presence of non-edible stimuli. There is also a need to examine the generality of recent advances in competing stimulus assessment (CSA) methodologies—namely, the augmented-CSA (A-CSA)—to pica. Thus, the purpose of the present investigation was to systematically replicate and extend previous research for the assessment and treatment of pica in an individual with IDD. First, we conducted a functional analysis to identify environmental variables associated with pica. Next, taught Patrick a differential response (i.e., discard pica items in trash receptacle) to earn reinforcers in conjunction with a RIRD procedure. Finally, we conducted an A-CSA for pica. Overall, low rates of pica were maintained over time with a combination of these procedures, and treatment was generalized across settings and people.     

Promoting resilience to depression among couples during pregnancy: The protective functions of intimate relationship satisfaction and self-compassion

Pregnancy, while often marked by joy, may pose considerable risk for depression among parents. Against a backdrop of adverse life events, expectant parents may be even more vulnerable to developing symptoms of depression during the prenatal period. Thus, it is critical to identify sources of resilience that might facilitate a successful transition to parenthood among couples who have a history of adversity. Prior work suggests that interpersonal and intrapersonal factors associated with resilience, such as intimate relationship satisfaction and self-compassion (i.e., self-kindness, common humanity, and mindfulness), have the potential to attenuate prenatal depression among couples with a history of stressful life experiences. We tested this possibility in a sample of 159 couples navigating pregnancy. As predicted, a greater number of prior stressful life experiences was associated with increased depression symptom severity for both mothers and fathers. However, moderation analyses revealed the positive link between cumulative stressful life experiences and depression symptom severity was attenuated among mothers who reported greater self-compassion in the form of feelings of common humanity, and fathers who reported higher levels of intimate relationship satisfaction and self-compassion in the form of mindfulness. Findings suggest enhancing intimate relationship satisfaction and self-compassion among expectant couples may be valuable in attenuating prenatal depression among those with a greater history of adversity.     

The predictive validity of peer assessment in law enforcement: a 6 year follow-up

This study examined the relations between peer assessment and long-term law enforcement/job performance. Sixty-nine law enforcement cadets completed peer rankings of likelihood of success in job performance. These peer rankings were significantly correlated with supervisor ratings, as well as absenteeism and retention, after 1 year of employment. In the present study, both subjective and objective job performance data were collected from a variety of employing job performance agencies after 6 years of employment. Peer rankings were still significantly correlated (r=.40, p<.05) with retention after 6 years, but were not significantly correlated to any job performance index. These results support the potential usefulness of peer assessment data even after several years have passed. © 1998 John Wiley & Sons, Ltd.