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PubMedDate not supplied

Using assistive technology adaptations to include students with learning disabilities in cooperative learning activities.

Cooperative learning (CL) is a common instructional arrangement that is used by classroom teachers to foster academic achievement and social acceptance of students with and without learning disabilities. Cooperative learning is appealing to classroom teachers because it can provide an opportunity for more instruction and feedback by peers than can be provided by teachers to individual students who require extra assistance. Recent studies suggest that students with LD may need adaptations during cooperative learning activities. The use of assistive technology adaptations may be necessary to help some students with LD compensate for their specific learning difficulties so that they can engage more readily in cooperative learning activities. A process for integrating technology adaptations into cooperative learning activities is discussed in terms of three components: selecting adaptations, monitoring the use of the adaptations during cooperative learning activities, and evaluating the adaptations' effectiveness. The article concludes with comments regarding barriers to and support systems for technology integration, technology and effective instructional practices, and the need to consider technology adaptations for students who have learning disabilities.

Cooperative Behavior↗

PubMed2006

Sensitivity of a computer adaptive assessment for measuring functional mobility changes in children enrolled in a community fitness programme.

OBJECTIVE: To examine the relative sensitivity to detect functional mobility changes with a full-length parent questionnaire compared with a computerized adaptive testing version of the questionnaire after a 16-week group fitness programme. DESIGN: Prospective, pre- and posttest study with a 16-week group fitness intervention. SETTING: Three community-based fitness centres. SUBJECTS: Convenience sample of children (n = 28) with physical or developmental disabilities. INTERVENTIONS: A 16-week group exercise programme held twice a week in a community setting. MAIN MEASURES: A full-length (161 items) paper version of a mobility parent questionnaire based on the Pediatric Evaluation of Disability Inventory, but expanded to include expected skills of children up to 15 years old was compared with a 15-item computer adaptive testing version. Both measures were administered at pre- and posttest intervals. RESULTS: Both the full-length Pediatric Evaluation of Disability Inventory and the 15-item computer adaptive testing version detected significant changes between pre- and posttest scores, had large effect sizes, and standardized response means, with a modest decrease in the computer adaptive test as compared with the 161-item paper version. Correlations between the computer adaptive and paper formats across pre- and posttest scores ranged from r = 0.76 to 0.86. CONCLUSIONS: Both functional mobility test versions were able to detect positive functional changes at the end of the intervention period. Greater variability in score estimates was generated by the computerized adaptive testing version, which led to a relative reduction in sensitivity as defined by the standardized response mean. Extreme scores were generally more difficult for the computer adaptive format to estimate with as much accuracy as scores in the mid-range of the scale. However, the reduction in accuracy and sensitivity, which did not influence the group effect results in this study, is counterbalanced by the large reduction in testing burden.

Adolescent↗

PubMed1980

Adaptive regression of two types.

Adaptive regression is considered to be of two types: a relatively uncommunicable private type and a relatively communicable public type. Private adaptive regression was operationalized by hypnotic suggestibility and by a questionnaire. Public adaptive regression was operationalized by two measures of esthetic sensitivity. It was hypothesized that the psychodynamics of the two types are as follows: Hypothesis 1: Private adaptive regression involves engaging in primary process because of secondary process motivation. Hypothesis 2: Public adaptive regression involves engaging in primary process because of secondary process motivation. Hypothesis 3: Public adaptive regression involves secondary process shaping of primary process to a greater extent than does private adaptive regression. Measures of engaging in primary process were derived from inkblot responses. Hypotheses 1 and 3 were supported: Hypothesis 2 was not.

Journal Article↗

PubMed2007

Early adaptations to training: upregulation of alpha-myosin heavy chain gene expression.

