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PubMed2006

Sexual dimorphism of neuroglial relationships in the frontal fields of the human brain.

Cytoglioarchitectonic and quantitative methods were used to study the characteristics of neuroglial relationships in fields in the frontal areas of the male and female brains. Series of frontal paraffin sections of thickness 20 microm stained by the Nissl method were used to study fields 8, 12, 47, and 10. In layers III and V of the right and left hemispheres, the densities of pyramidal neurons (N), satellite gliocytes (SG), and N surrounded by SG (SN) per 0.001 mm3, and the SN/N ratio (%) were useful measures of the functional-metabolic activity of the brain. In women, SG, SN, and SN/N were higher in fields 12, 47, and 10 than in men, but were lower in field 8. It is suggested that cortical N have greater metabolic activity in women in emotional-volitional and "intellectual" structures, while men have more N in the motor areas.

Adult↗
PubMed2004

Pediatric asthma: a look at adherence from the patient and family perspective.

Although extensive research has been done in an effort to understand and promote adherence in pediatric asthma, little progress has been made in reducing the prevalence of nonadherence. Some researchers argue that a paradigm shift is necessary to advance the adherence field. Despite the recent trend for increasing the role of families in determining treatment plans, a patient-centered approach has been lacking in adherence to a daily regimen. It is clear that, although patients and families show evidence of inadvertent nonadherence (eg, forgetfulness), they also engage in volitional or intentional nonadherence, via reasoned and purposeful decisions. Patients conduct "experiments" with their regimen components in an effort to balance the burden of disease with the burden of treatment. These experiments typically involve some degree of nonadherence. Perhaps, if researchers strive to better understand the decision-making process involved in these experiments, health care providers can guide families in making adherence decisions that would lead to attainment of treatment goals, improvement in quality of life, and realization of positive clinical outcomes.

Adult↗
PubMed2006

Demyelinating disorders: update on transverse myelitis.

Transverse myelitis (TM) is a focal inflammatory disorder of the spinal cord. Perivascular monocytic and lymphocytic infiltration, demyelination, and axonal injury are prominent histopathogic features of TM. The clinical manifestations of TM are consequent to dysfunction of motor, sensory, and autonomic pathways. At peak deficit, 50% of patients with TM are completely paraplegic (with no volitional movements of legs), virtually all have some degree of bladder dysfunction, and 80% to 94% have numbness, paresthesias, or band-like dysesthesias. Longitudinal case series of TM reveal that approximately one third of patients recover with little to no sequelae, one third are left with a moderate degree of permanent disability, and one third have severe disability. Recent studies have shown that the cytokine interleukin-6 may be a useful biomarker, as the levels of interleukin-6 in the cerebrospinal fluid of acute TM patients strongly correlate with and are highly predictive of disability. Clinical trials testing the efficacy of promising axonoprotective agents in combination with intravenous steroids in the treatment of TM are currently underway.

Biomarkers↗
PubMed1992

Physiologic responses to recumbent versus upright cycle ergometry, and implications for exercise prescription in patients with coronary artery disease.

To clarify the influence of body position on exercise prescription, 14 men (mean age +/- standard deviation 60.0 +/- 6.1 years) with coronary artery disease who underwent randomized recumbent and upright cycle ergometer tests to volitional fatigue were studied. At 100 watts, heart rate (HR), systolic blood pressure, oxygen consumption (VO2), rate pressure product and rating of perceived exertion were greater (p less than 0.05) in the upright than in the recumbent position. At peak exercise, however, these variables were not significantly different. Regressions of relative HR versus VO2 for recumbent and upright cycle ergometry were comparable: y = 1.24x - 32.7 and y = 1.26x - 31.5, respectively, where y = % maximal VO2, and x = % maximal HR. These findings indicate that recumbent exercise prescriptions may be based on the peak HR and VO2 values obtained during upright cycle ergometry, and vice versa. However, differences in the cardiorespiratory responses at submaximal exercise preclude the interchangeability of upright and recumbent training work rates.

