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At least 541 records · Page 30Linked to original sources
PubMed2003

Bumetanide-induced enlargement of the intercellular space in the stria vascularis critically depends on Na+ transport.

The intercellular space in the stria vascularis (intrastrial space) is a closed space and isolated from both the endolymph and the perilymph in normal tissue. Loop diuretics such as bumetanide and furosemide cause an acute enlargement of the intrastrial space in association with a decline in the endocochlear potential. It is known that bumetanide inhibits the Na+-K+-2Cl- cotransporter, which is expressed abundantly in the basolateral membrane of marginal cells. We studied ionic mechanisms underlying the bumetanide-induced enlargement of the intrastrial space using perilymphatic perfusion in guinea pigs. Perilymphatic perfusion with artificial perilymph containing 100 microM bumetanide caused marked enlargement of the intrastrial space, as reported previously. Removal of K+ from the perilymph did not affect the bumetanide-induced enlargement, whereas removal of Na+ from the perilymph inhibited it almost completely. Perilymph containing 1 mM amiloride also inhibited the enlargement of the intrastrial space almost completely. These results indicate that perilymphatic Na+, but not K+, and amiloride-sensitive pathways are essential to the bumetanide-induced enlargement of the intrastrial space. Two possible pathways could yield these results. Na+ in the perilymph could enter the endolymph via Reissner's membrane or the basilar membrane; Na+ in the endolymph would then be taken up by marginal cells via the apical membrane and secreted into the intrastrial space by Na+-K+-ATPase in the basolateral membrane of them. Another, less likely possibility is that Na+ in the perilymph is transported into basal cells or fibrocytes in the spiral ligament, then into intermediate cells via gap junctions, and finally secreted into the intrastrial space via Na+-K+-ATPase of intermediate cells.

Amiloride↗
PubMed1998

Immune responses in space flight.

Space flight has been shown to have profound effects on immunological parameters of humans, monkeys and rodents. These studies have been carried out by a number of different laboratories. Among the parameters affected are leukocyte blastogenesis, natural killer cell activity, leukocyte subset distribution, cytokine production - including interferons and interleukins, and macrophage maturation and activity. These changes start to occur only after a few days space flight, and some changes continue throughout long-term space flight. Antibody responses have received only very limited study, and total antibody levels have been shown to be increased after long-term space flight. Several factors could be involved in inducing these changes. These factors could include microgravity, lack of load-bearing, stress, acceleration forces, and radiation. The mechanism(s) for space flight-induced changes in immune responses remain(s) to be established. Certainly, there can be direct effects of microgravity, or other factors, on cells that play a fundamental role in immune responses. However, it is now clear that there are interactions between the immune system and other physiological systems that could play a major role. For example, changes occurring in calcium use in the musculoskeletal system induced by microgravity or lack of use could have great impact on the immune system. Most of the changes in immune responses have been observed using samples taken immediately after return from space flight. However, there have been two recent studies that have used in-flight testing. Delayed-type hypersensitivity responses to common recall antigens of astronauts and cosmonauts have been shown to be decreased when tested during space flights. Additionally, natural killer cell and blastogenic activities are inhibited in samples taken from rats during space flight. Therefore, it is now clear that events occurring during space flight itself can affect immune responses. The biological significance of space flight-induced changes in immune parameters remains to be established; however, as duration of flights increases, the potential for difficulties due to impaired immune responses also increases.

Animals↗
PubMed2005

Effects of lung time constant, gas analyser delay and rise time on measurements of respiratory dead-space.

This study evaluated effects of mechanical time constants (tau(m)) of the respiratory system, delays between flow and CO(2) partial pressure (P(CO)(2)) signals and rise time of the CO(2) analyser on dead-space measurements. A computer model simulated low alveolar dead-space, high alveolar dead-space, 0.2 <or= tau(m) <or= 3.6 s and varying ventilation-perfusion ratios (V/Q). CO(2) expirograms were recorded from the model under each condition and from 22 anaesthetized intubated patients. P(CO)(2) signals were shifted with respect to flow to produce varying time delays and anatomic and physiological dead-spaces were calculated. The CO(2) analyser was simulated as a critically damped second-order system with 10-90% rise times of 25-400 ms. The error in measured dead-space increases approximately 2.5% per 10 ms signal delay for normal lungs (tau(m) = 1 s), but has low sensitivity (0.58% per 10 ms) to the rise time of the CO(2) analyser. Sensitivity of physiological dead-space, but not anatomic dead-space to delay is decreased in high alveolar dead-space and abnormal V/Q distribution. Shorter tau(m) increase the error sensitivity of both physiological and anatomic dead-spaces to both delay and rise time. P(CO)(2) and flow should be well synchronized, particularly when tau(m) are short, to avoid dead-space errors.