UNLABELLED: Chronic exercise induces adaptations that increase the functional capacity of the cardiovascular system. Aside from ventricular growth, these adaptations include a shift in the MHC isoenzyme pattern to enhance ventricular contractility. It is unclear whether adaptations by the contractile elements are an early event and specific to exercise, or whether they progress as a function of cardiac growth. Examining early adaptations to training is also important because it is during this period when the greatest imbalance between increased demand and functional capacity exists, and it is likely that the mechanisms responsible for propagating changes in the myocardial phenotype are most active. PURPOSE: To determine whether changes in left ventricular (LV) contractile elements are an early adaptation to chronic exercise. METHODS: Rats were randomly assigned to sedentary control or exercise training groups for 1 or 10 wk of training. After training, the LV was analyzed for protein by Western blot or mRNA by Northern and real-time QRT-PCR analysis. RESULTS: Plantaris cytochrome oxidase activity was significantly (P < 0.05) increased by 1 wk (+28%) or 10 wk (+32%) of training. Training significantly increased LV myofibrillar alpha-MHC protein and alpha-MHC-mRNA after both training periods. No changes in myofibrillar beta-MHC protein or beta-MHC-mRNA were observed. After 1 wk of training, LV skeletal alpha-actin-mRNA was significantly increased, whereas no changes were found for ANF, glyceraldehyde dehydrogenase, or cytochrome oxidase IV. Gel mobility shift analysis determined that YY1 DNA binding was significantly decreased in LV extracts from trained animals, although no change in YY1-mRNA expression was observed. CONCLUSIONS: Increased myofibrillar alpha-MHC protein and alpha-MHC-mRNA expression are early events in the adaptation to chronic exercise and occur before significant cardiac growth. These adaptations enhance myocardial contractility and permit increases in maximal cardiac output during heavy exercise.

Animals↗

PubMed2002

Decoupled stochastic parallel gradient descent optimization for adaptive optics: integrated approach for wave-front sensor information fusion.

A new adaptive wave-front control technique and system architectures that offer fast adaptation convergence even for high-resolution adaptive optics is described. This technique is referred to as decoupled stochastic parallel gradient descent (D-SPGD). D-SPGD is based on stochastic parallel gradient descent optimization of performance metrics that depend on wave-front sensor data. The fast convergence rate is achieved through partial decoupling of the adaptive system's control channels by incorporating spatially distributed information from a wave-front sensor into the model-free optimization technique. D-SPGD wave-front phase control can be applied to a general class of adaptive optical systems. The efficiency of this approach is analyzed numerically by considering compensation of atmospheric-turbulence-induced phase distortions with use of both low-resolution (127 control channels) and high-resolution (256 x 256 control channels) adaptive systems. Results demonstrate that phase distortion compensation can be achieved during only 10-20 iterations. The efficiency of adaptive wave-front correction with D-SPGD is practically independent of system resolution.

Journal Article↗

PubMed2006

Questioning complacency: climate change impacts, vulnerability, and adaptation in Norway.

Most European assessments of climate change impacts have been carried out on sectors and ecosystems, providing a narrow understanding of what climate change really means for society. Furthermore, the main focus has been on technological adaptations, with less attention paid to the process of climate change adaptation. In this article, we present and analyze findings from recent studies on climate change impacts, vulnerability, and adaptation in Norway, with the aim of identifying the wider social impacts of climate change. Three main lessons can be drawn. First, the potential thresholds and indirect effects may be more important than the direct, sectoral effects. Second, highly sensitive sectors, regions, and communities combine with differential social vulnerability to create both winners and losers. Third, high national levels of adaptive capacity mask the barriers and constraints to adaptation, particularly among those who are most vulnerable to climate change. Based on these results, we question complacency in Norway and other European countries regarding climate change impacts and adaptation. We argue that greater attention needs to be placed on the social context of climate change impacts and on the processes shaping vulnerability and adaptation.

Climate↗

PubMed2003

Detection of coronary calcifications: feasibility of dose reduction with a body weight-adapted examination protocol.

OBJECTIVE: The purpose of this study was to assess the applicability of individual body weight-adapted tube current time settings in multidetector CT for detection of coronary calcifications and to evaluate the effect of reducing the radiation dose on the coronary calcium score. SUBJECTS AND METHODS. One hundred patients underwent retrospectively ECG-gated MDCT for detection of coronary calcifications. First, fixed tube current time settings were used in 50 patients. Second, image noise corresponding to body weight-adapted tube current time settings was added to these images. Finally, body weight-adapted tube current time settings were applied to another 50 patients. For each patient group, the radiation dose was calculated. Coronary calcium scores were compared for the patient groups with the fixed tube current time settings with and without artificially added image noise. In all image series, image noise was assessed by a region-of-interest methodology. Image noise was analyzed using a regression analysis. RESULTS: The effective radiation dose was reduced by 11.6% for men and 24.8% for women using the body weight-adapted tube current time settings. There were no statistically significant changes in the coronary calcium score after the addition of artificial image noise (p = 0.84). Adaptation of the tube current time settings did not lead to a relevant increase in image noise. The radiation doses for the plotted noise-to-body weight (slope, 0.081) and noise-to-body mass index (slope, 0.378) ratios for the standard protocol proved relatively high for patients of lower weight. An improved noise-to-body weight (slope, 0.054) and noise-to-body mass index (slope, 0.190) ratio was achieved by application of the body weight-adapted tube current time settings, resulting in nearly constant image noise related to body weight. CONCLUSION: Individual body weight-adapted current time settings are applicable for coronary calcium scoring without a change of the coronary calcium score or relevant increase of the image noise.

