Cocaine-induced brainstem seizures and behavior.

A variety of abnormal sensory/motor behaviors associated with electrical discharges recorded from the bilateral brainstem were induced in adult WKY rats by mechanical (electrode implants) and DC electrical current stimulations and by acute and chronic administration of cocaine. The electrode implant implicated one side or the other of the reticular system of the brainstem but subjects were not incapacitated by the stimulations. Cocaine (40 mg/kg) was injected subcutaneously for an acute experiment and subsequent 20 mg/kg doses twice daily for 3 days in a chronic study. Cocaine generated more abnormal behaviors in the brainstem perturbation group, especially the electrically perturbated subjects. The abnormal behaviors were yawning, retrocollis, hyperactivity, hypersensitivity, "beating drum" behavior, squealing, head bobbing, circling, sniffing, abnormal posturing, and facial twitching. Shifts in the power frequency spectra of the discharge patterns were noted between quiet and pacing behavioral states. Hypersensitivity to various auditory, tactile, and visual stimulation was present and shifts in the brainstem ambient power spectral frequency occurred in response to tactile stimulation. These findings suggest that the brainstem generates and propagates pathological discharges that can be elicited by mechanical and DC electrical perturbation. Cocaine was found to activate the discharge system and thus induce abnormal behaviors that are generated at the discharge site and at distant sites to which the discharge propagates. Cognitive functions may also be involved since dopaminergic and serotonergic cellular elements at the brainstem level are also implicated.     

A brainstem “mini-discharge” syndrome (anesthesia dolorosa)

Chronic pain consisting of anesthesia dolorosa secondary to bilateral interruption of the trigeminal nerves is presented as a brain stem reticular denervation syndrome. Electrothalamograms revealed fast frequency discharges in the mesothalamic prerubral and centermedian reticular formation. Mesothalamic electrical stimulation attenuated the discharges. Pain and other symptoms presumably of brainstem origin also were attenuated or abolished by therapeutic electrical stimulation twice daily. It is postulated that brain stem-represented behavioral generators are implicated by the reticular discharges in order to produce the complex symptomatology. Consequently the symptom complex is collectively identified as a brainstem “mini-discharge” syndrome. A theoretical discussion is presented to defend the thesis that reticular denervation-induced low threshold discharge system accounts for the episodic states of pain, dyskinesia, mood, and memory disturbances.     

Shyness, group dependence and self-concept: attributes of the imaginary audience

The imaginary audience of 328 early and late adolescents was studied from the viewpoint of providing educators and clinicians with insight into its attributes--those which both facilitate and hinder youths' development. Early adolescents (about 14 or 15 years of age) displayed a greater awareness of an imaginary audience which probably contributed to their observed, elevated group dependence. Unexpectedly, the shyness of adolescents highly sensitive to an imaginary audience increased with age, possibly because they are unwilling to provide themselves with the social experiences necessary for decentering. Likewise, those highly sensitive to an imaginary audience projected low self-concepts and thus imply that their audience is relatively critical; thus, they probably validate a self-fulfilling prophecy, oblivious to a possible contradictory external reality. The anticipated fact that females appeared to be less socially bold and more group dependent than males might account, in part, for females' greater responsiveness to an imaginary audience. It is suggested that educators and clinicians encourage youth to validate social hypotheses in order to promote the dissolution of the imaginary audience, especially of those who are shy and display self-deprecatory tendencies.     

The use of a resident daily scheduling procedure to increase appropriate social,ward, and scheduling behavior in adult psychiatric residents (patients)

The purpose of the present experiment was to investigate the efficacy of a goal orientation procedure in their treatment of apathy, isolation, and insufficient goal setting skills in chronic psychiatric residents. The experiment was conducted in a behaviorally-oriented deinstitutionalization program in a state psychiatric hospital. Three male and four female chronic psychiatric residents served as research participants. A group repeated measures design with four within-participant phases (ABA‘B’) was utilized. The goal orientation procedure included a written schedule that was completed by each research participant daily. This Daily Living Schedule required that a behavior be specified by the participant for every half-hour period during the day (8:30 a.m. to 9:00 p.m.). During all four phases of the experiment, research participants were observed on the ward from 8:30 a.m. to 12:00 noon and 1:00 p.m. to 5:00 p.m. for engagement in scheduled target behaviors. The daily scheduling procedure produced substantial increases in appropriate behavior such as social activities, ward jobs, and participation in treatment programs, whereas decrease were produced in inappropriate behavior such as isolation and day time sleeping.     

EFFECTS OF REINFORCEMENT HISTORY AND INSTRUCTIONS ON THE PERSISTENCE OF STUDENT ENGAGEMENT

We examined the effects of three reinforcement histories on the persistence of task engagement by 2 fourth-grade students using a partially counterbalanced ABCDBCD design. In each condition, an experimenter made four student contacts during the first 2 min of each session (reinforcement baseline), followed by an 8-min extinction period. The reinforcement history that contained an instructional control component produced the greatest persistence in student engagement. The applied relevance of instructional control is discussed.     

A neurophysiologic model for aggressive behavior in the cat

A neurophysiologic model for aggessive behavior in the cat is proposed. Stimulus-bound and seizure-bound aggression was evaluated in relation to limbic and basal ganglia induced seizures (after-discharges). Electrically induced limbic and basal ganglia afterdischarges were used because they are known to implicate septohypothalamic sites from which aggression can be elicited by direct stimulation. The occurrence of behavioral aggression is correlated with the discharge characteristics of a single discharging system and with two interacting discharging systems. Aggression is composed of autonomic and somato-motor components which poses relatively low and high thresholds, respectively, for their activation. Aggression occurring during a combined septum and amygdala discharge was more intense and prolonged than with a septum discharge alone. Participation of a slow frequency discharging basal ganglia system activated seizurebound aggression in an otherwise nonaggressive limbic seizure. The limbic and basal ganglia stimulations and after-discharges lowered the excitability threshold of the aggression system and made it more vulnerable to being activated by external stimuli, such as visual and auditory stimuli. These observations are reminiscent of patients with aggressive behavior associated with psychomotor seizures.     

Limbic system seizures and aggressive behavior (superkindling effects)

Integrative Psychological and Behavioral Science - This study was done to further analyze the neural mechanisms underlying aggressive behavior associated with psychomotor or temporal lobe seizures....