Dexterity Test Research Articles

Grooved Pegboard Predicates More of Cognitive Than Motor Involvement in Parkinson’s Disease

The Grooved Pegboard Test (GPT) was conceived as a test of manual dexterity, upper-limb motor speed, and hand-eye coordination. The aim of our study was to test the componential structure of the GPT on an archetypal model of motor impairment, Parkinson's disease (PD). A total of 45 PD patients (33 males, 12 females; age M = 67, range = 49-81; PD duration M = 10, range = 6-20 years; H/Y stage 2, range = 2-3) and 20 age- and education-matched controls (14 males, 6 females; age M = 66, range = 48-80) were included. All participants were investigated using the GPT, Short Falls Efficacy Scale-International, Frontal Assessment Battery (FAB), Montreal Cognitive Assessment (MoCA), and Non-Motor Symptom Scale. Patients were followed for 6 months, using fall diaries and monthly phone calls to define PD fallers (falls ≥ 1; n = 27) and PD nonfallers (falls = 0; n = 18). Using structural equation modeling, the GPT predicted performance on the MoCA (p < .001), but not on the FAB (p = .29). In conclusion, analysis of the structure of the GPT provided evidence about important cognitive features, in addition to the motor component of this test in PD.

Manual Dexterity Aptitude Testing

Currently there are few validated metrics for predicting surgical skill among otolaryngology residency applicants. To determine whether manual dexterity aptitude testing in the form of soap carving during otolaryngology residency interviews at Kaiser Permanente Medical Center Oakland predicts surgical skill at the time of graduation from otolaryngology residency programs. This study was conducted to determine how applicants with the best and worst soap carvings compared at the time of graduation with respect to various metrics including visuospatial ability and manual dexterity. Over the last 25 years, applicants to the residency program at Kaiser Permanente Oakland were required to carve soap during their residency interview. The 3 best and 3 worst soap carvings from 1990 through 2006 were determined. Of the individuals who carved those soaps, 62 qualified for the study and matriculated into otolaryngology residency programs. Surveys were sent to the 62 individuals' residency programs to evaluate those individuals on a 5-point Likert scale in various categories as well as to rank those individuals as being in the top 50% or bottom 50% of their graduating class. All else being equal, we hypothesized that applicants who had the manual dexterity and visuospatial skills to accurately carve a bar of soap would more likely possess the skills necessary to become a good surgeon. There was no difference between individuals with the best soap carvings and those with the worst soap carvings in all categories: cognitive knowledge, visuospatial ability, manual dexterity, decision making, and overall score (P > .10 for all categories). There was a 95% response rate, with 35 of 37 residency programs responding and 59 of 62 surveys returned. Manual dexterity aptitude testing in the form of soap carving does not appear to correlate with surgical skill at the time of graduation. Further studies need to be conducted to determine the role of manual dexterity and visuospatial aptitude testing in the otolaryngology application process.

Hand rehabilitation using MIDI keyboard playing in adolescents with brain damage: A preliminary study

As a sequential, programmed movement of fingers, keyboard playing is a promising technique for inducing execution and a high level of coordination during finger movements. Also, keyboard playing can be physically and emotionally rewarding for adolescents in rehabilitation settings and thereby motivate continued involvement in treatment. The purpose of this study is to evaluate the effects of keyboard playing using Musical Instrument Digital Interface (MIDI) on finger movement for adolescents with brain damage. Eight adolescents with brain damage, ages 9 to 18 years (M = 13 years, SD = 2.78), in physical rehabilitation settings participated in this study. Measurements included MIDI keyboard playing for pressing force of the fingers and hand function tests (Grip and Pinch Power Test, Box and Block Test of Manual Dexterity [BBT], and the Jebsen Taylor Hand Function Test). Results showed increased velocity of all fingers on the MIDI-based test, and statistical significance was found in the velocity of F2 (index finger), F3 (middle finger), and F5 (little finger) between pre- and post-training tests. Correlation analysis between the pressing force of the finger and hand function tests showed a strong positive correlation between the measure of grip power and the pressing force of F2 and F5 on the Grip and Pinch Strength Test. All fingers showed strong correlation between MIDI results and BBT. For the Jebsen Taylor Hand Function Test, only the moving light objects task at post-training yielded strong correlation with MIDI results of all fingers. The results support using keyboard playing for hand rehabilitation, especially in the pressing force of individual finger sequential movements. Further investigation is needed to define the feasibility of the MIDI program for valid hand rehabilitation for people with brain damage.