Aged↗
PubMed2002

A randomized clinical trial to compare three methods of orthodontic space closure.

AIM: To compare the rates of orthodontic space closure for: Active ligatures, polyurethane powerchain (Rocky Mountain Orthodontics, RMO Europe, Parc d'Innovation, Rue Geiler de Kaysersberg, 67400 Illkirch-Graffenstaden, Strasbourg, France) and nickel titanium springs. SAMPLE: Patients entering the space closure phase of fixed orthodontic treatment attending six orthodontic providers. Twelve patients received active ligatures (48 quadrants), 10 patients received powerchain (40 quadrants) and 11 patients, nickel-titanium springs (44 quadrants). METHOD: Patients were randomly allocated for treatment with active ligatures, powerchain or nickel titanium springs. Upper and lower study models were collected at the start of space closure (T(o)) and 4 months later (T(1)). We recorded whether the patient wore Class II or Class III elastics. Space present in all four quadrants was measured, by a calibrated examiner, using Vernier callipers at T(o) and T(1.) The rate of space closure, in millimetres per month (4 weeks) and a 4-monthly rate, was then calculated. Examiner reliability was assessed at least 2 weeks later. RESULTS: Mean rates of space closure were 0.35 mm/month for active ligatures, 0.58 mm/month for powerchain, and 0.81 mm/month for NiTi springs. No statistically significant differences were found between any methods with the exception of NiTi springs showing more rapid space closure than active ligatures (P < 0.05). There was no effect of inter-arch elastics on rate of space closure. CONCLUSIONS: NiTi springs gave the most rapid rate of space closure and may be considered the treatment of choice. However, powerchain provides a cheaper treatment option that is as effective. The use of inter-arch elastics does not appear to influence rate of space closure.

Adolescent↗
PubMed1996

The perirenal space: relationship of pathologic processes to normal retroperitoneal anatomy.

The perirenal space may be involved by disease processes that arise within or outside the perirenal space. Key anatomic details that dictate the features of perirenal processes include the renal capsule, the perirenal septa, the renal fascia, and the conic shape and inferomedial orientation of the perirenal space. Superiorly, the perirenal space is open to the bare area of the liver. The perirenal spaces communicate with one another at the level of the lower lumbar vertebrae. The hallmark of perirenal infection is localized or diffuse gas. Chronic urinoma appears as an encapsulated cystic mass, often aligned parallel with the perirenal space. Fat within an apparent spontaneous hematoma of the perirenal space suggests angiomyolipoma. Renal cell carcinoma, lymphoma, and melanoma are the most common causes of discrete solid masses in the perirenal space; metastases occur due to the characteristic lymphatic and vascular supply of the space. Amyloidosis and fibrosis create a nonspecific rind of soft tissue around the kidneys. Diaphragmatic pseudotumor produces a linear "lesion" in the perirenal space.

Amyloidosis↗
PubMed2004

Dynamic dead space in face masks used with noninvasive ventilators: a lung model study.

The aim of this study was to determine what the influence of different designs of face masks and different noninvasive ventilator modes would be upon total dynamic dead space. Using a spontaneous breathing model, total dynamic dead space was measured when using 19 commercially available face masks and a range of ventilators in various ventilation modes. Total dynamic dead space during spontaneous ventilation was increased above physiological dead space from 32% to 42% of tidal volume by using face masks. The use of noninvasive ventilation modes such as bilevel and continuous positive airway pressure, with continuous pressure throughout the expiratory phase, reduced total dynamic dead space to approach physiological dead space with most face masks. Pressure assist and pressure support ventilation decreased total dynamic dead space to a lesser degree, from 42% to 39% of tidal volume. Face masks with expiratory ports over the nasal bridge resulted in beneficial flow characteristics within the face mask and nasal cavity, so as to decrease total dynamic dead space to less than physiological dead space from 42% to 28.5% of tidal volume. Exhaust ports over the nasal bridge in face masks effect important decreases in dynamic dead space provided positive pressure throughout the expiratory phase is used.

