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PubMed2006

Effect of intravenous infusion of glyceryl trinitrate on gastric and small intestinal motor function in healthy humans.

BACKGROUND: Glyceryl trinitrate is a donor of nitric oxide that relaxes smooth muscle cells of the gastrointestinal tract. Little is known about the effect of glyceryl trinitrate on gastric emptying and no data exist on the possible effect of glyceryl trinitrate on small intestinal transit. AIM: To examine the effect of intravenous infusion of glyceryl trinitrate on gastric and small intestinal motor function after a meal in healthy humans. METHODS: Nine healthy volunteers participated in a placebo-controlled, double-blind, crossover study. Each volunteer was examined during intravenous infusion of glyceryl trinitrate 1 microg/kg x min or saline. A gamma camera technique was used to measure gastric emptying and small intestinal transit after a 1600-kJ mixed liquid and solid meal. Furthermore, duodenal motility was assessed by manometry. RESULTS: Glyceryl trinitrate did not change gastric mean emptying time, gastric half emptying time, gastric retention at 15 min or small intestinal mean transit time. Glyceryl trinitrate did not influence the frequency of duodenal contractions, the amplitude of duodenal contractions or the duodenal motility index. CONCLUSIONS: Intravenous infusion of glyceryl trinitrate 1 microg/kg x min does not induce major changes in gastric or small intestinal motor function after a 1600-kJ meal in healthy volunteers.

Cross-Over Studies↗

PubMed1989

Drinking behavior and motor function in rat pups depleted of brain dopamine during development.

The ability of rat pups depleted of brain dopamine (DA) at either 3 or 15 days of age to increase fluid intake in response to intracellular dehydration was studied. Despite near-total depletions of striatal DA, animals depleted at either age ingested normal amounts of fluid even as soon as 3-7 days after incurring the brain damage. The effects of DA receptor blockade on ingestion and motor function were also studied. Haloperidol had markedly different effects as a function of the age at which the depletions were sustained. Weanlings that were depleted of DA at 3 days of age failed to exhibit the drug-induced adipsia, akinesia, and catalepsy seen in controls and animals that were depleted at 15 days of age. These findings suggest that the DA depletions were performed at different periods of brain organization. The resultant neural controls of ingestion and motor function are qualitatively different in the two groups of depleted animals. Rats depleted at 3 days of age utilize nondopaminergic mechanisms, whereas animals lesioned at 15 days of age continue to rely upon residual DA neurons for both behaviors.

Animals↗

PubMed2004

Abnormal motor function persists following recovery from perinatal copper deficiency in rats.

What are the biochemical and behavioral consequences of perinatal copper deficiency? Pregnant Holtzman rats were fed a modified AIN-76A diet low in copper (0.34 mg Cu/kg and 42 mg Fe/kg) starting on gestation d 7. Seven rats received copper in their drinking water (20 mg Cu/L) (+Cu) and 7 drank deionized water (-Cu). Treatments did not affect litter size or pregnancy outcome. Compared with +Cu dams and a sample of +Cu male weanling [postnatal day (P)21] offspring, -Cu rats exhibited signs consistent with copper deficiency. P21 males were switched to a nonpurified copper-adequate diet and sampled biochemically after 3 mo and behaviorally after 3 and 6 mo of repletion (CuR). Compared with controls, CuR rats had lower brain copper and iron levels 3 and 6 mo after repletion; other biochemical differences were not detected. Behavioral assessments after 5 mo of repletion indicated a persistent impairment in motor function of CuR compared with control rats as evaluated by the accelerating rotorod procedure. These results suggest that permanent impairment to motor function can persist after long-term recovery from perinatal copper deficiency.

Animals↗

PubMed1991

Cholecystokinin cholescintigraphy: detection of abnormal gallbladder motor function in patients with chronic acalculous gallbladder disease.

CCK cholescintigrams were performed in 374 patients with recurrent postprandial right upper quadrant pain, biliary colic, and a normal gallbladder sonogram and/or cholecystogram. The results of these examinations were correlated with the patients' final medical/surgical diagnoses. Twenty-seven patients recruited as control volunteers without objective clinical evidence of biliary disease also underwent CCK cholescintigraphy to determine if the degree of gallbladder contraction post-CCK differs in symptomatic versus asymptomatic subjects. Decreased gallbladder motor function was identified (maximal gallbladder ejection fraction response to CCK less than 35%) in 94% of patients with histopathologically confirmed chronic acalculous cholecystitis or the cystic duct syndrome and in 88% of patients clinically believed to have chronic acalculous biliary disease. Decreased gallbladder motor function does not distinguish symptomatic from asymptomatic gallbladder disease.

