Even though retinal images of objects change their locations following each eye movement, we perceive a stable and continuous world. One possible mechanism by which the brain achieves such visual stability is to construct a craniotopic coordinate by integrating retinal and extraretinal information. There have been several proposals on how this may be done, including eye-position modulation (gain fields) of retinotopic receptive fields (RFs) and craniotopic RFs. In the present study, we investigated coordinate systems used by RFs in the lateral intraparietal (LIP) cortex and frontal eye fields (FEF) and compared the two areas. We mapped the two-dimensional RFs of neurons in detail under two eye fixations and analyzed how the RF of a given neuron changes with eye position to determine its coordinate representation. The same recording and analysis procedures were applied to the two brain areas. We found that, in both areas, RFs were distributed from retinotopic to craniotopic representations. There was no significant difference between the distributions in the LIP and FEF. Only a small fraction of neurons was fully craniotopic, whereas most neurons were between the retinotopic and craniotopic representations. The distributions were strongly biased toward the retinotopic side but with significant craniotopic shifts. These results suggest that there is only weak evidence for craniotopic RFs in the LIP and FEF, and that transformation from retinotopic to craniotopic coordinates in these areas must rely on other factors such as gain fields.
Animals ; Macaca ; Visual Fields ; Frontal Lobe/physiology* ; Eye Movements ; Brain

Biomechanical Phenomena ; Eye Movements ; Neurons/physiology* ; Pursuit, Smooth ; Saccades

OBJECTIVES: To explore the difference of eye movement characteristics between uncooperative and cooperative subjects with mental disorder after cerebral trauma. METHODS: Thirty-nine subjects which needed psychiatric impairment assessment were selected. According to the binomial forced-choice digit memory test （BFDMT）, all subjects were divided into cooperative and uncooperative groups. The subjects were asked to take the image completion test from Wechsler adult intelligence scale. Meanwhile, the data of eye movement track, fixation, saccade, pupil and blink were recorded by the track system of eye movement. RESULTS: There were significantly differences （P<0.05） in the data of saccade between cooperative （10 cases） and uncooperative groups （29 cases）. The frequency, time, amplitude, acceleration of saccadic in uncooperative group were significantly higher than cooperation group. The saccade latencies of cooperation group increased more than uncooperative group. There was a significant difference （P<0.05） in total discrete distance, average distance and total time of fixation between two groups, while the average duration time, number and frequency of fixation had no significantly difference （P>0.05） between two groups. And the blink frequency of cooperation group was higher than uncooperative group. CONCLUSIONS Eye movement can be an objective index for the primary judgment of cooperation level.
Adult ; Eye Movement Measurements ; Eye Movements/physiology* ; Humans ; Intelligence Tests ; Saccades/physiology* ; Wechsler Scales

PURPOSE: To evaluate the efficacy and safety of customized orbital decompression surgery combined with eyelid surgery or strabismus surgery for mild to moderate thyroid-associated ophthalmopathy (TAO). METHODS: Twenty-seven consecutive subjects who were treated surgically for proptosis with disfigurement or diplopia after medical therapy from September 2009 to July 2012 were included in the analysis. Customized orbital decompression surgery with correction of eyelid retraction and extraocular movement disorders was simultaneously performed. The patients had a minimum preoperative period of 3 months of stable range of ocular motility and eyelid position. All patients had inactive TAO and were euthyroid at the time of operation. Preoperative and postoperative examinations, including vision, margin reflex distance, Hertel exophthalmometry, ocular motility, visual fields, Goldmann perimetry, and subject assessment of the procedure, were performed in all patients. Data were analyzed using paired t-test (PASW Statistics ver. 18.0). RESULTS: Forty-nine decompressions were performed on 27 subjects (16 females, 11 males; mean age, 36.6 +/- 11.6 years). Twenty-two patients underwent bilateral operations; five required only unilateral orbital decompression. An average proptosis of 15.6 +/- 2.2 mm (p = 0.00) was achieved, with a mean preoperative Hertel measurement of 17.6 +/- 2.2 mm. Ocular motility was corrected through recession of the extraocular muscle in three cases, and no new-onset diplopia or aggravated diplopia was noted. The binocular single vision field increased in all patients. Eyelid retraction correction surgery was simultaneously performed in the same surgical session in 10 of 49 cases, and strabismus and eyelid retraction surgery were performed in the same surgical session in two cases. Margin reflex distance decreased from a preoperative average of 4.3 +/- 0.8 to 3.8 +/- 0.5 mm postoperatively. CONCLUSIONS: The customized orbital decompression procedure decreased proptosis and improved diplopia, in a range comparable to those achieved through more stepwise techniques, and had favorable cosmetic results when combined with eyelid surgery or strabismus surgery for mild to moderate TAO.
Adolescent ; Adult ; Decompression, Surgical/*methods ; Exophthalmos/*surgery ; Eye Movements/physiology ; Eyelids/*surgery ; Female ; Graves Ophthalmopathy/*surgery ; Humans ; Male ; Middle Aged ; Oculomotor Muscles/surgery ; *Ophthalmologic Surgical Procedures ; Orbit/*surgery ; Retrospective Studies ; Strabismus/*surgery ; Visual Field Tests ; Visual Fields/physiology