Aged↗
PubMed1993

Cough in spinal cord injured patients: comparison of three methods to produce cough.

Pulmonary complications are the major causes of morbidity and mortality for persons with cervical spinal cord injury. Diminished ability to cough constitutes a major contribution to the high incidence of pulmonary morbidity in this population. This article reports preliminary results for a new technique for providing assisted cough in this population. In this study, efficacy of cough (as measured by peak expiratory flow rate) was measured under three conditions: volitionally with no assistance, with manual assist of a therapist, and with electrical stimulation of abdominal muscles. Coughs produced by electrical stimulation were approximately as effective as manually assisted coughs. The results suggest this technique is worthy of more detailed study and may be a potentially effective new modality for assisting spinal cord injured persons to clear their airways.

Abdominal Muscles↗
PubMed1994

Reliability of the maximal aerobic power and ventilatory threshold in adults with cerebral palsy.

This study examines the test-retest reliability of the ventilatory threshold (VT) and the maximum oxygen uptake (VO2max) in adults with cerebral palsy (CP). Nine subjects completed two continuous incremental tests on either a wheelchair ergometer (WE, n = 5) or a cycle ergometer (CE, n = 4) to volitional fatigue. Metabolic and cardiorespiratory responses were continuously monitored during the tests with an automated metabolic cart interfaced with an electrocardiogram. Two experienced evaluators identified the VT using standardized respiratory gas exchange criteria. The reliability coefficient for the VO2max during the two trials was significant (r = 0.83, p < .05). However, there was no significant relationship (p > .05) between the two trials for the oxygen uptake (VO2) at the VT identified by the two evaluators (r = 0.45 and 0.43). The correlations for this variable between the two evaluators were highly significant on each trial (r = 0.99 and 1.00, p < .01). No significant differences were observed between the two trials for the VO2 at the VT and the VO2max. These results suggest that when monitoring the cardiorespiratory fitness of adults with CP, it may be more appropriate to evaluate the VO2max rather than the VT, because the former variable can be reliably determined in these individuals whereas the latter lacks consistency.

Adolescent↗
PubMed1992

The case of a newspaper phobia in a 9-year-old child.

The case of E, a 9-year-old, male, with a newspaper phobia, is presented. The phobia developed over a 4-year period and gradually spread until it included many significant areas of E's life. Treatment took place over a 4-month period. It involved use of a token economy administered by E's parents. Cognitively, the treatment involved the concepts of the acquisition of perceived self-control as a consequence of the token economy agreement. This included volition, attention, and self-control by E as well as parental reinforcement.

Behavior Therapy↗
PubMed1995

Beyond determinism and materialism, or isn't it time we took consciousness seriously?

This essay argues: (1) that the fundamental conflict between the behaviorist and cognitive approaches to psychology are philosophical, not scientific; (2) that the philosophical premises underlying behaviorism (materialism, epiphenomenalism, functional model of causality, and the rejection of concepts referring to conscious states and processes) are false; and (3) that an objective, scientific approach to psychology must take consciousness and volition as axiomatic starting points.

Cognition↗
PubMed1989

Increased saccadic distractibility in tardive dyskinesia: functional evidence for subcortical GABA dysfunction.

In mammals, GABAergic projections from the substantia nigra reticulata to the superior colliculus provide tonic inhibition to tectal neurons involved in the generation of saccades. Dysfunction of this pathway has been shown to produce saccadic "distractibility" in the experimental monkey. In two oculomotor paradigms, control of saccadic eye movements was tested in chronic schizophrenic patients with (n = 18) and without (n = 16) tardive dyskinesia (TD) and normal controls (n = 8). The three groups were matched by mean age; the TD and non-TD patient groups had similar duration of illness, benztropine and chlorpromazine equivalent doses and educational levels. A twofold increase in saccadic distractibility was observed in TD compared to non-TD schizophrenic patients, and both patient groups demonstrated a greater saccadic distractibility than normals. Furthermore, schizophrenic patients (both with and without TD) showed significantly increased latency for "volitional" saccades compared to the normal controls. These findings may provide further evidence for basal ganglia GABA dysfunction in tardive dyskinesia, as well as demonstrate oculomotor abnormalities in schizophrenic individuals.