Determinants of variability in motor performance in middle childhood: a cross-sectional study of balance and motor co-ordination skills.

BackgroundPhysical activity is a key component of exploration and development. Poor motor proficiency, by limiting participation in physical and social activities, can therefore contribute to poor psychological and social development. The current study examined the correlates of motor performance in a setting where no locally validated measures of motor skills previously existed. The development of an appropriate assessment schedule is important to avoid the potential misclassification of children’s motor performance.MethodsA cross-sectional study was conducted among a predominantly rural population. Boys (N = 148) and girls (N = 160) aged between 8 and 11 years were randomly selected from five schools within Kilifi District in Kenya. Four tests of static and dynamic balance and four tests of motor coordination and manual dexterity were developed through a 4-step systematic adaptation procedure. Independent samples t-tests, correlational, univariate and regression analyses were applied to examine associations between background variables and motor scores.ResultsThe battery of tests demonstrated acceptable reliability and validity. Variability in motor performance was significantly associated with a number of background characteristics measured at the child, (gender, nutritional status and school exposure) household (household resources) and neighbourhood levels (area of residence). The strongest effect sizes were related to nutritional status and school exposure.ConclusionsThe current study provides preliminary evidence of motor performance from a typically developing rural population within an age range that has not been previously studied. As well as being culturally appropriate, the developed tests were reliable, valid and sensitive to biological and environmental correlates. Further, the use of composite scores seems to strengthen the magnitude of differences seen among groups.

The Effects of Short-Term and Long-Term Exposure to a High Altitude Hypoxic Environment on Neurobehavioral Function

Examined the change in neurobehavioral function of individuals acclimated to high altitudes and those native to high altitudes. A neurobehavioral core test battery approved by the WHO (WHO-NCTB) was used to evaluate the effects of high altitude hypoxia on neurobehavioral function. The WHO-NCTB is composed of seven individual tests: a mood state profile, simple reaction time test, digit span test, Santa Ana manual dexterity test, digit symbol test, Benton visual retention test, and pursuit aiming test. The values from the Santa Ana manual dexterity test, digit symbol test, and pursuit aiming test from sea-level subjects acclimated for 5 days at 3700 m were significantly decreased when compared with the same subjects at sea level. The values from the digit span, Santa Ana manual dexterity, digit symbol, Benton visual retention and pursuit aiming tests in subjects native to high altitudes of 3700, 4500, and 5100 m were significantly decreased when compared with subjects at sea level and compared with sea-level subjects acclimated for 5 days at 3700 m. These results demonstrate that high altitude hypoxia induces damage to neurobehavioral functions, and the long-term deficit in neurobehavioral function was more severe than the short-term changes.

Cannabidiol attenuates deficits of visuospatial associative memory induced by Δ9tetrahydrocannabinol