Cholecystokinin↗

PubMed2000

Colonic motor function in humans is not affected by gender.

Functional abdominal pain, including the irritable bowel syndrome, is more common in females. Our aim was to determine if differences in motility or biomechanical properties of the colon could account for this gender difference. In 18 healthy subjects (nine males), a catheter assembly incorporating a balloon and perfused side holes, connected to a barostat, was positioned in the left colon. The system was used to determine compliance, sensation in response to phasic balloon distension, and changes in motor activity and tone in response to a meal. There was no significant difference in any of these variables between males and females. We conclude that there is no gender difference in colonic motor function or sensation to balloon distension. The increased prevalence of irritable bowel syndrome in females may be related to psychosocial factors rather than differences in colonic motor function.

Catheterization↗

PubMed2003

A four-year longitudinal study of palatal plate therapy in children with Down syndrome: effects on oral motor function, articulation and communication preferences.

The orofacial function in 20 children with Down syndrome was evaluated after 4 years of palatal plate therapy in 9 of the children (PPG); the remaining 11 were untreated age-matched controls (CG). All 20 children had received continuous orofacial physical therapy from their speech therapist during the treatment period. A clinical extra- and intraoral examination was performed, including oral motor function, facial expression, the occurrence of malocclusions, and hypertrophic tonsils. A questionnaire requesting data on breathing patterns, drooling, eating problems, and communicative preferences was answered by the parents. An articulation assessment was performed by two speech and language pathologists blinded to the treatment status of the children in order to find out whether the palatal plate had stimulated to improved oral speech behavior. The results for oral motor function showed significant differences between the groups in favor of the PPG for the summary variables for: visible tongue (P < 0.01), visible tongue during non-speech periods (P < 0.05), and lip-rounding during spontaneous speech (P < 0.01). During non-speech time, the PPG had their mouths open significantly less than the CG (P < 0.05). Expressivity of facial expression on a visual analog scale in the PPG scored 75.6 +/- 13.3 compared to 51.8 +/- 25.7 in the CG (P < 0.05). The intraoral examination showed that 6/9 children in the PPG and 7/11 in the CG had enlarged tonsils, resulting in more than 50% inter-tonsillary space reduction. Despite these findings, and no significant differences between the groups with respect to mouth/ nose breathing, nocturnal snoring was significantly less in the PPG than in the CG (P < 0.05), according to the parental questionnaire. After 4 years of palatal plate therapy, orofacial function had improved significantly in the 9 PPG children and specifically in terms of tongue position and lip activity.

Articulation Disorders↗

PubMed2005

Transplantation of neural cells derived from retinoic acid-treated cynomolgus monkey embryonic stem cells successfully improved motor function of hemiplegic mice with experimental brain injury.

We induced neural cells by treating cynomolgus monkey embryonic stem (ES) cells with retinoic acid. The treated cells mainly expressed betaIIItubulin. They further differentiated into neurons expressing neurofilament middle chain (NFM) in elongated axons. Half of the cells differentiated into Islet1+ motoneurons in vitro. The monkey ES-derived neural cells were transplanted to hemiplegic mice with experimental brain injury mimicking stroke. The neural cells that had grafted into periventricular area of the mice distributed extensively over the injured cortex. Some of the transplanted cells expressed the neural stem/progenitor marker nestin 2 days after transplantation. The cells expressed markers characteristic of mature motoneurons 28 days after transplantation. Mice with the neural cell graft gradually recovered motor function, whereas control animals remained hemiplegic. This is the first demonstration that neural cells derived from nonhuman primate ES cells have the ability to restore motor function in an animal model of brain injury.

Animals↗

PubMed1994

Sex hormones affect muscle contractility and motor functional recovery following peroneal nerve crush.