Adult↗
PubMed1990

Further analysis of the control of voluntary saccadic eye movements in schizophrenic patients.

Many schizophrenic patients reveal abnormalities in the antisaccade task. To better understand the nature of these abnormalities, in the present study we have assigned to schizophrenics the no-saccade task (subjects were required to remain fixated without being disturbed by a reflexive saccade) and memory-saccade task (subjects were required to look at a remembered target) in addition to the antisaccade and saccade tasks used previously. Many schizophrenics revealed higher error rates in the no-saccade task, and latencies of saccades to a memorized target were significantly longer than controls in the memory-saccade task. Peak velocities of saccades of large amplitudes in the memory-saccade and antisaccade tasks (but not in the saccade task) were significantly slower and durations of such saccades were longer than normal controls despite the similarity between the distributions of amplitudes of such saccades between the patients and controls. These results suggest that many schizophrenics have difficulty suppressing reflexive saccades and initiating and executing appropriate volitional saccades when the goal for the movements is known but not visible.

Adolescent↗
PubMed1991

Tobacco smoking increases square-wave jerks during pursuit eye movements.

Smooth-pursuit eye-movement (SPEM) abnormalities have been consistently observed in schizophrenia. The SPEM changes in schizophrenia are not thought to be an artifact of voluntary attention or medication, although a number of nondisease factors are known to affect SPEM. However, cigarette smoking has recently been reported to deteriorate SPEM in both smokers and nonsmokers. This finding is particularly relevant to schizophrenia, because schizophrenic patients smoke cigarettes considerably more than do normals, and none of the previous studies in this patient group have controlled for smoking. The current study was initiated to examine the effects of smoking on a number of oculomotor measures, including SPEM in smoker and nonsmoker normal volunteers. The results of this study suggest that cigarette smoking induces or significantly increases square-wave jerks, especially during smooth pursuit in normals. However, the effect is small and the global qualitative SPEM score is not affected. Other eye movements such as latencies for reflex and volitional saccades and saccadic distractibility are also unaffected by smoking. No differences were apparent between chronic smokers and nonsmokers under nonsmoking conditions in any of the eye-movement measures.

Adult↗
PubMed1996

Auditory event-related potentials, auditory digit span, and clinical symptoms in chronic schizophrenic men on neuroleptic medication.

The aim of this study was to test predictions based on Grossberg's theories of overarousal in neural networks as related to schizophrenic symptomatology. We predicted that symptoms of blunted affect and volition would be associated with reduced P300 amplitude, while impaired attention and short-term memory and symptoms of disorganization would be associated with increased N200 and P300 latency. Event-related potentials, elicited by auditory stimuli, were recorded in 20 chronic schizophrenic men on neuroleptic medication and an age- and sex-matched control group of 20 normal volunteers. The amplitude and latency values of the N200 and P300 waves at the vertex (Cz) were compared with clinical ratings (the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms) and with neuropsychological test scores by means of Spearman rank correlation coefficient. The patients showed a reduced P300 amplitude and an increased N200 latency. No correlation was found between the P300 amplitude and the symptom scores. The N200 latency was negatively correlated with auditory digit span and positively correlated with high global scores for attentional impairment, alogia, and positive formal thought disorder. Our initial predictions are partly confirmed by the apparent association between increased N200 latency and symptoms of disorganization.

Affective Symptoms↗
PubMed1982

Cortical lesion effects and vocalization in the squirrel monkey.