PURPOSE: To evaluate differences in self-identity in patients diagnosed with strabismus, patients who underwent strabismus surgery, and healthy control individuals. METHODS: Self-identity testing was done during a military service physical examination. There were three subject groups: subjects with strabismus (group 1), subjects who had undergone corrective strabismus surgery (group 2), and subjects free of strabismus (group 3). The self-identity test was comprised of six sub-sections (subjectivity, self-acceptance, future confidence, goal orientation, initiative, and familiarity). Statistical significance of the sub-sections was compared across the three groups. Correlations in age at the time of surgery and across the six sub-sections were investigated in group 2. RESULTS: A total of 351 subjects were enrolled in the study; 96 subjects were in group 1, 108 subjects were in group 2, and 147 subjects were in group 3. Significant differences were evident in subjectivity, self-acceptance, initiative and familiarity between groups 1 and 3. No significant differences were found between groups 2 and 3. In group 2, statistical significance was evident between age at surgery and initiative and familiarity (r = −0.333, p < 0.001; r = −0.433, p < 0.001, respectively). CONCLUSIONS: Self-identity is greater in non-strabismus subjects than strabismus subjects. Correction of strabismus may increase self-identity levels.
Adolescent ; Adult ; Eye Movements/*physiology ; *Facial Expression ; Female ; Humans ; Male ; Oculomotor Muscles/*physiopathology/surgery ; Ophthalmologic Surgical Procedures ; Retrospective Studies ; *Self Concept ; Strabismus/physiopathology/*psychology/surgery

No abstract available.
Child ; Eye Movements/*physiology ; Humans ; Male ; Oculomotor Muscles/physiopathology/*surgery ; Ophthalmologic Surgical Procedures/*methods ; Strabismus/physiopathology/*surgery ; Syndrome

PURPOSE: The purpose of this study is to compare the magnitude and axis of astigmatism induced by a combined inferior oblique (IO) anterior transposition procedure with lateral rectus (LR) recession versus LR recession alone. METHODS: Forty-six patients were retrospectively analyzed. The subjects were divided into two groups: those having concurrent inferior oblique muscle overaction (IOOA) and intermittent exotropia (group 1, 20 patients) and those having only intermittent exotropia as a control (group 2, 26 patients). Group 1 underwent combined anterior transposition of IO with LR recession and group 2 underwent LR recession alone. Induced astigmatism was defined as the difference between preoperative and postoperative astigmatism using double-angle vector analysis. Cylinder power, axis of induced astigmatism, and spherical equivalent were analyzed at 1 week, 1 month, and 3 months after surgery. RESULTS: Larger changes in the axis of induced astigmatism were observed in group 1, with 4.5° incyclotorsion, than in group 2 at 1 week after surgery (axis, 84.5° vs. 91°; p < 0.001). However, there was no statistically significant inter-group difference thereafter. Relaxation and rapid regression in the incyclotorsion of induced astigmatism were observed over-time. Spherical equivalent significantly decreased postoperatively at 1 month in both groups, indicating a myopic shift (p = 0.011 for group 1 and p = 0.019 for group 2) but did not show significant differences at 3 months after surgery (p = 0.107 for group 1 and p = 0.760 for group 2). CONCLUSIONS: Combined IO anterior transposition procedures caused an increased change in the axis of induced astigmatism, including temporary incyclotorsion, during the first week after surgery. However, this significant difference was not maintained thereafter. Thus, combined IO surgery with LR recession does not seem to produce a sustained astigmatic change, which can be a potential risk factor of postoperative amblyopia or diplopia compared with LR recession alone.
Astigmatism/diagnosis/*etiology/physiopathology ; Child ; Exotropia/diagnosis/physiopathology/*surgery ; Eye Movements/*physiology ; Female ; Follow-Up Studies ; Humans ; Male ; Oculomotor Muscles/*surgery ; Ophthalmologic Surgical Procedures/*methods ; Retrospective Studies ; Treatment Outcome ; Vision, Binocular/*physiology

BACKGROUNDDevelopmental dyslexia (DD) is a disorder in which children with normal intelligence and sensory abilities show learning deficits in reading. Abnormal eye movements have been found in DD. However, eye-movement abnormalities during visual search among Chinese children with DD remain unknown. We aimed to identify the eyemovement characteristics and search efficiency of Chinese children with DD during visual search for targets of different conceptual categories, under same-category conditions.