Background and PurposeRecent human studies suggest that recreational cannabis strains that are relatively high in cannabidiol (CBD) content produce less cognitive impairment than do strains with negligible CBD and similar Δ9tetrahydrocannabinol (THC) content. Self‐selection in such studies means it is impossible to rule out additional variables which may determine both cannabis strain selection and basal cognitive performance level. Controlled laboratory studies can better determine a direct relationship.Experimental ApproachIn this study, adult male rhesus monkeys were assessed on visuospatial Paired Associates Learning and Self‐Ordered Spatial Search memory tasks, as well as additional tests of motivation and manual dexterity. Subjects were challenged with THC (0.2, 0.5 mg·kg−1, i.m.) in randomized order and evaluated in the presence or absence of 0.5 mg·kg−1 CBD.Key ResultsCBD attenuated the effects of THC on paired associates learning and a bimanual motor task without affecting the detrimental effects of THC on a Self‐Ordered Spatial Search task of working memory. CBD did not significantly reverse THC‐induced impairment of a progressive ratio or a rotating turntable task.Conclusions and ImplicationsThis study provides direct evidence that CBD can oppose the cognitive‐impairing effects of THC and that it does so in a task‐selective manner when administered simultaneously in a 1:1 ratio with THC. The addition of CBD to THC‐containing therapeutic products may therefore help to ameliorate unwanted cognitive side‐effects.Linked ArticleThis article is commented on by Mechoulam and Parker, pp 1363–1364 of this issue. To view this commentary visit http://dx.doi.org/10.1111/bph.12400

Hand Dexterity in Children: Administration and Normative Values of the Functional Dexterity Test

To document normative values from the Functional Dexterity Test (FTD) for typically developing children and to optimize test administration and interpretation. A total of 175 typically developing children aged 3 to 17 years participated in the study. Children completed the 16-peg FDT with both hands, and elapsed time was recorded in seconds. Data were analyzed as 16/time, interpreted as speed (pegs per second). A linear regression analysis predicted speed from age and hand dominance. Functional Dexterity Test speed increased linearly in typically developing children by 0.04 pegs/s for each year of age. This rate of increase was the same for dominant and nondominant hands. Dominant hands were faster than nondominant hands by 0.09 pegs/s at all ages. There was no sex difference. This study provides age-specific normative values for functional dexterity in typically developing children in 2 formats: as a growth chart of FDT speed versus age and as a regression model that calculates expected speed given a child's age and tested hand dominance. Recommended pediatric modifications to the FDT are to use speed (pegs per second) instead of time (seconds) to report results, and to not assess penalties. The norms presented allow clinicians to compare both speed and rate of change over time of pediatric patients with typically developing children, which makes it possible to distinguish developmental change from intervention. Diagnostic III.

A Complex Haptic Exercise to Predict Preclinical Operative Dentistry Performance: A Retrospective Study

A reliable test of manual dexterity could potentially have utility in dental education. Recently, haptic technologies have emerged that may offer a means of testing manual dexterity in the preclinical setting. The purpose of this study was to determine whether performance on a complex haptic simulator exercise was associated with preclinical operative dentistry practical examination scores or the Perceptual Ability Test (PAT) scores of the Dental Admission Test. All thirty-nine first-year dental students enrolled in the Operative Dentistry preclinical course at the Stony Brook University School of Dental Medicine completed a haptic exercise consisting of a single manual dexterity test (D-circle), repeated eight times in succession during a single session at midterm. A score reflecting accuracy and time to completion of each trial was calculated automatically and resulted in a success or failure for each trial. Preclinical operative dentistry practical examinations consisting of plastic tooth preparations given at three time points during the course were scored by four calibrated and masked course faculty members. Examination scores were compared with students' performance on the haptic test using linear regression. Number of failures during a single session on a complex haptic exercise was found to be a significant predictor of examination performance in the preclinical setting. These results suggest a role for haptics in identifying students with potential learning challenges in the preclinical stages of dental education. Identification of students with manual dexterity problems at an early stage may allow for early intervention to prevent failure.