The effects of bilateral destruction of the cortical face area, anterior and posterior supplementary motor area and anterior cingular cortex on spontaneous vocalization were studied in 16 squirrel monkeys (Saimiri sciureus). Each type of lesion was made in two groups of two animals each. Both animals of a group received the same type of lesion at the same day. Each group was recorded for 10 sessions of one hour before operation and 10 sessions after operation. Pre- and post-operative vocalizations were compared in respect to total number and acoustic structure. It was found that none of the lesions affected acoustic structure as judged by a sonagraphic analysis. However, lesions in the anterior supplementary motor area (at the level of the callosal genu) reduced the total vocalization number significantly. This decrease was essentially due to a drastic reduction of the so-called isolation peep, a long-distance contact call. The results suggest: (i) that the cortical face area is only involved in the control of learnt vocal utterances (such as human speech and song) but not in the production of genetically preprogrammed utterances (such as monkey calls and human pain groans); (ii) that the anterior cingulate cortex is necessary for the volitional initiation of vocalization but not for the initiation of calls in an emotional situation; (iii) that the posterior supplementary motor area does not play any role in vocal behaviour of monkeys; and (iv) that the anterior supplementary motor area is involved in the production of vocalization which are not triggered directly by external events.

Animals↗
PubMed1987

Response synergies over a single leg when it is perturbed during the complex rhythmic movement of pedalling.

Previous studies report that perturbing the posture of humans evokes specific patterns of muscular synergies in the legs. This study investigated the pattern of muscular responses of a whole limb when it was rapidly perturbed in the phase of extending during stationary pedalling. Subjects were instructed to resist. Accordingly, we anticipated increased extensor activity at knee and ankle to overcome the perturbation. This did not occur in the initial responses, appearing at latencies of 85-132 ms (mean = 104 ms). In contrast, there was facilitation in tibialis anterior, and the knee extensors vastus medialis and rectus femoris, together with profound inhibition of the ankle extensors soleus and lateral gastrocnemius. The anticipated extensor response across the limb appeared in the subsequent pattern of electromyogram (EMG) activity, with latencies ranging from 121 to 195 ms (mean = 168 ms), together with a large increase in propulsive force on the pedal. The difference in EMG patterns and latencies between initial and subsequent synergies was used to separate the responses into an earlier 'prevolitional' and a later 'volitional' component.

Adult↗
PubMed1992

Modification of medullary respiratory-related discharge patterns by behaviors and states of arousal.

The modulatory influences of behaviors and states of arousal on bulbar respiratory-related unit (RRU) discharge patterns were studied in an unanesthetized, freely behaving guinea pig respiratory model system. When fully instrumented, this model system permits concurrent monitoring and recording of (i) single units from either Bötzinger complex or nucleus para-ambiguus; (ii) electrocorticogram; and, (iii) diaphragmatic EMG. In addition to being used in surveys of RRU discharge patterns in freely behaving states, the model system also offered a unique opportunity in investigating the effects of pentobarbital on RRU discharge patterns before, throughout the course of, and during recovery from anesthesia. In anesthetized preparations, a particular RRU discharge pattern (such as tonic, incrementing or decrementing) typically displayed little, if any notable variation. The most striking development following pentobarbital was a state of progressive bradypnea attributable to a significantly augmented RRU cycle duration, burst duration and an increase in the RRU spike frequencies during anesthesia. In freely behaving states, medullary RRU activities rarely adhered to a fixed, immutable discharge pattern. More specifically, the temporal organization (such as burst duration, cycle duration, and the extent of modulation of within-burst spike frequencies) of RRU discharge patterns regularly showed complex and striking variations, not only with states of arousal (sleep/wakefulness, anesthesia) but also with discrete alterations in electrocorticogram (ECoG) activities and a multitude of on-going behavioral repertoires such as volitional movement, postural modification, phonation, mastication, deglutition, sniffing/exploratory behavior, alerting/startle reflexes. Only during sleep, and on occasions when the animal assumed a motionless, resting posture, could burst patterns of relatively invariable periodicity and uniform temporal attributes be observed. RRU activities during sniffing reflex is worthy of further note in that, based on power spectrum analyses of concurrently recorded ECoG activities, this particular discharge pattern was clearly associated with the activation of a 6-10 Hz theta rhythm. These findings indicated that bulbar RRU activity patterns are subject to change by not only behaviors and sleep/wakefulness cycles, but also a variety of modulatory influences and feedback/feedforward biases from other central and peripheral physiological control mechanisms.