METHODSWe compared 32 Chinese dyslexic children and 39 non-dyslexic children in visual search tasks, which were assessed using EyeLink II High-Speed Eye Tracker (SR Research Ltd., Canada). Letters, single Chinese characters, digits, Chinese phrases, figures and facial expressions were used as stimuli. Targets were similar to distractors in meaning, phonology and/or shape.

RESULTSA main effect of task on visual search scores and all eye-movement parameters were found. Search scores, average saccade amplitude and saccade distance were significantly smaller in the DD group than in the controls. An interaction between group and task was found for pupil diameter.

CONCLUSIONSUnlike normal readers, children with DD had a reduction in the visual attention span and search accuracy. Besides, children with DD could not increase their mental workload with increase in task difficulty. The conceptual category of the stimulus materials significantly impacts search speed, accuracy and eye-movement parameters.

Adolescent ; Asian Continental Ancestry Group ; Child ; Dyslexia ; physiopathology ; Eye Movements ; physiology ; Female ; Humans ; Male

Sleep is a highly organized and complicated state that is fundamental to life. We have an absolute need to sleep during about one-third of our lives. There are two types of sleep, non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. NREM sleep is divided into stages 1, 2, and 3 which is representing a degree of relative depth in sleep. Each sleep stage shows unique features including some variations in electroencephalographic waves, eye movements, and muscle tone. Although sleep pattern changes are associated with aging, how sleep physiology and sleep patterns change over an individual's life span is not well-defined. Circadian rhythms, which are the daily rhythms in physiology and behavior, regulate the sleep-wake cycle. Comprehensive understanding of normal sleep physiology should be very important to better understand not only the effects of sleep related diseases but also the impacts of pathological sleep on various diseases of other systemic organs. This review aims to enhance knowledge focused on normal sleep physiology and its regulation.
Aging ; Circadian Rhythm ; Eye Movements ; Muscles ; Neurobiology ; Physiology* ; Sleep Stages ; Sleep, REM

PURPOSE: To evaluate factors associated with the direction of horizontal deviation in the sensory strabismus of patients with unilateral organic amblyopia. METHODS: The medical charts of 53 patients who had been diagnosed with sensory strabismus between 2000 and 2009 were reviewed retrospectively. The underlying ocular disease, time of onset and the duration of vision impairment, refractive error and axial length of the fixing eye, and the direction and angle of deviation were analyzed to determine the distribution of underlying diseases and any factors relevant to determining the direction of the horizontal deviation. RESULTS: Congenital cataracts were the most common underlying disease, found in 33 patients, followed by acquired cataracts, optic nerve disorders, retinal detachment, glaucoma and lens subluxation. Among the 50 patients with horizontal strabismus, 11 had esotropia and 39 had exotropia. The incidence of esotropia was significantly higher when the fixing eye had hyperopia or emmetropia, than when the eye was myopic. Age of onset of vision deterioration and at diagnosis of sensory strabismus, and the axial length of the fixing eye had no relationship to the direction of horizontal deviation. In addition, the duration of visual impairment had no significant relationship with the direction or extent of horizontal deviation. CONCLUSIONS: The most common cause of sensory strabismus was congenital cataracts and the most frequent type of strabismus was exotropia. With respect to the direction of horizontal strabismus, esotropia occurred significantly more often when the refractive error of the fixing eye was hyperopia or emmetropia than when the fixing eye was myopic.
Adolescent ; Adult ; Amblyopia/*complications/physiopathology ; Cataract/complications/congenital/physiopathology ; Child ; Child, Preschool ; Eye Movements/*physiology ; Female ; Follow-Up Studies ; Humans ; Infant ; Infant, Newborn ; Male ; Oculomotor Muscles/*physiopathology ; Refractive Errors ; Retrospective Studies ; Risk Factors ; Strabismus/etiology/*physiopathology ; Visual Acuity ; Young Adult