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PubMed2003

The CRF1 receptor antagonist antalarmin reduces volitional ethanol consumption in isolation-reared fawn-hooded rats.

Corticotropin releasing factor is a neuropeptide associated with the integration of physiological and behavioural responses to stress. More recently, corticotropin releasing factor has been implicated in the actions of abused drugs, including ethanol. Moreover, previous studies have demonstrated that the non-selective corticotropin releasing factor receptor antagonist, alpha-helical corticotropin releasing factor(9-41), can diminish some of the behavioural effects associated with ethanol withdrawal, whilst the selective corticotropin releasing factor(1) receptor antagonist CP-154,526 has been beneficial in decreasing stress-induced relapse into alcohol-seeking behaviour. However, as yet the ability of selective corticotropin releasing factor compounds to modulate volitional ethanol consumption has not been investigated. For these reasons the present study aims to examine the effects of antalarmin, a selective, centrally acting corticotropin releasing factor(1) receptor antagonist, on both the initiation and maintenance of ethanol consumption in isolation-reared Fawn-Hooded rats. Here we demonstrate that whilst both antalarmin and diazepam can decrease the acquisition of an ethanol-preferring phenotype by Fawn-Hooded rats, only antalarmin can alter established, volitional ethanol consumption. This ability of antalarmin to reduce established ethanol consumption is apparently unrelated to changes in ingestive behaviour, or a generalised anxiolytic action. For these reasons, such drugs may provide a new therapeutic approach for the treatment of alcoholism; however, this requires further investigation.

Alcohol Drinking↗
PubMed1997

The volitional unit: a functional concept in cortico-motoneuronal connections in humans.

We used the EMG precision decomposition technique to resolve complex EMG signals and derive information about the firing times of a family of motor units (MUs) and the force they produce. The active units shared a common behavior among their firing rates, a concept described by DeLuca et al. and termed the 'common drive'. This 'common' behavior was extracted as the average of the firing rates of MUs and found to track the subject's force trajectory. In this paper, we propose the existence of functional cortico-motoneuronal connections which provide for a large number of combinations between affector cortical motoneurons (CMNs) and effector spinal motoneurons (SMNs) for the generation of a purposeful movement. We argue that these connections provide the essential link between volition and movement and function as a 'volitional unit' which consists of the CMNs, the SMNs and the anatomical and interneuronal connections between them.

Adult↗
PubMed2002

Volitional scaling of anticipatory ocular pursuit velocity using precues.

Human subjects cannot normally perform smooth eye movements in the absence of a target. However, the repeated presentation of identical, transient target motion stimuli, preceded by warning cues, leads to the build up of anticipatory smooth pursuit (ASP) eye movements several hundred milliseconds prior to stimulus onset. The present study sought to investigate whether subjects are able to volitionally scale ASP speed, as well as select pursuit direction, in advance of target motion stimuli of random direction (left vs. right) and speed (10, 20, 30 and 40 degrees /s), given stationary precues predictive of both these target parameters. The subjects' success at this task is discussed in terms of their ability to volitionally scale the internal store of target velocity information postulated to drive ASP.

Brain↗
PubMed1984

Volitional disability and physician attitudes toward noncompliance.

We develop the concept of a volitional disability as an aid in understanding those patients who behave in ways that are harmful to themselves in spite of their desire to do otherwise. Using this concept enables us to describe their behavior as intentional but 'involuntary'. We demonstrate the clinical reality of such behavior by giving clinical examples of the behavior of those with phobic, compulsive, and addictive disorders. We then attempt to show how some kinds of self-harming behavior of noncompliant patients are similar to phobic and compulsive behavior. We propose use of the concept of volitional disability to make it easier for physicians to work with these noncompliant patients and thus to improve their ability to provide better care for them.

Adolescent↗
PubMedDate not supplied

Volitional collapse (loss of the will to live) in patients with burn injuries. Treatment strategy.