The effects of an exercise training program on hand and wrist strength, and function, and activities of daily living, in adults with severe Cerebral Palsy

The purpose of the current study was to establish measurement reliability in adults with Cerebral Palsy (CP), and to examine the feasibility and outcomes of an upper extremity strength training program (three times per week for 90 min each time). A control group design mixed with a prospective time series design for the intervention group was completed, including a pre-test, a post-test after a 12-week intervention period, and a follow-up in the intervention group after an additional 10-week period. Seventeen adults with CP with severe motor impairment took part in the study (10 in the intervention and seven in the control group). The test battery was comprised of wrist and hand dynamometry; dominant hand upper-extremity function measures (Jebsen Hand Function Test=JHFT, Minnesota Manual Dexterity Test=MMDT, and the Nine Hole Peg Test=NHPT); and activity of daily living with the Barthel Index. The results indicated that in both the control and the intervention groups, the strength tests exhibited good-to-excellent reliability during pre-test and post-test. The group comparison revealed that while in the pre-test no between-group differences existed, in the post-test the strength training group demonstrated significantly higher values in five out of eight strength measures, as well as in the MMDT. Discontinuing the program for eight weeks reversed the effects almost to baseline. In conclusion, the outcomes demonstrated the reliability of the assessments utilized in this study, as well as the feasibility of the strength training program, in adults with severe motor impairment due to CP.

Rating Accessibility of Packaging: A Medical Packaging Example

Few previous work has been undertaken in understanding issues surrounding dexterity and access to packaging. Researchers had access to users who had known dexterity issues and had been advised by their doctor to decant their medication into bottles rather than use unit-dose blister packaging. Hence, it was decided to use a range of techniques to understand this problem. It was further proposed to develop a methodology by which the relative performance of packaging could be assessed with respect to dexterity issues.In this study, there were three objectives to carry out: motion-capture analysis, grip analysis and dexterity analysis when opening the blister packs. Motion capture was carried out on eight people aged 55 years and older, a classification of the grips used when opening blister packs was performed on 57 people aged 18 years and older, and a Purdue Pegboard test was administered to 54 people aged 18 years and older.It was found out that there were four common types of grips used, out of which two of the grips were used by more than 88% of participants. With the motion capture, it was found that each grip and their various associated techniques were compared with each other. Grip 2 utilized the least finger movement. Using the dexterity test results, it was corroborated that dexterity decreases with age, and an accessibility score was developed that can be used by pack designers and manufacturers to assess pack performance. Future work is proposed to develop this methodology further. Copyright © 2013 John Wiley & Sons, Ltd.

Towards a comprehensive Functional Capacity Evaluation for hand function

The aim of this study was to develop a more efficient (i.e. shortened) protocol for hand function capacity evaluation and to test the agreement of the protocol compared to the original protocol. 643 Healthy subjects performed tests for hand function. Agreement between two shortened protocols was compared with an existing protocol. The original protocol was performed once and the proposed shortened protocol differed in the number of trials which were reduced by statistical elimination. Agreement was determined with Intraclass Correlation Coefficients (ICC) and Limits of Agreement (LoA). Excellent ICCs (≥0.91) were observed in all proposed protocols except for the one trial purdue pegboard test protocol. For all tests of hand function, shorter protocols are valid to determine hand function. For Tip Pinch Strength testing, Palmar Pinch Strength testing and the Purdue Pegboard test, a two-trial protocol is recommended, because the LoA were considerable, which could affect decision-making with regards to hand capacity. For the Hand Grip strength test, the Key Pinch Strength test and the Complete Minnesota Dexterity Test, a one-trial protocol is recommended, because the LoA were acceptable. It was concluded that for healthy subjects, this shorter protocol is a reliable measure. Further testing of the short form hand FCE protocols should be completed on patients with disabling conditions prior to widespread use of these protocols among clinical samples.