Equipment Design↗
PubMed1993

The "subdural" space: a new look at an outdated concept.

This review considers the structure of the meninges, as seen at the electron microscopic level, with particular emphasis on the dura-arachnoid junction and whether a naturally occurring space is found at this interface. The classic view has been that a so-called subdural space is located between the arachnoid and dura and that subdural hematomas or hygromas are the result of blood or cerebrospinal fluid accumulating in this (preexisting) space. The dura is composed of elongated, flattened fibroblasts and copious amounts of extracellular collagen. A specialized layer of fibroblasts, the dural border cell layer, is found at the dura-arachnoid junction and is characterized by flattened fibroblasts, no extracellular collagen, extracellular spaces, and few cell junctions. These features combine to create a layer of the inner dura that is structurally weak when compared with external portions of the dura and the internally located arachnoid. The arachnoid layer is composed of larger cells with numerous cell junctions, no extracellular space, and no extracellular collagen. The occurrence of many tight junctions in this layer also serves as a barrier to the movement of fluids and ions. Fibroblasts specialized to form the arachnoid trabeculae attach to the inner surface of the arachnoid layer, bridge the subarachnoid space, and surround vessels in the subarachnoid space as well as attach to pia on the surface of the brain. Under normal conditions, there is no evidence of a naturally occurring space being extant at the dura-arachnoid junction. A space may appear at this point subsequent to pathological/traumatic processes that result in tissue damage with a cleaving opening of the structurally weakest plane in the meninges--through the dural border cell layer. Furthermore, when a space does appear, it is not "subdural" in location but rather within a morphologically distinct cell layer.

Animals↗
PubMed1996

Providing controlled environments for plant growth in space.

Providing a controlled environment for growth of plants in a space environment involves development of unique technologies for the various subsystems of the plant growing facility. These subsystems must be capable of providing the desired environmental control within the operational constraints of currently available space vehicles, primarily the US Space Shuttle or the Russian Space Station, MIR. These constraints include available electrical power, limited total payload mass, and limited volume of the payload. In addition, the space hardware must meet safety requirements for a man-rated space vehicle. The ASTROCULTURE (TM) space-based plant growth unit provides control of temperature, humidity, and carbon dioxide concentration of the plant chamber air. A light emitting diode (LED) unit provides red and blue photons with a total intensity adjustable from 0 to 500 micromoles m-2 s-1. Ethylene released by the plant material is removed with a non-consumable ethylene removable unit. A porous tube and rooting matrix subsystem is used to supply water and nutrients to the plants. The ASTROCULTURE(TM) flight unit is sized to be accommodated in a single middeck locker of the US Space Shuttle, the SPACEHAB module, and with slight modification in the SPACELAB module. The environmental control capabilities of the subsystems used in the ASTROCULTURE(TM) flight unit have been validated in a microgravity environment during five US Space Shuttle missions, including two with plants. The unique environmental control technologies developed for the space-based plant growth facility can be used to enhance the environmental control capabilities of terrestrial controlled environment plant chambers.

Agriculture↗
PubMed1999

STS-95 Space Experiments (plants and cell biology).

We report the outline of Space Experiments conducted on Space Shuttle (STS-95) launched in autumn of 1998. In this STS-95 mission, Japanese astronaut Dr. Chiaki Mukai achieved her 2nd space flight and conducted a part of 82 space experiments including Japanese experiments. US astronaut Senator John Glenn also achieved his second space flight, 36 years after his first space flight. Senator Glenn was a leader of the original (the first) 7 US astronauts and very famous in US because he succeeded US first orbital space flight around the earth. NASDA had started the project of space experiment using STS-95 at the summer of 1997, therefore we had only one year for the all preparation Yamashita, et al. Biological Sciences in Space, Vol.12 No.3(1998). Scientific results will be reported by investigators, therefore we report here how we had been developing the space experiment plan, on board operation procedure and ground operations including ground control experiments about four plant experiments and one cell biology experiment.

Biological Science Disciplines↗
PubMed2002

Pappus in optical space.