Body Mass Index↗

PubMed1993

Loudness adaptation in children.

Simple loudness adaptation was measured for a steady tone presented alone at 10 dB SL; contralaterally induced adaptation was measured for a steady tone in one ear accompanied by an intermittent tone in the contralateral ear; ipsilaterally induced adaptation was measured for a tone increased intermittently by 15 dB. The method of successive magnitude estimation revealed no differences between 12 adults and 36 children from 9 to 14 years of age in the amounts of adaptation over a 3-min exposure. A second set of experiments with a new group of 20 adults and 20 children used a Békésy tracking procedure to reach similar results. Unlike Kärjä [Acta Oto-Laryngol 1968; (suppl)241:1-56], who found significant adaptation in only 5 of 29 children and much adaptation in most adults, we found considerable adaptation in children as well as in adults.

Acoustic Stimulation↗

PubMed2002

Evaluation of an adaptive, directional-microphone hearing aid.

The effectiveness of adaptive directional processing for improvement of speech recognition in comparison to non-adaptive directional and omni-directional processing was examined across four listening environments intended to simulate those found in the real world. The test environment was a single, moderately reverberant room with four loudspeaker configurations: three with fixed discrete noise source positions and one with a single panning noise source. Sentence materials from the Hearing in Noise Test (HINT) and Connected Speech Test (CST) were selected as test materials. Speech recognition across all listening conditions was evaluated for 20 listeners fitted binaurally with Phonak Claro behind-the-ear (BTE) style hearing aids. Results indicated improved speech recognition performance with adaptive and non-adaptive directional processing over that measured with the omnidirectional processing across all four listening conditions. While the magnitudes of directional benefit provided to subjects listening in adaptive and fixed directional modes were similar in some listening environments, a significant speech recognition advantage was measured for the adaptive mode in specific conditions. The advantage for adaptive over fixed directional processing was most prominent when a competing noise was presented from the listener's sides (both fixed and panning noise conditions), and was partially predictable from electroacoustically measured directional pattern data.

Audiometry, Pure-Tone↗

PubMed2004

Checkpoint adaptation and recovery: back with Polo after the break.

S. cerevisiae cells that are unable to repair a double strand break ultimately escape the DNA damage checkpoint arrest and enter mitosis. This process called 'adaptation' depends on functional Cdc5, a Polo-like kinase, and was long thought to be limited to single-cell organisms. However, the recent finding that Xenopus extracts can adapt to a long-lasting stall in DNA replication indicates that checkpoint adaptation does also occur in multicellular organisms. Interestingly, the Xenopus Polo-like kinase (Plx1) plays an important role in this adaptation. To add to this, data from our laboratory have shown that the human Polo-like kinase (Plk1) is also required for cell cycle reentry following a DNA damage-induced arrest. But here, Plk1 was shown to be required for bona-fide checkpoint recovery, rather than adaptation. That is, Plk1 is required to restart the cell cycle once all of the damage is repaired and checkpoint signaling is turned off. While the target of Plx1 during adaptation is a component of the checkpoint machinery (Claspin), the target of Plk1 during recovery turns out to be a mitotic regulator (Wee1). Here, we discuss some of the remarkable similarities and subtle differences in the molecular mechanisms that control checkpoint adaptation and recovery, and the role of Polo-like kinases therein.

Adaptor Proteins, Signal Transducing↗

PubMedDate not supplied

Adaptive strategies of mothers with children with attention deficit hyperactivity disorder: enfolding and unfolding occupations.

