Tactile Measures Research Articles

Tactile measures in the structure of intelligence.

This study investigated the relationship of tactile abilities within the framework of a hierarchical structure of mental abilities. Data were analysed from 229 participants who were administered tactile measures from the Dean-Woodcock Sensory Motor Battery along with a battery of conormed cognitive measures representative of the Cattell-Horn-Carroll (CHC) model of intelligence. Multiple measures of tactile performance were used including Palm Writing and Object Identification, and each measure included a lateralized measure (i.e., right/left). Factor analytic results suggest tactile measures have a significant relationship with measures of cognitive ability. In this study, tactile measures involving object identification were more related to cognitive measures of visual processing-speed and overall processing speed; whereas, tactile measures involving the recognition of numbers written on the palm of the hand produced high loadings on a separate factor. Results from this study suggest different tactile measures may differentially load on cognitive factors depending on the common processing demands of the tactile and cognitive measures. Suggestions for differentiating common processing demands between tactile and cognitive measures are discussed.

Poster 94: Predictive Value of the Disorders of Consciousness Scale: Overall Neurobehavioral Change and Change by Modalities

Objectives: To examine the predictive validity of neurobehavioral change derived from the Disorders of Consciousness Scale (DOCS). Design: Prospective observational predictive validity study. Setting: Inpatient rehabilitation hospitals and postrehabilitation residence. Participants: 113 persons with a mean age of 38±17.8 who were unconscious for >28 days consecutively after severe BI; 73% (83/113) with traumatic BI and 27% (30/113) with other BI. Interventions: Not applicable. Main Outcome Measures: The measures derived from the DOCS reflect changes in overall neurobehavioral functioning and changes in functioning according to modalities. The outcomes include return to consciousness 4, 8 and 12 months after severe brain injury (BI). Results: When controlling for injury type, the DOCS average as well as DOCS change between the first and second DOCS (DOCS1-2), first and fifth DOCS (DOCS1-5) and first and last DOCS (DOCStotalchg) significantly (P ≤.05) contributed to predicting recovery and lack of recovery of consciousness at 4, 8 and/or 12 months after injury. DOCS1-5 manifested the most balanced accuracy in predictions where predicting recovery of consciousness is accurate 87% of the time and predicting lack of recovery of consciousness is accurate 88% of the time. Modality measures derived from the DOCS being examined, at time of writing this abstract, include sensory, partial cognitive, higher cognitive, auditory, tactile and visual measures. Conclusions: For persons with prolonged disorders of consciousness, the findings indicate that evidence based prognostication for individual patients are possible. Modality measures may enhance accuracy. The implications for research are that the DOCS can be used as a meaningful, reliable and valid primary outcome to measure treatment effects in clinical trials. The evidence indicates further that DOCS measures merit inclusion in future research aiming to develop multivariate prognostication models.

The effects of age on sensory thresholds and temporal gap detection in hearing, vision, and touch

Differences in sensory function between young (n = 42, 18-31 years old) and older (n = 137, 60-88 years old) adults were examined for auditory, visual, and tactile measures of threshold sensitivity and temporal acuity (gap-detection threshold). For all but one of the psychophysical measures (visual gap detection), multiple measures were obtained at different stimulus frequencies for each modality and task. This resulted in a total of 14 dependent measures, each based on four to six adaptive psychophysical estimates of 75% correct performance. In addition, all participants completed the Wechsler Adult Intelligence Scale (Wechsler, 1997). Mean data confirmed previously observed differences in performance between young and older adults for 13 of the 14 dependent measures (all but visual threshold at a flicker frequency of 4 Hz). Correlational and principal-components factor analyses performed on the data from the 137 older adults were generally consistent with task and modality independence of the psychophysical measures.

Perceived self-orientation in allocentric and egocentric space: Effects of visual and physical tilt on saccadic and tactile measures

Do physical tilt and tilt of the visual environment affect perception of allocentric and egocentric space? We addressed this question using two perceptual-motor tasks: alignment of a tactile rod (ROD) and saccadic eye movements (EM). Nine participants indicated the vertical axis of their heads (egocentric task), as well as the direction of gravity (allocentric task). Head orientation (± 60° and 0°) and visual environment orientation (± 120°, ± 60° and 0°) were independently manipulated in the fronto-planar roll plane. ROD and EM estimates of both allocentric and egocentric reference directions varied with head and room orientation. Physical tilt dominated allocentric estimates in the dark where overestimates of physical tilt were noted up to 11° using both measures. Allocentric ROD and EM estimates were significantly correlated across all head orientations ( r = .70, p < .01) but only when upright for egocentric estimates ( r = .38, p < .01). The relative contributions of the visual environment, gravity's direction and long-body axis to the estimation of allocentric and egocentric directions were determined by vector modeling. This modeling found that vision determined about 14% of the allocentric ROD and EM estimates, that the long-axis body reference played no discernible role, and that the largest factor was gravity, the effective direction of which was non-veridical. For egocentric estimates, vision contributed about 3% with the largest factor being the body reference. We conclude that perception of allocentric and egocentric space is likely influenced by multiple senses that define common egocentric and allocentric frames of reference accessible for saccadic and tactile estimates of perceived self-orientation.