Optical space differs from physical space. The structure of optical space has generally been assumed to be metrical. In contradistinction, we do not assume any metric, but only incidence relations (i.e., we assume that optical points and lines exist and that two points define a unique line, and two lines a unique point). (The incidence relations have generally been assumed implicitly by earlier authors.) The condition that makes such an incidence structure into a projective space is the Pappus condition. The Pappus condition describes a projective relation between three collinear triples of points, whose validity can--in principle--be verified empirically. The Pappus condition is a necessary condition for optical space to be a homogeneous space (Lobatchevski hyperbolic or Riemann elliptic space) as assumed by, for example, the well-known Luneburg theory. We test the Pappus condition in a full-cue situation (open field, broad daylight, distances of up to 20 m, visual fields of up to 160 degrees diameter). We found that although optical space is definitely not veridical, even under full-cue conditions, violations of the Pappus condition are the exception. Apparently optical space is not totally different from a homogeneous space, although it is in no way close to Euclidean.

Adult↗
PubMed2002

[Ultrasound differentiation between benign enlargement of the subarachnoid space and brain atrophy].

Fluid collections surrounding the brain (pericerebral fluid collections) in infants can be caused by a variety of conditions: benign enlargement of the subarachnoid space, passive dilatation of the subarachnoid space due to brain atrophy, subdural hygroma and subdural effusion as a result of meningitis or subdural haematoma. An enlarged frontal subarachnoid space and normal or minimally enlarged ventricular size, with normal or increase head circumference is relatively common finding in infancy. Without associated brain anomalies, this finding predicts normal development of the child. In our study, we have followed up psychomotor development of 22 children, with increased diameters of subarachnoid spaces, detected by ultrasound examination of the brain, without associated brain anomalies. The inclusion criterion for study was enlarged subarachnoid space, measured at the conventional coronal section at the level of the interventricular foramen. The upper limits of each measurements were: 3 mm for sinocortical width, 4 mm for craniocortical width and 6 mm for the interhespheric width. The patients have been followed up to the age of 24 months. Each of them had normal development. 16 of them had normal head circumference. 6 of them had head circumference above the 97th percentile and their head circumference measurements have been plotted for the next 6 months after the diagnosis, to be certain that growth is paralleling the normal curve. It is important to differ benign enlargement of subarachnoid space from brain atrophy, which is quite "serious" diagnosis, with poor neurodevelopmental prognosis. The brain atrophy has been presented with passive dilatation of subarachnoid space and ventriculomegaly, as well. In the case of benign enlargement of subarachnoid space normal or minimally enlarged ventricular size is present. For proper interpretation of this ultrasound finding, correlation with head circumference is necessary. We recommend the head circumference percentile chart to be enclosed to the each brain sonography finding. The algorithm of the further neurological evaluation differs significantly in the case of benign enlargement of subarachnoid space and brain atrophy. In the case of benign enlargement of subarachnoid space further neuroimaging procedures are not needed (in our study it has been done for 6 patients). If the brain atrophy is suspected, further complete neurological examination is necessary.

Atrophy↗
PubMed1992

[Direct observation of the epidural space by the superfine fiberscope].

The anatomy of the epidural space was examined in 82 patients 3 to 90 years old who had indications of epidural anesthesia. The superfine fiberscope with an outer diameter of 0.8 mm was utilized for this study. It was advanced through 18 gauge Tuohy needle inserted into the epidural space. All findings were documented by videography. The epidural space was located at the thoracic intervertebral space (52 patients), at the lumbar interspace (27 patients) and at the caudal space (3 patients), using an 18-gauge Tuohy needle with either median or paramedian approach. The epidural space was identified by either hanging drop or loss of resistance method. 65 of 82 cases gave a clear view of epidural space. The epidural space presented as either a space that opened widely or a space that was occupied with large masses of fat. Vessels were encountered on the dura and the flaval ligaments, as well as in the connective tissue. Large amounts of connective tissue were present in all cases. No complications, such as accidental dural puncture, epidural hematoma, infection, nerve injury attributed to this technique were observed.

Adolescent↗
PubMed1998

Analysis of immune deviation elicited by antigens injected into the subretinal space.