Volitional collapse, or loss of the will to live, remains one of the most vexing of the various system failures complicating serious illness or injury. It resembles, but is distinguishable from, major depression. Two features of volitional collapse may sometimes be turned to therapeutic advantage: it releases the patient from a struggle that may be dissipating already depleted energy reserves, and it transfers survival responsibility from one who has given up to others who have not. Preferred treatment involves carefully orchestrated initiatives from the patient's physician, closest friend, and spouse; their leverage derives from traditional sources, most importantly psychologic transference, bonding, and conjugal commitment. A burn unit provides an ideal environment in which to study the disorder and its response to treatment.

Adult↗
PubMed1999

Can patients perform volitional motor acts at the start of a seizure?

A seizure warning device might allow some individuals with partial seizures to protect themselves against consequences of seizures, but a prerequisite is the ability to take volitional action in response to a warning. The authors reviewed consecutive seizures in their epilepsy monitoring unit to determine whether patients could squeeze an event bulb, as instructed, at the start of their seizure. Only complex partial seizures with EEG changes and with the patient on camera were analyzed. Data were obtained from 77 patients, 42 with scalp monitoring and 35 with depth electrodes. Forty-seven percent had a left-hemisphere focus, 42% a right-hemisphere focus, and 11% multifocal seizures. The seizure focus was temporal in 68%. A magnetic resonance imaging consistent with mesial temporal sclerosis was seen in 29% of patients. Overall, 44% of the patients made at least one attempt to reach for the event bulb at the start of their seizures. Among the 72% of patients who gave a history of auras, 53% were able to press the event bulb compared to 20% with no history of auras (P = 0.016). EEG changes occurred a mean of 2.9+/-30.5 seconds after reaching for the bulb for scalp-recorded seizures (n = 20), and 16.2+/-13.7 seconds before behavior for depth-recorded seizures (n = 14, difference significant at P = 0.02). Neither seizure focus nor seizure laterality influenced the ability to press the event bulb. The authors conclude that nearly half of individuals with complex partial seizures can take volitional motor action at the start of their seizure. A method to enhance the intensity and timeliness of a seizure warning would not be wasted.

Adolescent↗
PubMed2002

Effect of volitional inhibition on cortical inhibitory mechanisms.

To investigate the effect of volitional inhibition on cortical inhibitory mechanisms, we performed transcranial magnetic stimulation (TMS) studies with a Go/NoGo reaction task in seven healthy subjects. Subjects were asked to extend their right index finger only after Go, but to remain relaxed after NoGo. Single- and paired-pulse TMS were triggered at the average reaction time for the Go response in each subject after Go or NoGo cues. Motor evoked potentials were recorded in the extensor indicis proprius (EIP) and abductor digiti minimi (ADM) muscles of right hand. Paired-pulse TMS with subthreshold conditioning stimuli at interstimulus intervals (ISIs) of 2 ms [short intracortical inhibition (SICI)] and 15 ms [intracortical facilitation (ICF)] and that with suprathreshold conditioning stimuli at ISI of 80 ms [long intracortical inhibition (LICI)] were performed in both Go/NoGo and control conditions. Inhibition of SICI was enhanced in both EIP and ADM after NoGo and was reduced only in EIP after Go. Inhibition of LICI was reduced in both muscles during both conditions, while ICF was not altered. The present results demonstrate that volitional inhibition enhances SICI but reduces LICI nonselectively. These results suggest that these two inhibitory mechanisms act differently during execution and suppression of voluntary movements.

Adult↗
PubMed1994

Volitional narratives and the meaning of therapy.

OBJECTIVES: Occupational therapy literature has long recognized meaning as central to therapy. By focusing almost exclusively on how the therapy process influences the experience of meaning, the literature has neglected to examine how the patient's experiences before therapy influence the creation of meaning in therapy. METHOD: Building on a previous study of how patients discover and recount the meaning of their own lives in volitional narratives, we investigated the effect of those narratives on the experience of therapy. RESULTS AND CONCLUSION: Our examination of the therapeutic experiences of two patients enrolled in a psychiatric day hospital program reveals how they assigned meaning to therapy as an episode within their larger volitional narrative.

Adult↗
PubMed1991

Volition, deception, and the evolution of justice.