Preliminary Evaluation of the Ergonomic Properties of Gloves for Protection Against Mineral Oils Based on Manual Dexterity Tests

Abstract The objective of this study was to conduct a preliminary evaluation of the ergonomic properties of gloves designed for protection against mineral oils. Two standardized tests were employed for assessing comfort of use: the finger dexterity test and the grip and pull test. The study was carried out under conditions simulating the real-life usage of gloves; mineral oil was spread on the gloves’ surface, which is a novelty relative to the methodology described in the relevant standards. Four types of gloves commonly used for protection against mineral oils were studied. The first test involved 10 human subjects, and the second 4 subjects. Preliminary evaluation of the ergonomic properties of gloves was conducted by means of the finger dexterity test (evaluation of fine finger movements) and a cylinder grip and pull test (evaluation of the gross movements of the arms and hands). These tests showed that mineral oil present on the surface of the gloves (in the dexterity test and the grip and pull test) negatively affected the ergonomic properties of the gloves. It was established that the glove material influenced the subjects’ evaluation of the effort put into gripping and pulling a cylinder while wearing oiled gloves. The study also showed that the cylinder grip and pull test, used to examine the gross movements of the arms and hands, is more sensitive than the finger dexterity test and allows for more accurate verification of a glove material in the case of exposure to oils. It should be noted that gloves made entirely of chloroprene rubber exhibited the smallest decrease in ergonomic properties in the most difficult test involving oiled gloves and a cylinder. This material provides greater comfort of use than a liner coated with acrylonitrile-butadiene rubber or nitrile rubber.

Is the UNB test reliable and valid for use with adults with upper limb amputation?

Study designClinical measurement. IntroductionThe University of New Brunswick (UNB) Test of Prosthetic Function was developed for children. No studies have examined its use with adults. Purpose of the studyOur purposes were to utilize the UNB with adults to examine test–retest, inter-rater reliability and examine validity. MethodsThe UNB was administered to 51 subjects. Forty-five completed it twice within 1 week. Internal consistency was examined. Test–retest reliability and inter-rater reliability were estimated. ANOVAs compared scores by prosthetic use. Correlations between UNB scales, 2 dexterity tests (the Modified Box and Block Test, the modified Jebsen–Taylor Hand Function Test), and the self-reported Upper Extremity Functional Scale (UEFS) were examined. ResultsAlphas were 0.74–0.75 and 0.69–9.79 for spontaneity and skill respectively. ICCs for test–retest reliability and inter-rater reliability were 0.73, 0.76 for spontaneity and 0.76 and 0.79 for skill. There were no differences in scores by prosthetic experience. UNB correlations with dexterity measures were moderate, and correlations with UEFS were weak for spontaneity and non-significant for skill. ConclusionsUNB scales had acceptable reliability and preliminary evidence of validity for adults. Level of evidenceIIb.

P.7.19 Effects of upper extremity exercise training on upper extremity endurance in patients with Duchenne Muscular Dystrophy

To investigate the effects of 8 weeks upper extremity aerobic and strengthening exercises on upper extremity endurance in children with Duchenne Muscular Dystrophy (DMD). 24 children with DMD who have similar physical characteristics between 8 and 15 years of age included in the study. Children randomly divided into two groups. 12 DMD children whose functional status were between Grade 1 and 3 according to the Brooke Upper Extremity Functional Classification were included in each study and control group Minnesota Hand Dexterity Test (MHDT) was used to assess the upper extremity endurance and hand dexterity of children. Children in the study group received 45-min exercise sessions with electronic arm ergometer, 3 days a week for 8 weeks. 8-weeks home program including strengthening exercises for the upper extremity were given to the patients in control group. The number of elbow flexion–extension were recorded before and after each exercise sessions in study group. Asssessments were repeated after 8 weeks training and results were compared within and between groups. There were statistically significant decrease in unilateral placing (z = −2.354) and bilateral turning (z = −2.786) parameters of MHDT in study group (mean ages 9.5 ± 1.4) while only bilateral turning (z = −2.354) in control group (mean ages 9.3 ± 1.4) after training, compared to baseline (p

Neurocognitive disorders in sentenced male offenders: Implications for rehabilitation