PURPOSE: To determine whether the subretinal space supports the induction of deviant immune responses to cell-associated and soluble antigens and to elucidate factors influencing the immunologic properties of the subretinal space. METHODS: P815 mastocytoma cells were used as cell-associated antigens and were inoculated into the anterior chamber (AC), the vitreous cavity (VC), the subretinal space, and subconjunctivally in H2-compatible, but minor H-incompatible, BALB/c mice. Ovalbumin, as a soluble antigen, was similarly injected into eyes, after which recipient animals were immunized with ovalbumin and complete Freund's adjuvant. Delayed-type hypersensitivity (DTH) was assessed by ear challenge. To alter the conditions in the subretinal space, the outer blood-retinal barrier was disrupted by compromising retinal pigment epithelial (RPE) cells with a systemic injection of sodium iodate. Immune privilege in the AC was abolished by mild corneal cauterization. RESULTS: Antigen-specific DTH did not develop in mice in which alloantigenic tumor cells or ovalbumin was injected into the AC, the VC, or the subretinal space, and the mice's spleens contained lymphocytes capable of suppressing DTH when adoptively transferred into naive mice. When RPE cells were compromised with sodium iodate, tumor cells or ovalbumin injected into the subretinal space or the VC did not induce immune deviation, although the AC of these eyes still promoted AC-associated immune deviation. By contrast, when immune privilege in the AC was abolished by corneal cauterization, neither tumor cells nor ovalbumin injected into the subretinal space or the VC of eyes elicited immune deviation. CONCLUSIONS: The subretinal space supports immune deviation for histoincompatible tumor cells and soluble protein antigens by actively suppressing antigen-specific DTH. Acute loss of immune privilege in the subretinal space and the VC does not cause loss of privilege in the AC, but abolition of immune privilege in the AC eliminates the capacity of the subretinal space and the VC to support immune deviation to antigens injected locally.

Adoptive Transfer↗
PubMed1996

Examination of joint space by magnetic resonance imaging in anatomically normal knees.

The medical and lateral knee joint spaces of 184 patients who had anatomically normal knees were measured by using magnetic resonance imaging (MRI) method. The findings were compared according to age, sex, height, and body mass index changes of the individuals and the mean values of medial and lateral knee joint spaces were calculated in every group. The results show that in an anatomically normal population, all the individuals have larger lateral knee joint spaces than medial knee joint spaces. The patients lose knee joint space regularly with increasing age. Children have larger knee joint spaces than adults. Men have larger knee joint spaces than women. The knee joint space size of the patients increase regularly with increasing height up to 180 cm. The patients, who are taller than 180 cm do not show any marked difference in joint space size, when compared with the patients whose heights differ in between 171-180 cm. Knee joint space size is not related to the body mass index of the individual.

Adolescent↗
PubMed1998

Single-shot half k-space high-resolution gradient-recalled EPI for fMRI at 3 Tesla.

Half k-space gradient-recalled echo-planar imaging (GR-EPI) is discussed in detail. T2* decay during full k-space GR-EPI gives rise to unequal weighting of the lines of k-space, loss of signal intensity at the center of k-space, and a point-spread function that limits resolution. In addition, the long readout time for high-resolution full k-space acquisition gives rise to severe susceptibility effects. These problems are substantially reduced by acquiring only half of k-space and filling the empty side by Hermitian conjugate formation. Details of the pulse sequence and image reconstruction are presented. The point-spread function is 3(1/2) times narrower for half than full k-space acquisition. Experiments as well as theoretical considerations were carried out in a context of fMRI using a whole-brain local gradient and an RF coil at 3 Tesla. Using a bandwidth of +/-83 kHz, well-resolved single-shot images of the human brain, as well as good quality fMRI data sets were obtained with a matrix of 192 x 192 over 16 x 16 cm2 FOV using half k-space techniques. The combination of high spatial resolution using the methods presented in this article and the high temporal resolution of EPI opens opportunities for research into fMRI contrast mechanisms. Increase of percent signal change as the resolution increases is attributed to reduction of partial volume effects of activated voxels. Histograms of fMRI pixel responses are progressively weighted to higher percent signal changes as the resolution increases. The conclusion has been reached that half k-space GR-EPI is generally superior to full k-space GR-EPI and should be used even for low-resolution (64 x 64) EPI.

Brain↗
PubMed2006

Three-dimensional volume rendering of tibiofibular joint space and quantitative analysis of change in volume due to tibiofibular syndesmosis diastases.