Criminal justice is inextricably associated with the attributive concept of volition. Although the voluntary-involuntary distinction is subjectively vivid, causal research shows its poles to be inseparable, i.e., the dichotomy is deceptive. Why a bulwark of civilization should be founded on paradox, may be clarified by examining the role of self-deception in man's evolutionary heritage. Natural selection for an optimal degree of self-deception probably occurred, both to facilitate deception of others and to foster human cooperation. This contributed to the evolution of psychiatric disorders, the voluntary-involuntary continuum, and large scale social systems. Society and its members reach an equilibrium within the truth-deception continuum, manifest in individuals by conscious versus unconscious and voluntary versus involuntary, and in society by tension between what actually occurs (realism) and its organizing ideals (idealism). Three legal models of criminal justice are understood in this context: The (1) utilitarian, most realistic, is essential to social survival but vulnerable to abuse; (2) rehabilitative, at an opposite idealistic pole, better supports the image of social beneficence that helps to bind society's members; (3) retributive, most heavily grounded in volition, puts greater emphasis on individual autonomy, and reciprocally modulates the other models. All are legitimized by evolutionary traditions that antedate homo sapiens, and none is sufficient in itself. Elements of all three models necessarily coexist within any existing society, their relative strength varying with its collective values, prosperity, and perceived safety.

Criminal Law↗
PubMed1988

Responses of myopes to volitional control training of accommodation.

Twelve young, low myopes were trained to control volitionally their accommodation responses and to achieve clear focus on visual targets moved progressively outward in optical distance. The trainees participated in from 15 to 40 daily training sessions (mean = 28 sessions). All demonstrated volitional control with varying degrees of control authority. Though three of the trainees were unsuccessful, the group achieved a statistically reliable extension of their far points. Post-training optometric examinations were reliably improved over pre-training examinations, but did not appear to be commensurate with the large gains in far-point extension. It was hypothesized that the learned skill may have been 'instrument-specific', i.e. it might not fully generalize to significantly improved post-training binocular performance unless it were accompanied by clinical assistance to transfer the training.

Accommodation, Ocular↗
PubMed2000

Volitional ethanol consumption affects overall serotonin metabolism in Syrian golden hamsters (Mesocricetus auratus).

Methods were established for the determination of serotonin (5-HT)(1) metabolites 5-hydroxyindole-3-acetic acid (5-HIAA) and 5-hydroxytryptophol (5-HTOL) in the urine of Syrian golden hamsters (Mesocricetus auratus) and used to study the effect of volitional ethanol consumption on overall 5-HT metabolism in this ethanol-preferring rodent. The basal levels of 5-HIAA and 5-HTOL in 24-h urine of ethanol-naive hamsters were 300 +/- 101 and 4.96 +/- 1. 06 nmol (n = 8), respectively. Given free choice between water and a 15% ethanol solution, these hamsters chose to consume increasing amounts of ethanol. The increase was accompanied by a concomitant decrease in urine 5-HIAA and increase in urine 5-HTOL, indicating that volitional ethanol intake diverted part of the 5-HT metabolic flux from an oxidative into a reductive pathway. In a separate experiment, the amounts of ethanol consumed by and blood ethanol concentrations attained in ethanol-drinking golden hamsters were determined at 5 different time intervals between 6 PM and 7 AM when most feeding activities occurred. Except in the first hour after lights were turned off, ethanol was consumed at a relatively even pace throughout the night (2-3 g/kg/3 h) and blood ethanol levels were maintained at the low mM range which rarely exceeded 2 mM. These results suggest that the biochemical pathway that catalyzes 5-HT metabolism is extremely sensitive to ethanol and can play an important role in mediating the reported clinically beneficial action of a low concentration of ethanol during alcohol detoxification.

Animals↗
PubMed1994

Volitional vasomotor lability and vasomotor control.