Neuropsychological and Information Processing Performance and Its Relationship to White Matter Changes Following Moderate and Severe Traumatic Brain Injury: A Preliminary Study

Reductions in information processing speed have frequently been reported following moderate and severe traumatic brain injuries (TBIs), consistent with the effects of diffuse white matter damage. Although the corpus callosum (CC) is a common site for diffuse damage following TBI, the effects of this damage on information processing speed have not been adequately examined. This study assessed a TBI group and a matched control group on tests of attention, memory, fluency, and set shifting ability, together with reaction time (RT) tasks requiring the inter- and intrahemispheric processing of visual and tactile information. The RT tasks were designed to target the cognitive functions that are likely to be affected by diffuse white matter damage, including damage to the CC. The TBI group demonstrated deficits in verbal and visual fluency and verbal memory. They were also slower on the visual and tactile RT tasks, were more affected by task complexity, and slower on RT tasks requiring the interhemispheric transfer of information. In fact, one of the interhemispheric tactile RT tasks proved to be the most discriminating of all the cognitive and RT measures. MRIs completed on a subset of TBI participants indicated that the mean CC measurements were 5% to 19% smaller than a normative control group, with the most atrophied areas being the isthmus and anterior midbody. Although white matter atrophy was moderately related to visual and tactile RT performance, and total hippocampal volume related to memory performance, CC area was not related to many of the tasks that were designed to tap interhemispheric processing. None of the standard cognitive tests correlated with outcome in the TBI group, but 1 of the tactile RT measures was significantly related to 2 measures of outcome.

From good senses to good sense: A link between tactile information processing and intelligence

Since the 1970s there has been an reemerging interest in Galton's (1883) senses-intelligence hypothesis. The essence of this hypothesis is the conceptual link between fine-tuned sensory functioning and superior intellectual ability. Several studies have investigated the sensory-cognitive link within auditory and visual modalities. In this study, the intersystemic relationship between sensory and cognitive functioning was extended to the tactile modality by examining the associations between three measures of tactile information processing and intelligence in a heterogeneous sample of middle-aged adults (N = 179; age range = 30–51). Two of the three tactile tasks measured discrimination ability (i.e., roughness discrimination and part-whole matching), whereas the third task measured tactile pressure sensitivity. Results from a series of analyses indicate that sensory measures from the tactile modality are at least as highly correlated with intellectual ability ( r = .18 to .33) as measures of auditory ( r = .15) or visual ( r = .20) acuity. All together, the three tactile measures accounted for 20.8% of the total variance in intelligence. The two tactile discrimination measures were found to be better predictors of intelligence than measures of simple sensory acuity.

Tactile defensiveness and stereotyped behaviors.

This study explores the constructs of stereotyped behaviors (e.g., repetitive motor patterns, object manipulations, behavioral rigidities) and tactile defensiveness as relevant to occupational therapy theory and practice and attempts to test their purported relationships in children with developmental disabilities. Twenty-eight children with developmental disabilities and autism were assessed on eight factors of stereotyped behavior via a questionnaire and by four measures of tactile defensiveness. The subjects' scores from the questionnaire were correlated with their scores on the tactile defensiveness measures to see what, if any, relationship among these behaviors exists. Significant relationships emerged from the data, indicating that subjects with higher levels of tactile defensiveness were also more likely to evidence rigid or inflexible behaviors, repetitive verbalizations, visual stereotypes, and abnormal focused affections that are often associated with autism. No significant association was found between motor and object stereotypes and tactile defensiveness. These relationships could not be explained solely by maturational factors. The results suggest that clinicians should include observations of stereotyped behaviors, particularly behavioral rigidities, in conjunction with assessments of sensory defensiveness because these are related phenomena that may pose unique challenges for children with developmental disabilities and autism. Further study is needed to determine the causal mechanisms responsible for these relationships.

Aging and Postural Stability:

PURPOSE: The purpose of this study was to examine the relationships between the toe's pressure and tactile sense and measures of postural stability. SUBJECTS: The subjects of the study were 21 healthy volunteers who were divided into two age groups: young group (mean 21.0 ± 1.6 years): 7 males and 6 females, elderly group (mean 71.4 ± 2.8 years): 4 males and 4 females. METHODS AND MATERIALS: First experiment (balance test): The instrument for measuring standing balance was a stabilometer. A computer program built into the device provides information on the subject's stance balance through calculation of two variables: (1) Body sway index (SI: mm), and (2) Foot pressure (%BW/cm²). The subjects were asked to stand as motionless as possible for 20 seconds. The same test was repeated with the subject's eyes closed. Second experiment (tactile sense test): utilized a new system which was developed to measure tactile-proprioceptive sensation. The tactile threshold value was measured with the subject seated in a ...