OBJECTIVE: To describe adaptive strategies of time use among mothers with children with attention deficit hyperactivity disorder (ADHD) and, in particular, the adaptive strategies of unfolding occupations that were commonly used by these mothers. METHOD: In-depth interviews were conducted with 17 families with children with ADHD. Parents were asked to describe their family's daily schedule, routines, and how occupations were performed. Data were analyzed using the grounded theory approach. FINDINGS: Mothers used three adaptive strategies: enfolding occupations, temporal unfolding of occupations, and unfolding occupations by inclusion. Enfolding occupations means performing more than one occupation at a time. Unfolding occupations means taking chunks of activities or occupations out of previously established sequences of enfolded occupations to be performed at a different time (temporal unfolding) or by a different person (unfolding by inclusion). The child's special needs and the availability of financial and human resources influenced the selection of adaptive strategy. Using these adaptive strategies enabled the mothers to care for their children. However, using enfolding or temporal unfolding meant that mothers had less time for other occupations. CONCLUSION: The benefits and limitations of the adaptive strategies of enfolding and unfolding occupations suggest a need to study time use in different contexts. Before suggesting use of these adaptive strategies by parents of children with special needs, therapists need to be aware of the family's financial and human resources.

Adult↗

PubMed1976

[Altitude adaptation. Part III. Altitude acclimatization as a problem of human biology (II. Morphology, physiology, biochemistry)].

The physiological mechanisms of adaptation will be reported. In a primary step of adaptation, the body reacts with immediate response, which already leads to a first classification: whether or not altitude will be tolerated by an individual. More steady biological processes follow with the same intention of balancing oxygen deficiency. They may be successful and acclimatization is possible, or they do not achieve the necessary level, i.e. that consequently developing pathological conditions of different severity lead to a next assortation of individuals with insufficient adaptability. The first state of lability can be compensated, or the intolerance will make a further stay in high altitudes impossible. No parameters exist which could allow a prognosis as to what kind of individuals will tolerate altitude or not. A different pattern of biological reaction is seen in permanent inhabitants of high altitudes who have been residing there for generations and haven't experienced conditions other than those of their special altitude in their individual lives. While ascending to higher altitudes, permanent residents also have to undergo new adaptation, as well as when descending to lower altitudes. Returning to their native environment requires reacclimatization. The mechanisms of adaptation on the organ level will be reviewed, as well as on the fluid and cellular level. All those functional and morphological mechanisms of adaptation to oxygen deficiency in high altitudes tend to maintain optimal equilibrium. Maladaptation may result. Expected genetically determined physiological alterations of adaptational value in permanent residents, which could have manifested themselves by way of "soft" selection and change of gene frequency in those high altitude populations, will be discussed. Genetical determination in such physiological parameters does not seem probable, although some pecularities such as the "blunted response" ventilation, the higher Bohr-Effect in Quenchua etc. might be interpreted in this direction.

Acclimatization↗

PubMed2001

Absence of Crabtree effect in human melanoma cells adapted to growth at low pH: reversal by respiratory inhibitors.

Because many tumors are acidic and hypoxic relative to normal tissues, glycolysis and oxygen consumption were investigated in early-passage human melanoma cells adapted to growth at pH 6.7. In the absence of glucose, the basal rate of oxygen consumption in low pH-adapted cells was 75% of that in cells grown at pH 7.3. The rate of lactic acid production in low pH-adapted cells was increased 4-fold by exposure to 16.7 mM glucose compared with a 10-fold increase in cells grown at pH 7.3. Furthermore, in low pH-adapted cells the rate of oxygen consumption was stimulated by the addition of glucose in contrast to the inhibition of oxygen consumption by elevated glucose in cells grown at pH 7.3 (i.e., the Crabtree effect). Both low pH-adapted cells and cells grown at pH 7.3 exposed to glucose plus 0.35 mM meta-iodo-benzylguanidine (MIBG), an inhibitor of mitochondrial respiration, had oxygen consumption reduced by approximately 60% and lactic acid production increased by approximately 65% relative to glucose alone. Although adaptation to growth at low pH was associated with a loss of the Crabtree effect and a higher ratio of oxygen consumption to lactic acid production, the rate of glycolysis was the same in both growth conditions in the presence of 0.1 mM dinitrophenol, an uncoupler of ATP synthesis. This indicates that the glycolytic capacity of low pH-adapted cells remains unchanged. Therefore, tumor acute acidification and oxygenation can be achieved by exposure to hyperglycemia combined with MIBG to improve therapeutic response.

3-Iodobenzylguanidine↗

PubMed2002

Adaptive multiscale principal components analysis for online monitoring of wastewater treatment.