OBJECTIVE: The diagnosis of ankle syndesmosis injuries is made by various imaging techniques. The present study was undertaken to examine whether the three-dimensional reconstruction of axial CT images and calculation of the volume of tibiofibular joint space enhances the sensitivity of diastases diagnoses or not. DESIGN: Six adult cadaveric ankle specimens were used for spiral CT-scan assessment of tibiofibular syndesmosis. After the specimens were dissected, external fixation was performed and diastases of 1, 2, and 3 mm was simulated by a precalibrated device. Helical CT scans were obtained with 1.0-mm slice thickness. The data was transferred to the computer software AcquariusNET. Then the contours of the tibiofibular syndesmosis joint space were outlined on each axial CT slice and the collection of these slices were stacked using the computer software AutoCAD 2005, according to the spatial arrangement and geometrical coordinates between each slice, to produce a three-dimensional reconstruction of the joint space. The area of each slice and the volume of the entire tibiofibular joint space were calculated. The tibiofibular joint space at the 10th-mm slice level was also measured on axial CT scan images at normal, 1, 2 and 3-mm joint space diastases. RESULTS: The three-dimensional volume-rendering of the tibiofibular syndesmosis joint space from the spiral CT data demonstrated the shape of the joint space and has been found to be a sensitive method for calculating joint space volume. We found that, from normal to 1 mm, a 1-mm diastasis increases approximately 43% of the joint space volume, while from 1 to 3 mm, there is about a 20% increase for each 1-mm increase. CONCLUSIONS: Volume calculation using this method can be performed in cases of syndesmotic instability after ankle injuries and for preoperative and postoperative evaluation of the integrity of the tibiofibular syndesmosis.

Adult↗
PubMed1984

Water movement from intracristal spaces in isolated liver mitochondria.

When analyzing mitochondria isolated in a sucrose medium that had been embedded for thin sectioning according to one low denaturation embedding technique, large intracristal spaces were present in close to 90% of the mitochondria. The two crista membranes were closely apposed in only 40% of all cristae. When the mitochondria were transferred to an incubation medium, the percentage of mitochondria with intracristal spaces was reduced to 40%. About 90% of all cristae were lacking any space separating the two crista membranes. The presence of inorganic phosphate in the medium was required for the closing of the intracristal spaces. The percentage of cristae lacking an intracristal space remained the same after addition of substrate for respiration (state 4) and of ADP (state 3). Inhibition or uncoupling of respiration led to an increase in the percentage of intracristal spaces, showing that oxidative phosphorylation is required to maintain the crista membranes closely apposed. The appearance and disappearance of the intracristal spaces was an indication of water movements across the crista membranes. The mean volume of the mitochondria increased 33% when they were transferred from the sucrose medium to the incubation medium, showing that the removal of water from the cristae was not caused by a passive osmotic effect. Addition of substrate made the volume decrease by 28%. After further addition of ADP, the volume decreased another 23%. No change in volume was associated with inhibition or uncoupling of respiration. The observations revealed that water can move into or out of the cristae independently of water movement out from the entire mitochondrion. Therefore, the water moving out from or into the cristae is translocated across the cristae membrane. The observations are interpreted to reveal the presence of a mechanism that actively prevents water from accumulating in the crista membrane. This mechanism allows for a low water activity to be maintained within the membrane. The variations in the frequency of intracristal spaces occurred without any simultaneous changes in the width of the space appearing between the two surface membranes after isolation of the mitochondria. The observations, therefore, do not agree with the concept that there is an outer compartment that communicates freely with intracristal spaces.

2,4-Dinitrophenol↗
PubMed1997

Fillers and spaces in text: the importance of word recognition during reading.

Current theories of reading eye movements claim that reading saccades are programmed primarily on the basis of information about the length of the upcoming word, determined by low-level visual processes that detect spaces to the right of fixation. Many studies attempted to test this claim by filling spaces between words with various non-space symbols (fillers). This manipulation, however, confounds the effect of inserting extraneous characters into text with the effect of obscuring word boundaries by filling spaces. We performed the control conditions necessary to unconfound these effects. Skilled readers read continuous stories aloud and silently. Three factors were varied: (i) position of the fillers in the text (at the beginning, the end, or surrounding each word); (ii) the presence or absence of spaces in the text; and (iii) the effect of the type of filler on word recognition (from greatest effect to least effect: Latin letters, Greek letters, digits and shaded boxes). The effect of fillers on reading depended more on the type of filler than on the presence of spaces. The greater effect the fillers had on word recognition, the more they showed reading. Surrounding each word with digits or Greek letters slowed reading as much as filling spaces with these symbols. Surrounding each word with randomly chosen letters, while preserving spaces, slowed reading by 44-75%--as much as, or more than, removing spaces from normal text. Removing spaces from text with Latin-letter fillers slowed reading by only 10-20% more. We conclude that fillers in text disrupt reading by affecting word recognition directly, without necessarily affecting the eye movement pattern.

Humans↗