Tactile and auditory measures of modulation resolution

Limited signals derived from speech can provide effective supplements to speechreading. For a single-band speech envelope that is used to modulate a 200-Hz tone, the benefit to speechreading is, however, greater with auditory than tactile presentation. Is this due to differences between hearing and touch in the psychophysical ability to perceive amplitude modulation changes? Experiments are being conducted to assess amplitude modulation discrimination as a function of reference modulation depth (m=0 to 1) and modulation frequency (fm=5 or 50 Hz). Carrier frequency is fixed at 200 Hz and stimulus presentation is via headphone for audition and a minishaker for taction. Preliminary results indicate that, on average, auditory thresholds for Δm are roughly 6 dB more sensitive than tactile thresholds. These results extend those previously available in the literature by considering cases of nonzero reference values for m, which may be particularly relevant to the information that is conveyed in the single-band speech envelope. [Work supported by NIDCD.]

Motor Proficiency and Neuropsychoiogical Function in Depressed Adolescent Inpatients: A Pilot Inwestigation

This investigation explored the belief that physical activity therapy has a neurological value as part of the total treatment of mental patients. Twenty-two adolescents hospitalized with depression were administered a battery of diagnostic tests. Relationships among the Braininks-Oseretsky Motor Proficiency test (12 subtest scores) and the Luria-Nebraska Neuropsychological Battery (14 subtest scores) were examined. All patients were nonmedicated and on a neurotransmitter controUed diet for 48 hours prior to testing. Results indicate that certain forms of motor performance can be predicted from measures indicative of both structure and fonction of brain behavior. The multiple R2 ranged from .80 to .06, with variance in balance, bilateral coordination, and fine motor skills being predicted from the receptive speech, tactile, right hemisphere, left hemisphere, expressive speech, motor, and rhythm measures of brain behavior. When explaining neuropsychological battery scores from motor proficiency scores, the R2 ranged from .65 to .28, with intelligence and expressive speech being predicted from the gross motor composite, upper limb speed, and dexterity, balance, and fine motor composite scores, respectively.

Perceived velocity as a function of reference mark density.

The effect on apparent visual speed of varying the density of stationary reference marks evenly distributed along the path of motion of a point of light was measured using tactile comparison motion. The sensitivity of the tactile method of measuring visual speed was supported by the finding that the tactile measures increased with each increase in physical speed of the point of light, other factors held constant. This procedure was applied in two experiments to visual displays in which the physical speed, extent of motion, and number and density of reference marks was varied. Only reference mark density, in addition to physical speed, was found to be a signficant (and robust) factor in determining perceived speed. The effect of reference mark density is explained in terms of the increasing contribution of relative motion cues to the perception of visual speed as a funciton of the average separation (or average adjacency) of the moving point from surrounding reference marks.

The Use of Verbal and Tactile Comfort to Alleviate Distress in Young Hospitalized Children

AbstractThis exploratory study was designed to observe distressed children's responses to verbal and tactile comfort measures. A convenience sample of 63 children between 3 days and 44 months old was drawn from a pediatric unit of a large midwestern hospital. On a random basis, one group of children received verbal, comfort measures for 5 minutes or until they quieted, whichever came first. At the end of 5 minutes, tactile comfort was added if the children were still distressed. The other group received simultaneous tactile‐verbal comfort from the beginning. One hundred interventions were carried out on the 63 children. Forty interventions were initially verbal and 60 were tactile‐verbal. Among the verbal group, 7 of the interventions were successful in quieting the children as compared to 53 successes of 60 interventions in the tactile‐verbal group. This was a highly significant difference. Verbal interventions were more successful for children over 1 year old and tactile comfort was least effective with children in the 13 to 18 month age group. No differences were noted in terms of sex, presence of equipment including restraints, diagnosis, and recency of last feeding.

Electrotactile Sensitivity under Different Intensities of Simultaneous Auditory Stimulation

Direct electrical stimulation of the skin can arouse sensations similar to those from brief mechanical contact. In this study, tactile thresholds were obtained with brief pulses of direct current, under four different intensities of simultaneous broad-band continuous noise ranging from 54 dB (estimated ambient noise) to 92 dB SL. Stimulation site was the right thenar eminence, the palmar base of the thumb. Electrical touch stimuli were 100-msec-long trains of 0.5-msec anodal rectangular pulses, delivered by constant current stimulator at a pulse repetition rate of 100 pps. Thresholds were obtained from 12 subjects by means of a two-alternative forced-choice procedure. Stimulus intensity was varied by changing pulse amplitude alone. Electrotactile thresholds were highest under moderately intense noise, 66 and 79 dB SL. The magnitude of the threshold shift was small, less than 1.0 (tactile) dB, and statistically significant. Thresholds were lowest at both extremes of the sound intensity range, 54 and 92 dB SL. Variability around threshold was greatest under moderate intensity noise, least under ambient noise, where tactile thresholds were lowest. Electrotactile intensity discrimination, as it presumably involves stimulation behind the receptor, should measure limits for the touch sense. ΔI/I was most acute where absolute thresholds were worst, under moderate noise intensity. Conservative estimates of ΔI/I using run length are at worst 0.05/with ambient noise, a value in line with vibratory tactile measures.