Fault detection and isolation (FDI) are important steps in the monitoring and supervision of industrial processes. Biological wastewater treatment (WWT) plants are difficult to model, and hence to monitor, because of the complexity of the biological reactions and because plant influent and disturbances are highly variable and/or unmeasured. Multivariate statistical models have been developed for a wide variety of situations over the past few decades, proving successful in many applications. In this paper we develop a new monitoring algorithm based on Principal Components Analysis (PCA). It can be seen equivalently as making Multiscale PCA (MSPCA) adaptive, or as a multiscale decomposition of adaptive PCA. Adaptive Multiscale PCA (AdMSPCA) exploits the changing multivariate relationships between variables at different time-scales. Adaptation of scale PCA models over time permits them to follow the evolution of the process, inputs or disturbances. Performance of AdMSPCA and adaptive PCA on a real WWT data set compared and contrasted. The most significant difference observed was the ability of AdMSPCA to adapt to a much wider range of changes. This was mainly due to the flexibility afforded by allowing each scale model to adapt whenever it did not signal an abnormal event at that scale. Relative detection speeds were examined only summarily, but seemed to depend on the characteristics of the faults/disturbances. The results of the algorithms were similar for sudden changes, but AdMSPCA appeared more sensitive to slower changes.

Algorithms↗

PubMed2003

Electromyographic evaluation of the adductor pollicis muscle of elderly patients carriers of removable partial prosthesis when using acrylic devices adapted to the handle of toothbrush.

The aim of this study was to evaluate the muscular activity of the adductor pollicis muscle, by electromyography, when using a device made of acrylic resin adapted to the handle of toothbrush. 10 patients of both sexes from the Clinic of Removable Partial Dentures of the Dental School--USP, with a mean age of 65 years, were selected. Electromyographic records were obtained with patients in clinical conditions of Initial Rest and under conditions of claw apprehension and dental brushing. The mean results obtained, in mV, were: sat men: 2.97 for rest (R); 11.55 for free closure (FC); 35.80 for strained closure (SC); 29.30 for simulated brushing (SB); 55.00 for brushing (B); 26.87 for simulated brushing with the device (SBA); 69.70 for brushing with the device (BA); 3.72 for post exercise rest (PR). Standing: 2.27 for rest (R); 13.92 for free closure (FC); 45.85 for strained closure (SC); 28.40 for simulated brushing (SB); 72.07 for brushing with the device (BA); 1.42 for postexercise rest (PR). Sat women: 9.78 for rest (R); 22.71 for free closure (FC); 41.48 for strained closure (SC); 26.45 for simulated brushing (SB); 52.78 for brushing (B); 17.00 for simulated brushing with the adapter (SBA); 42.38 for brushing with the adapter (BA); 14.40 for postexercise rest (PR). Standing: 5.26 for rest (R); 17.81 for free closure (FC); 46.55 for strained closure (SC); 40.61 for simulated brushing (SB); 61.71 for brushing (B); 26.08 for simulated brushing with the adapter (SBA); 54.06 for brushing with the adapter (BA); 3.46 for postexercise rest (PR). The adductor pollicis muscle showed a higher electromyographic activity, considered statistically similar to each other, in 3 clinical conditions analyzed: brushing (B), brushing with the adapter (BA) and strained closure (SC). The adductor pollicis muscle showed lower electromyographic activity, considered statistically similar, in 5 clinical conditions analyzed: simulated brushing (SB), simulated brushing with the adapter (SBA), free closure (FC), rest (R) and postexercise rest (PR).

Acrylic Resins↗

PubMed1990

[Ethnogenetics: adaptive structure of the gene pool of the mankind from the data on human polymorphic genetic markers].

The mean FST value as a characteristic of gene frequency changes in a random sample of polymorphic genes from population gene pool provides the best indirect estimation of selectively neutral level of genetic variability. The set of test criteria, including chi 2, F and t, can be used in order to compare F1 with F and subdivide gene sample into three subgroups, or classes of genes which are differing from each other by the degree of variation of allelic frequencies. These three classes comprise the adaptive structure of gene pool and consist of the genes which are, respectively, under stabilizing and differentiating selection pressures or neutral ones. Adaptive structures of gene pools of aboriginal human populations at the main 9 geographical regions of the World, taken together, reveal statistically significantly correlation with adaptive structure of the total gene pool of the Mankind. But the correlation is rather small and therefore, the adaptive structure of human gene pool reveals between adaptive structures, the highest is for the USSR and the lowest are for the East-Asiatic and Australian regions. The proportion of neutral to non-neutral genes is about 50% in the average, with the range of variation 40-60% in different regions. But none of the polymorphic genes so far studied reveals constant neutrality in all regional conditions of environment and at different times of evolution history of human gene pool. Its adaptive structure underwent essential transformation from the Palaeolithic till the Postpalaeolithic times, but nevertheless, among the main features of contemporary adaptive structure of human gene pool, those predominate which are of the Palaeolithic origin.