This study was performed to investigate possible sex differences in the contractile responses of the reinnervated extensor digitorum longus (EDL) muscle. Electromechanical studies on muscle stimulated indirectly through its nerve provided information on muscle contractility during early reinnervation. Locomotor functional recovery was followed by analyzing changes in footprint parameters over time. At 9 days postsurgery, nerve crush affected negatively many isometric contractile parameters, including twitch peak rate and contraction amplitude, as well as tetanic peak rate, contraction amplitude, and half relaxation time (HRT), regardless of sex. Female EDLs had a greater tetanic peak contraction amplitude and fully recovered twitch HRT levels. While this sex difference is clearly apparent in muscle contractility, it was abolished when considering motor functional recovery. Locomotor tests were less sensitive in demonstrating sex differences during recovery from nerve crush. Peroneal functional index (PFI), a parameter well-described by Bain in 1989, is a paradigm which compares all footprint changes incurred in a rat after peroneal nerve crush, using data obtained from uncrushed side to normalize values. PFI indicated that removal of the sex steroids seriously hindered recovery of motor function regardless of gender.

Adrenocorticotropic Hormone↗

PubMed1999

Motor function in diabetic neuropathy.

In contrast to sensory and autonomic disturbances motor function has seldomly been studied in diabetic neuropathy. Recently quantitative studies of long-term type 1 diabetic patients have shown that the strength of the ankle and knee extensors and flexors are moderately impaired. The weakness is closely related to the severity of neuropathy. Applying quantitative electromyography the degree of reinnervation is related to the muscle strength in diabetic patients suggesting the reinnervation to be insufficient. Magnetic resonance imaging of the distal part of the leg has revealed substantial muscular atrophy closely related to the degree of muscle weakness. The present findings indicate that diabetic neuropathy often is a mixed sensory-motor neuropathy.

Diabetic Neuropathies↗

PubMed2004

Transplantation of motoneurons derived from MASH1-transfected mouse ES cells reconstitutes neural networks and improves motor function in hemiplegic mice.

Mouse embryonic stem (ES) cells were transfected with a MASH1 expression vector and G418-resistant cells were selected. The MASH1-transfected cells became neuron-like appearance and expressed betaIIItubulin and panNCAM. Glial fibrillary acidic protein (GFAP) and galactocerebroside (GalC)-expressing cells were rarely detected. Half of the neural cells differentiated into the Islet1+ motoneuron lineage. Thus, we obtained motoneuron lineage-enriched neuronal cells by transfection of ES cells with MASH1. A hemiplegic model of mice was developed by cryogenic injury of the motor cortex, and motoneuron lineage-enriched neuronal cells were transplanted underneath the injured motor cortex neighboring the periventricular region. The motor function of the recipients was assessed by a beam walking and rotarod tests, whereby the results gradually improved, but little improvement was observed in vehicle injected control mice. We found that the grafted cells not only remained close to the implantation site, but also exhibited substantial migration, penetrating into the damaged lesion in a directed manner up to the cortical region. Grafted neuronal cells that had migrated into the cortex were elongated axon-positive for neurofilament middle chain (NFM). Synaptophysin immunostaining showed a positive staining pattern around the graft, suggesting that the transplanted neurons interacted with the recipient neurons to form a neural network. Our study suggests that the motoneuron lineage can be induced from ES cells, and grafted cells adapt to the host environment and can reconstitute a neural network to improve motor function of a paralyzed limb.

Animals↗

PubMed1975

Effect of glucagon on esophageal motor function.

This study evaluates the effect of exogenous glucagon on esophageal motor function in man. Manometric studies were performed using an infused catheter system. Resting lower esophageal sphincter (LES) pressure was monitored before and after intravenous pulse doses of glucagon (1 to 100 mug). The effect of glucagon (0 mug ) on esophageal peristalsis was also studied. Multiple blood samples were taken for determination of glucagon, insulin, and glucose concentration. Glucagon effect on LES pressure was also evaluated after LES stimulation by continuous intravenous infusion and pentagastrin (0.04 mug per kg per min). Glucagon caused a transient significant decrease of LES pressure only at pulse doses (20 and 100 mug) which caused nonphysiological elevation of plasma glucagon levels. The temporal profile of decreased LES pressure correlated closely with maximal blood glucagon levels. Glucagon caused no demonstrable change in esophageal peristalsis. During LES stimulation by pentagastrin, glucagon caused significant transient decreases of LES pressure at doses as low as 1 mug per kg. We conclude that glucagon at sufficient dosage has an inhibitory effect on LES pressure. This inhibitory effect is not mediated through changes in serum insulin or glucose and appears to be pharmacological.