Neurocognitive deficits are frequent among male offenders and tend to be associated with a more serious risk of anti-social activity, but they are not systematically allowed for in rehabilitation programmes. The aim of this study was to evaluate neurocognitive performance in a sample of sentenced Finnish male prisoners and consider the implications for prison programme entry. Seventy-five sentenced male prisoners were examined using a neurocognitive test battery. Depending on the neurocognitive domain, from 5% to 49% of the men demonstrated marked neurocognitive deficits in tests of motor dexterity, visuospatial/construction skills, verbal comprehension, verbal and visual memory and attention shift. Verbal IQ was more impaired than performance IQ. There was no association between most serious offence type and neurocognitive performance, but correlations between attention deficit indices and number of previous convictions suggested that recidivists may have an attention disorder profile. Cluster analysis identified two subgroups of offenders, separated by very poor or merely poor cognitive performance. Motor dexterity, visuo-construction and verbal memory deficits were not wholly explained by lower IQ measures. Our sample was small, but the nature and extent of the neurocognitive deficits found suggest that wider use of neurocognitive assessments, which the men generally tolerated well, could help select those most likely to need offender programmes and that the effectiveness of these may be enhanced by some specific cognitive remediation before progressing to more complex social tasks.

Distinction between hand dominance and hand preference in primates: a behavioral investigation of manual dexterity in nonhuman primates (macaques) and human subjects.

Background The present study aimed to determine and confront hand preference (hand chosen in priority to perform a manual dexterity task) and hand dominance (hand with best motor performance) in eight macaques (Macaca fascicularis) and in 20 human subjects (10 left-handers and 10 right-handers). Methods Four manual dexterity tests have been executed by the monkeys, over several weeks during learning and stable performance phases (in controlled body position): the modified Brinkman board, the reach and grasp drawer, the tube and the bimanual board tasks. Three behavioral tests, adapted versions from the monkeys tasks (modified Brinkman board, tube and bimanual board tasks), as well as a handedness questionnaire, have been conducted in human subjects. Results In monkeys, there was a large disparity across individuals and motor tasks. For hand dominance, two monkeys were rather right lateralized, three monkeys rather left lateralized, whereas in three monkeys, the different parameters measured were not consistent. For hand preference, none of the eight monkeys exhibited a homogeneous lateralization across the four motor tasks. Macaca fascicularis do not exhibit a clear hand preference. Furthermore, hand preference often changed with task repetition, both during training and plateau phases. For human subjects, the hand preference mostly followed the self-assessment of lateralization by the subjects and the questionnaire (in the latter, right-handers were more lateralized than left-handers), except a few discrepancies based on the tube task. There was no hand dominance in seven right-handers (the other three performed better with the right hand) and in four left-handers. Five left-handers showed left-hand dominance, whereas surprisingly, one left-hander performed better with the right hand. In the modified Brinkman board task, females performed better than males, right-handers better than left-handers. Conclusions The present study argues for a distinction between hand preference and hand dominance, especially in macaque monkeys.

Effects of a new sensory re-education training tool on hand sensibility and manual dexterity in people with multiple sclerosis

To describe and evaluate the effects of a new home-based sensory re-education training tool on hand sensibility and manual dexterity in people with MS experiencing upper limb sensory deficits. Twenty-five people with relapsing-remitting MS (18 women), mean age 50.6 years (SD = 11.4), volunteered to participate. Participants were initially assigned to a 7-week control phase followed by a 3-week home-based sensory re-education phase. Measurements used were the nine-hole peg test, the two point discrimination test, the monofilaments test and the functional dexterity test. Measurements were collected at baseline, following the control phase and at the end of the trial. Participants demonstrated an improvement in the nine-hole peg (26.8 (SD = 3.5) vs. 22.6 (SD = 3.2); mean difference (95% CI) 4.9 (0.9, 7.1), P = 0.03) and functional dexterity tests (38.6 (SD = 4.4) vs. 33.8 (SD = 4.9); mean difference (95% CI) 4.8 (1.8, 7.0); P = 0.02) at the end of the sensory re-education phase compared to the end of the control phase. No differences were observed as to the monofilaments and two-point discrimination tests. Sensory re-education training does not affect the level of sensory impairment in the hand but may lead to improvement in select measures of manual dexterity.