Animals↗
PubMedDate not supplied

Obsessive-compulsive disorder: its conceptual history in France during the 19th century.

Until the 1850s, obsessive-compulsive phenomena were considered to be a variant of the old notion of insanity. Around this time they became a separate disease: first, as a member of the old class of the neuroses; then, briefly, as a variant of the newly formed notion of psychosis; and finally, as a neurosis proper (in the post-1880s sense). These changes reflected theoretical shifts in the definition of the grand psychiatric categories. After 1860, organic causal hypotheses for OCD included dysfunctions of the autonomic nervous system and cortical blood supply. Psychological hypotheses suggested the OCD might result from volitional, intellectual, or emotional impairment, the last of which predominated after 1890. Issues relating OCD to personality types and hereditability were dealt with in terms of the degeneration theory. By the late 1880s, OCD achieved full clinical and nosological definition.

France↗
PubMedDate not supplied

European views on personality disorders: a conceptual history.

A historical account is offered of the European origins of the DSM-III-R category, personality disorder, and a differentiation is made between the history of terms, patterns of behaviors, and concepts. The concept of "disorder of character (personality)" developed in the nineteenth century, and was possible after notions such as character, constitution, temperament, and self received a psychological definition, and after the insanities became transformed into "psychoses." Terms such as "type" and "trait" were in turn ushered into the nineteenth century by faculty psychology and the phrenological tradition. Until the end of that century, "personality" referred to the subjective aspects of the self, and "personality disorder" meant alteration of consciousness (e.g., hysterical dissociation); the behavioral patterns dealt with by DSM-III-R as personality disorders were then called disorders of character and explained as states of volitional failure, or loss of coherence between cognitive, emotional, and conative functions, or of "automatism," i.e., the manifestation of lower (more primitive or animal) forms of behavior escaping the control of higher (human) ones. Character types and disorders were first considered as forms of attenuated insanity, and later on were made into a separate group whose membership could be attained via the visitation of a degeneration taint, neurological disease (e.g., encephalitis), or plain ill-breeding. The relevance of the intellectual background of the nineteenth century to these diagnostic changes is also discussed.

Europe↗
PubMed1977

Effects of voluntary isometric and isotonic activity on late transcortical reflex components in normal subjects and hemiparetic patients.

When the median nerve is stimulated at the wrist during voluntary contraction of m. abductor pollicis brevis (APB) EMG activity of this muscle contains different distinct responses: a direct muscular response (M response), a spinal reflex response (S response) and a third late reflex response, first described by Upton et al. (1971) as a second volitional reflex response (V2). Comparison of this very likely long-loop reflex involving pathways to and from the cortical level (therefore labelled C response) under isometric (hold) and isotonic (move) contraction revealed a strong facilitation of the response under the latter condition. Repetitive trains of stimuli had stronger facilitatory effect on the occurrence of this late reflex response than single stimuli. Cutaneous stimuli of the median nerve afferents did not exhibit M and S responses but definite late excitatory responses with similar latencies to the C responses. In cases of hemiparesis (mild to severe loss of sensorimotor control of finger movements) the C response was diminished, delayed or absent. These findings together with recent primate and human experimental work support the hypothesis of a transcortical stretch reflex. On the premise that muscular as well as cutaneous afferents contribute to the afferent cortical input the late C response can be interpreted as the efferent component. The C response may be a valuable aid in the diagnosis of small lesions of the sensorimotor cortex and internal capsule.

Adult↗