Adolescent↗

PubMed2026

[Effect of electroacupuncture combined with suspension exercise therapy on lower limb motor function in elderly patients with post-stroke spastic hemiplegia].

OBJECTIVE: To observe the efficacy of electroacupuncture (EA) combined with suspension exercise therapy in elderly patients with post-stroke spastic hemiplegia and its effect on lower limb motor function. METHODS: A total of 120 elderly patients with post-stroke spastic hemiplegia were enrolled. Using a 2×2 factorial design, all the patients were assigned to a group A (conventional treatment), a group B (conventional treatment combined with suspension exercise therapy), a group C (conventional treatment combined with EA at Jiaji [EX-B2] and limb acupoints), and a group D(conventional treatment combined with suspension exercise therapy and EA at Jiaji [EX-B2] and limb acupoints), with 30 patients in each group. The main acupoints were bilateral Jiaji (EX-B2) points at the C2-C7, T2-T12, L1-L5, and S1 segments. The adjunct acupoints included Jianyu (LI15), Binao (LI14), Huantiao (GB30), Chengfu (BL36), etc. on the affected side.Continuous wave was applied at a frequency of 100 Hz with a current intensity of 1.5-3.0 mA, and needles were retained for 30 min, once daily for 4 weeks. Before treatment and after 2 and 4 weeks of treatment, the modified Ashworth scale (MAS),Fugl-Meyer assessment (FMA), Berg balance scale (BBS), and Barthel index scores were evaluated in the four groups. Root mean square (RMS) values of surface electromyography (sEMG) of the erector spinae and rectus abdominis muscles on the affected side, as well as balance function indexes, including the mean pressure symmetry index (SI), contact area SI, ellipse area, and displacement distances of the center of pressure in the anteroposterior (AP) and mediolateral (ML) directions, were measured. Clinical efficacy was also compared among the four groups. RESULTS: After 2 and 4 weeks of treatment, MAS scores in all groups were lower than those before treatment (P<0.05), whereas FMA, BBS, and Barthel index scores were higher than those before treatment (P<0.05). After 4 weeks of treatment, MAS scores were lower than those after 2 weeks of treatment (P<0.05), whereas FMA, BBS, and Barthel index scores were higher than those after 2 weeks of treatment (P<0.05) in the four groups. At both 2 and 4 weeks after treatment, group D had lower MAS scores (P<0.05) and higher FMA,BBS, and Barthel index scores (P<0.05) than the other three groups. After 2 and 4 weeks of treatment, RMS values of sEMG of the erector spinae and rectus abdominis muscles on the affected side at all tested angles were higher than those before treatment in all groups (P<0.05), and the values after 4 weeks of treatment were higher than those after 2 weeks of treatment(P<0.05). At both 2 and 4 weeks after treatment, all these indexes in the group D were higher than those in the other three groups (P<0.05). After 2 and 4 weeks of treatment, the mean pressure SI, contact area SI and ellipse area of each group were lower than those before treatment (P<0.05). After 4 weeks of treatment, the mean pressure SI, contact area SI and ellipse area of each group were lower than those after 2 weeks of treatment (P<0.05). After 2 and 4 weeks of treatment, the AP displacement distances of groups A, C and D were lower than those before treatment (P<0.05), and after 4 weeks of treatment, the AP displacement distances of groups A, C and D were lower than those after 2 weeks of treatment (P<0.05);after 2 weeks of treatment, there was no statistically significant difference in AP displacement distance in the group B compared with before treatment (P>0.05), and after 4 weeks of treatment, the AP displacement distance of group B was lower than that before treatment (P<0.05). After 2 weeks of treatment, there was no statistically significant difference in ML displacement distance in group A compared with before treatment (P>0.05); after 4 weeks of treatment, the ML displacement distance of group A was lower than that before treatment (P<0.05). After 2 and 4 weeks of treatment, there was no statistically significant difference in ML displacement distance in the group B compared with that before treatment (P>0.05).After 2 and 4 weeks of treatment, the ML displacement distances of groups C and D were lower than those before treatment(P<0.05), and after 4 weeks of treatment, the ML displacement distances of groups C and D were lower than those after 2 weeks of treatment (P<0.05). At both 2 and 4 weeks after treatment, mean pressure SI, contact area SI, ellipse area, and AP and ML displacement distances in the group D were lower than those in the other three groups (P<0.05). Factorial analysis of variance showed that EA had the strongest main effect on FMA score (F=6.243, P<0.05), suspension exercise therapy had the strongest main effect on BBS score (F=6.292, P<0.05), and the interaction effect was most significant for MAS score (F=5.941, P<0.05), indicating that the combined therapy produced a greater synergistic effect on reducing muscle tone than on the other outcome measures. The total effective rate in the group D was 93.3% (28/30), which was higher than those in the group A (53.3% [16/30]), group B (56.7% [17/30]), and group C (66.7% [20/30], P<0.05). CONCLUSION: EA combined with suspension exercise therapy could effectively promote the recovery of lower limb function in elderly patients with post-stroke spastic hemiplegia, improve motor and balance functions, and enhance activities of daily living.