This experiment tested the hypothesis that skin temperature variability during instructions to attempt skin temperature self-control without feedback (volitional vasomotor lability) predicts the acquisition of vasomotor control through biofeedback training. Skin temperature was recorded from the hands of 232 volunteers during a screening session. Twenty-three labile and 17 stabile subjects were chosen to participate in a 16-session training program under double blind conditions. Visual and auditory feedback were used to train subjects to produce temperature differences between the two hands in a specified direction. Comparisons between the labile and stabile groups revealed statistically significant differences in the predicted direction on measures of performance and learning. These findings provide preliminary support for the hypothesized positive relationship between volitional temperature variability and voluntary vasomotor control. Fruitful directions for future research are suggested.

Adult↗
PubMed1999

Age differences in postural sway during volitional head movement.

OBJECTIVE: To examine the role of a volitional self-paced head-turn movement on the postural sway characteristics of healthy young and elderly subjects. DESIGN: Cross-sectional design. SETTING: Motor control research laboratory. SUBJECTS: Ten young adults and 10 elderly subjects. MAIN OUTCOME MEASURES: Postural sway characteristics of each subject were examined using a Kistler force platform. Each subject was tested under four experimental conditions: (1) static postural sway with vision; (2) static postural sway without vision; (3) postural sway with vision and self-paced head-turn movement; and (4) postural sway with no vision and a self-paced head-turn movement. Subjects performed six 15-second trials in each experimental condition. Dependent variables analyzed on each trial were mean sway amplitude (in millimeters), sagittal sway standard deviation, lateral sway standard deviation, and frequency of sway (in hertz). RESULTS: During the static conditions (e.g., no voluntary movement), the young subjects produced significantly less postural sway than the elderly in both the vision condition (sway amplitude in the young, 3.80 mm; in the elderly, 4.89 mm) and the no-vision condition (young, 5.44 mm; elderly, 5.95 mm). This increased sway was the result of greater lateral sway in the elderly for the vision condition (3.73 vs. 2.68 mm), and greater sagittal sway for the elderly in the no-vision condition (5.55 vs. 4.70 mm). There were no significant differences between the groups in the frequency of sway. When asked to initiate and complete the head-turn, elderly subjects significantly increased their mean sway amplitude and decreased their frequency of sway, whereas the young subjects did not significantly alter their postural sway profiles. CONCLUSIONS: These results demonstrate different postural sway control strategies for young and elderly subjects when asked to perform volitional movements.

Accidental Falls↗
PubMed2002

Motivational versus volitional mediation of passivity in institutionalized older people.

The relationship between perceived loss of control and passivity in social activities in a non-handicapped institutionalized elderly population was assessed. Perceived loss of control was assessed from three different types of expectancies: low action-outcome expectancies, high situation-outcome expectancies, and low efficacy expectancies. Passivity scores were reported by the staff. The effect of these three types of expectancies on passivity was analyzed in terms of motivation and volition, which were treated as mediating variables. Overall analysis of the structural equations, as well as partial hierarchical regression analyses, showed that efficacy expectancies were good predictors of passivity, but this was not the case for the action-outcome and situation-outcome expectancies. These results lend more support to a volitional rather than to a motivational interpretation of the effect of control on passivity. The implications of these results for intervention and for a differentiated conception of expectancies are discussed.

Aged↗
PubMed2005

Intention memory and achievement motivation: volitional facilitation and inhibition as a function of affective contents of need-related stimuli.

Replicating findings of J. Kuhl and M. Kazén (1999), reduction or removal of Stroop interference was achieved after short exposure to primes eliciting positive affect. This effect was need specific: Stroop interference removal (volitional facilitation) was found with positive primes related to achievement needs but not with positive primes related to affiliation or power needs. Five studies are reported. College students and unemployed university graduates participated in 2 studies each and branch managers of a large insurance company in 1 study. Whereas Stroop interference reduction or removal was found in all groups after positive-achievement primes, the 2 groups of unemployed persons additionally showed a significant increase of Stroop interference (volitional inhibition) after exposure to primes related to negative achievement episodes. Results are discussed in the context of Kuhl's personality systems interactions theory.

Achievement↗
PubMed2005

Mapping metabolic brain activation during human volitional swallowing: a positron emission tomography study using [18F]fluorodeoxyglucose.