In vitro fertilization and late preterm preschoolers' neuropsychological outcomes: the PETIT study

Invitro fertilization (IVF) is considered a generally safe procedure, although associated with a higher incidence of preterm birth. The literature is inconsistent about the psychological impact of IVF, and we found no reports about outcome in late preterm (LPT) children. Our objective was to study neuropsychological and behavioral outcomes in a cohort of preschoolers born LPT between 2004 and2007. Participants were 397 LPT children (mean age, 3.8 years) conceived assisted by IVF (n= 105) or non-IVF (n= 292). Standardized performance-based tests of general conceptual ability (intelligence quotient), executive function, focused/selective attention, visual-spatial perception, visual-motor skill, manual dexterity, learning, and memory were administered. Parents completed behavioral and executive function questionnaires. IVF group characteristics included older maternal age (P < .001), lower birthweight (P < .001), and higher maternal education (P< .001). No main-effect significant group differences were found for any variable after controlling for these variables. However, sex differences were demonstrated for the neuropsychological variables in copying (P > .001), nonverbal reasoning (P= .001), manual dexterity (P= .001), and inhibitory capacity (P= .006), all favoring girls. Birth following IVF-assisted conception did not increase the risk of intellectual, neuropsychological, or behavioral deficit in LPT preschoolers. As shown in earlier gestational-age participants, girls have selective advantages. These findings should be reassuring for parents who conceive through IVF and deliver infants 1-3 weeks before term gestational age. Future study of these children at elementary school age may detect subtle impairments not yet apparent at age 3years.

TOWARDS THE RATIONALIZATION OF ANTHROPOMORPHIC ROBOT HAND DESIGN: EXTRACTING KNOWLEDGE FROM CONSTRAINED HUMAN MANUAL DEXTERITY TESTING

In this work, we take a new approach to the determination of the quantified contribution of various attributes of the human hand to its dexterity, with the aim of transposing this knowledge into supportive guidelines for the design of anthropomorphic robotic and prosthetic hands. We have carried out a number of standard dexterity tests on normal human subjects with various physical constraints applied to selected attributes of their hands, and have analyzed the results of the tests to extract knowledge on the quantified contribution of each attribute to overall manual dexterity. This knowledge is particularly significant in cases where it is important to optimize the trade-off between dexterity and complexity in the design of artificial hands. The data collection was made over 35 h of direct experimentation involving 40 volunteers during two separate runs, and the results represent empirically-derived upper limits on the achievable performance of humanoid robot hands having the specified deficiencies. We discuss the implications of our results in the context of a minimal anthropomorphic dexterous hand, which would incorporate the lowest possible number of degrees of freedom and other attributes while still retaining an acceptable level of dexterity. We end the paper with a suggestion on how the general approach presented herein could be extended to provide a platform for the quantification of the dexterity of anthropomorphic artificial hands.

Interactions between Cold Ambient Temperature and Older Age on Haptic Acuity and Manual Performance

The impact of exposure to cold on individuals' motor skills demands a deeper understanding of the ways in which cold weather influences psychomotor and haptic performance. In this study, various facets of psychomotor performance were evaluated in order to determine the impacts of ambient cold exposure on older persons. Healthy younger and older persons performed a battery of haptic psychomotor tests at room (23° C) and cold (1° C) ambient temperatures. The results indicate that older individuals do not perform as well as younger persons across the battery of tests, with cold temperature further degrading their performance in dexterity tasks (in, for example, Minnesota Manual Dexterity test placing: F [1, 16] = 10.23, p < .01) and peak precision grip force generation (F [1, 16] = 18.97, p < .01). The results suggest that cold weather may have an impact on the occupations older persons are able to perform during the winter months.