Humans↗

PubMed1982

Effects of bile acids on human colonic motor function in vitro.

The effect of bile acid perfusion on colonic motor function in vitro has been studied. It was found that bile acid perfusion and carbachol perfusion had no effect on the frequency or incidence of slow wave activity. However, the secondary bile acid deoxycholic acid (15 mmol/l) was shown to cause a statistically significant increase in percentage motility of the isolated colon (control 24.2 + 5.5%, deoxycholic acid 64.9 + 7.3%, p less than 0.01). The magnitude of this increase was similar to the increased colonic motility recorded during carbachol (2.5 micrograms/cm3) infusion. Chenodeoxycholic and cholic acids did not increase colonic motility in vitro.

Bile Acids and Salts↗

PubMed2000

Altered regulation of dopaminergic activity and impairment in motor function in rats after subchronic exposure to styrene.

Animal and human studies suggest a dopamine-mediated effect of styrene neurotoxicity. However, the results reported to date are incomplete and not consistent. As such, the mechanism of its neurotoxicity is still unclear. The present study has, therefore, reexamined the central dopaminergic system in relation to some neurobehavioral effects in rats following subchronic exposure to styrene. Groups of adult male Sprague-Dawley rats received 0, 0.25, or 0.5 g styrene per kg b.wt. by gavage for 13 consecutive weeks. Twenty-four hours after cessation of such treatment with the higher dose (0.5 g/kg), the contents of dopamine (DA) and its metabolites were significantly reduced in the corpus striatum, hypothalamus, and lateral olfactory tract regions. In vitro styrene showed a significant increase in DA release from rat striatal synaptosomes similar to that of tyramine. Significant loss of motor function was observed on days 56, 70, and 84 during the styrene treatment with the higher dose, and lasted over a month after such treatment. However, the treated animals recovered their motor function within 45-60 days after cessation of such treatment, along with the recovery of normal levels of dopamine and its metabolites. Furthermore, styrene-induced initial impairments in measures of dopaminergic activity cannot be attributed to altered regulation of tyrosine hydroxylase activity. Specific [3H]-spiroperidol binding was also unaltered 7 or 15 days after subchronic treatment with styrene. These data imply that despite the dopaminergic neuronal loss due to styrene, dopaminergic transmission was not reduced to a level that would result in an overall development of dopamine receptor supersensitivity in the striatum. Collectively, these studies indicate that the subchronic neurotoxic action of styrene may be primarily presynaptic in nature and may involve impaired regulation of DA content and stimulation of DA release.

Animals↗

PubMed2004

Searching for motor functions in dysgenic cortex: a clinical transcranial magnetic stimulation and functional magnetic resonance imaging study.

OBJECT: Cortical motor organization/reorganization was studied in patients with malformation of cortical development (MCD) by applying two noninvasive motor mapping techniques: transcranial magnetic stimulation (TMS) and functional magnetic resonance (fMR) imaging. METHODS: Eight patients (age range 6-22 years), all suffering from congenital hemiparesis of similar severity, were included. Underlying lesions were schizencephalies in four cases, nonschizencephalic polymicrogyria in one, and complex hemispheric malformations in three. All MCDs involved rolandic cortex of the hemisphere contralateral to the hemiparesis. Transcranial magnetic stimulation was used to search, in both hemispheres, for brain regions with corticospinal projections to the paretic hand, and cortical activation during simple repetitive movements of the paretic hand was monitored using fMR imaging. Transcranial magnetic stimulation identified abnormal ipsilateral corticospinal projections from the contralesional hemisphere to the paretic hand in six of eight patients, in all of whom fMR imaging activation of the contralesional hand area was demonstrated during paretic hand movement. In two patients with schizencephaly in this subgroup, additional activation was shown in the affected hemisphere, located in dysgenic cortex lining the schizencephalic clefts but without TMS evidence for corticospinal projections originating from these sites. Corticospinal projections to the paretic hand originating in the MCD were identified in the remaining two patients, one with (nonschizencephalic) polymicrogyria and one with a complex hemispheric malformation. CONCLUSIONS: Malformations of cortical development can show various degrees of participation in motor functions, ranging from corticospinal ("primary") motor control, to putative participation as "nonprimary" motor areas, to absence of evidence for any functional participation. This information can be obtained, noninvasively, using a combination of TMS and fMR imaging.