Alleles↗

PubMed1987

Adaptation of mechanoelectrical transduction in hair cells of the bullfrog's sacculus.

Adaptation in a vestibular organ, the bullfrog's sacculus, was studied in vivo and in vitro. In the in vivo experiments, the discharge of primary saccular neurons and the extracellular response of saccular hair cells were recorded during steps of linear acceleration. The saccular neurons responded at the onset of the acceleration steps, then adapted fully within 10-50 msec. The extracellular (microphonic) response of the hair cells adapted with a similar time course, indicating that the primary sources of the neural adaptation are peripheral to the afferent synapse--in the hair cell, its mechanical inputs, or both. Evidence for hair cell adaptation was provided by 2 in vitro preparations: after excising the sacculus and removing the accessory structures, we recorded either the extracellular hair cell response to displacement of the otolithic membrane or the intracellular hair cell response to hair bundle displacement. In both cases the response to a step stimulus adapted. The adaptation involved a shift in the displacement-response curve along the displacement axis, so that the cell's operating point was reset toward the static position of its hair bundle. This displacement shift occurred in response to both depolarizing and hyperpolarizing stimuli. Its time course varied among cells, from tens to hundreds of milliseconds, and also varied with the concentration of Ca2+ bathing the apical surfaces of the hair cells. Voltage-clamp experiments suggested that the displacement shift does not depend simply on ion entry through the hair cell's transduction channels and can occur at a fixed membrane potential. The possible role of the displacement-shift process in the function of the frog's sacculus as a very sensitive vibration detector is discussed.

Animals↗

PubMed1986

The Glenn A. Fry award lecture: adaptive regulation of accommodative vergence and vergence accommodation.

The tonic resting level of accommodation, measured with an objective infrared optometer in an open-loop state (pinhole pupil or empty field), was increased by more than 1.75 D from baseline measures of resting focus after adapting monocularly for 1 min to a 2 D minus lens. The accommodative aftereffect disappeared in darkness, but returned when a visible stimulus reappeared in the open-loop state. Stimulation of disparity vergence with 10 delta, while accommodation was in an open-loop state, also increased the resting focus of accommodation. Similarly, the tonic resting level of vergence became more esophoric after adapting for less than 1 min to base-out prism or to a minus lens presented while the vergence loop was opened. The effects of tonic accommodation on accommodative vergence and the effects of tonic vergence on vergence accommodation were investigated with the temporal frequency responses of the AC/A and CA/C ratios to sinusoidal variations in blur (2 D) and disparity (10 delta), respectively. Accommodative vergence was unresponsive to low temporal frequency sinusoidal variations in blur (less than 0.1 Hz). Similarly, vergence accommodation was unresponsive to low temporal frequency sinusoidal variations in disparity. However, accommodative vergence and vergence accommodation were responsive to higher temporal frequency stimuli (up to 0.5 Hz). When negative feedback to the stimulated system (accommodation or vergence) was cancelled electronically, the low temporal frequency response increased for the AC/A and CA/C ratios, respectively. There was also a nonlinear increase of both AC/A and CA/C ratios as stimulus amplitude increased. It is hypothesized that the nonlinearity resulted from limitations of adaptation to small stimuli. An inverse complementary relation is suggested between the amplitude of the AC/A ratio and adaptable tonic accommodation, and between the amplitude of the CA/C ratio and adaptable tonic vergence. This model predicts that in this complementary relation, adaptable tonic elements would sustain motor responses of accommodation and vergence that were initiated by phasic elements and cross-link interactions. It also predicts that the AC/A and CA/C ratios would decrease in time as dynamic control shifted from the phasic to the adaptable tonic control mechanisms of accommodation and vergence, respectively.

Accommodation, Ocular↗