We have previously shown that labelled water positron emission tomography (H2(15)O PET) can be used to identify regional cerebral blood flow (rCBF) changes in the human brain during volitional swallowing. (18F) fluorodeoxyglucose (FDG PET), by comparison, uses a glucose analogue to quantitatively measure regional cerebral glucose metabolism (rCMRglc) rather than rCBF. The main advantage of FDG PET is improved spatial resolution, and because of its pharmacodynamic properties, activation can be performed external to the scanner, allowing subjects to assume more physiologic positions. We therefore conducted a study of the brain's metabolic response while swallowing in the erect seated position, using FDG PET. Eight healthy male volunteers were studied with a randomised 2 scan paradigm of rest or water swallowing at 20-second intervals for 30 minutes. Data were analysed with SPM99 using multisubject conditions and covariates design. During swallowing, analysis identified increased rCMRglc (P<0.01) in the following areas: left sensorimotor cortex, cerebellum, thalamus, precuneus, anterior insula, left and right lateral postcentral gyrus, and left and right occipital cortex. Decreased rCMRglc were also seen in the right premotor cortex, right and left sensory and motor association cortices, left posterior insula and left cerebellum. Thus, FDG PET can be applied to measure the brain metabolic activity associated with volitional swallowing and has the advantage of normal task engagement. This has implications for future activation studies in patients, especially those suffering swallowing problems after brain injury.

Adult↗
PubMed1997

Inspiratory muscle fatigue following running to volitional fatigue: the influence of baseline strength.

Respiratory muscle fatigue has been demonstrated following short-term exercise to volitional fatigue, as well as following prolonged submaximal exercise. There is some suggestion that the respiratory muscles of 'athletic' individuals have superior strength and greater fatigue resistance but it is not known whether inspiratory muscle strength influences fatigueability of the inspiratory muscles. The present study examined this question in 24 moderately trained young men. Inspiratory muscle strength was measured at residual volume using a hand held Mouth Pressure Meter before and after an incremental, multistage shuttle run to volitional fatigue. Following the run, there was a significant fall in inspiratory mouth pressures (-10.5 +/- SD 8.2%; p < 0.001 Pre- vs Post Pipeak). The subjects with the weakest inspiratory muscles exhibited significantly greater fatigue than those with the strongest (-17.0 +/- SD 7.8% c.f. 6.8 +/- SD 4.4% for the 25th and 75th percentiles respectively p < 0.01). These data support existing evidence that the respiratory muscles fatigue following high intensity exercise. In addition, they provide new evidence that this phenomenon occurs in moderately trained young men and that the severity of the fatigue is related to the baseline strength of the inspiratory muscles.

Adult↗
PubMed1995

Work and meaning: disturbance of volition and vocational dysfunction in schizophrenia.

R. is a 40-year-old, divorced, White male with a diagnosis of schizophrenia, paranoid type, chronic. Shortly after his entrance into our work rehabilitation program, R. engaged one of the authors (P.L.) in a conversation about the nature of his illness. He reported that his most disabling and pervasive symptom was a persistent inability to pursue any goal in his life. R. recognized that he had other symptoms of psychiatric illness but stated that these did not account for his disability. He explained that the voice of God that counseled him when he felt overwhelmed and his fear that God was about to kill him as punishment for his sins put life in perspective and, consequently, were sometimes as comforting as they were distressing. R. explained that what had altered his life was a process, invisible to others, that left him unable to plan out and pursue a life course. He did not know whether it was a lack of knowledge or lack of motivation and energy that left him without the inner direction he needed. All he knew was that it was "schizophrenia," and it left him unable to work or to function like other people. What R. was describing as the foundation of his illness and his disability appears to be a disturbance of volition. Interestingly, self-understanding is more consistent with several of the early formulations of schizophrenia than it is with current formulations. To explore the merits of R.'s belief about his illness we offer a review of the role that disturbance of volition has played in historical conceptualizations of schizophrenia, the current nosology, and in theories of the negative or deficit syndrome. The history of R.'s illness is then presented. Lastly, we discuss what we learned from R.'s participation in a paid work program.

Adult↗