Adolescent↗

PubMed2003

Biomechanical evaluation of the motor function of the thumb.

An experimental apparatus was developed to measure force production of a digit at various points of force application along the digit and in any direction within the transverse plane of the longitudinal axis of the digit. Eight normal subjects with asymptomatic hands were tested. Maximum voluntary isometric contraction forces were measured at the interphalangeal joint of the thumb in 16 directions that were evenly distributed within 360 degrees. Peak forces measured in all directions were used to create polar plots and to construct force envelopes using cubic spline interpolation. The areas of the force envelope and force quadrants were then calculated. The force produced by the thumb was dependent on the direction of force application. The highest force, 104.8 +/- 14.2 N, was generated in flexion, while the lowest force was generated in extension. The forces in extension, abduction and adduction were 24.8%, 57.2%, and 46.2% of the flexion force, respectively. Relatively high forces were generated in the directions of flexion combined with abduction, and flexion combined with adduction. The area of the entire force envelope was found to be 12,142 +/- 3,149 N-N. The percentage quadrant areas, relative to the total force envelope area, for extension-adduction, extension-abduction, flexion-abduction, and flexion-adduction were 7.8%, 11.4%, 39.3%, and 41.4%, respectively. The percentage quadrant areas for extension, abduction, flexion, and adduction were 4.9%, 23.6%, 52.7%, and 18.8%, respectively. The current study provides a more advanced and comprehensive method for quantification and investigation of the motor function of the thumb, which has potential in clinical applications for diagnosis of hand disorders, evaluation of deterioration or improvement of hand motor function, and guidance of therapeutic and surgical intervention.

Adult↗

PubMed1991

Patients with duodenitis have gastric secretory and motor functions like those of duodenal ulcer patients: results of a short-term treatment with ranitidine.

Gastric acid secretion, gastric emptying of solids, and the effects of short-term treatment with 300 mg ranitidine at bedtime were evaluated in symptomatic patients with endoscopically and histologically proven duodenitis. The patients investigated had basal and pentagastrin-stimulated gastric acid hypersecretion, but normal gastric emptying times. Ranitidine brought about a significant improvement of endoscopic and histological features compared with the pretreatment findings. Endoscopic but not histological improvement was significantly better than with placebo. Furthermore, ranitidine brought about a significant reduction of weekly antacid consumption compared with placebo. Both ranitidine and placebo induced significant symptomatic improvement over basal conditions, but the difference between the two treatments did not reach statistical significance. Gastric secretory and motor functions, as well as the response to therapy, were similar in duodenitis patients with and without previous history of duodenal ulcer; the only exception was in antacid consumption, which was higher in the placebo group in those with past evidence of ulcer disease. Our results suggest that duodenitis patients have secretory and motor functions similar to those of duodenal ulcer patients. Therefore, further trials on large populations of duodenitis patients with antisecretory drugs are justified.

Adult↗

PubMed1983

Hemispheric asymmetries in motor function: II. Ordering does not contribute to left-hemisphere specialization.

Patients with unilateral brain lesions of vascular origin were administered tests designed to determine if the left hemisphere is specialized for the ordering of motor acts. Patients with left- and right-sided lesions responded similarly to manipulations of ordering demands in two motor tasks, one a test of manual sequence learning and the other a test of speeded performance. A detailed analysis of performance on an Ideational Apraxia task indicated that the deficit of patients with left-sided lesions was best characterized as a deficit in generating appropriate acts rather than ordering them. It was concluded that there is no evidence for left-hemisphere specialization for the ordering of motor acts. It was hypothesized that there are two broad stages of motor function: generation of motor "target" acts (which is lateralized to the left hemisphere) and the ordering and execution of these acts (which are not lateralized).

Brain↗