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Paradoxical sleep characteristics and cultural environment. Preliminary results

Petre-Quadens O, Hussain H, Balaratnan C

Acta Neurol Belg, 1975 Mar;75(2):85-92.
PMID: 168717

The Temiars are a tribe of negroid pygmies of basically Proto-Malaysian affinities. Field-work in the Malaysian jungle provided some observations on the sleep-wakefulness cycle of two young Temiar adults. This cycle was monophasic circumstances permitting. Their rest-activity cycle at night was similar in the jungle and in the laboratory. Polygraphic total night-sleep recordings were made with both of them in the EEG laboratory in the Hospital Besar in Kuala Lumpur. The eye-movement frequencies of PS were compared with those from young adults of the West. Although the differences were not statistically significant, the Rem-densities of the Temiars were constantly at the low side. The significance of the results are being discussed.

Matched MeSH terms: Eye Movements
Time course of inhibition of return in a spatial cueing paradigm with distractors

Eng V, Lim A, Janssen SMJ, Satel J

Acta Psychol (Amst), 2018 Feb;183:51-57.
PMID: 29328938 DOI: 10.1016/j.actpsy.2017.12.011

Studies of endogenous and exogenous attentional orienting in spatial cueing paradigms have been used to investigate inhibition of return, a behavioral phenomenon characterized by delayed reaction time in response to recently attended locations. When eye movements are suppressed, attention is covertly oriented to central or peripheral stimuli. Overt orienting, on the other hand, requires explicit eye movements to the stimuli. The present study examined the time course of slowed reaction times to previously attended locations when distractors are introduced into overt and covert orienting tasks. In a series of experiments, manual responses were required to targets following central and peripheral cues at three different cue-target intervals, with and without activated oculomotor systems. The results demonstrate that, when eye movements are suppressed, behavioral inhibition is reduced or delayed in magnitude by the presence of a distractor relative to conditions without distractors. However, the time course of behavioral inhibition when eye movements are required remains similar with or without distractors.

Matched MeSH terms: Eye Movements/physiology
Fulltext A simple model to demonstrate the movements and the axes of the eyeball

Nayak S, Soumya KV

Adv Physiol Educ, 2009 Dec;33(4):356-7.
PMID: 19948688 DOI: 10.1152/advan.00047.2009
Matched MeSH terms: Eye Movements/physiology*
Stimulus-response incompatibility eliminates inhibitory cueing effects with saccadic but not manual responses

Eng V, Lim A, Kwon S, Gan SR, Jamaluddin SA, Janssen SMJ, et al.

Atten Percept Psychophys, 2017 May;79(4):1097-1106.
PMID: 28229429 DOI: 10.3758/s13414-017-1295-8

There are thought to be two forms of inhibition of return (IOR) depending on whether the oculomotor system is activated or suppressed. When saccades are allowed, output-based IOR is generated, whereas input-based IOR arises when saccades are prohibited. In a series of 4 experiments, we mixed or blocked compatible and incompatible trials with saccadic or manual responses to investigate whether cueing effects would follow the same pattern as those observed with more traditional peripheral onsets and central arrows. In all experiments, an uninformative cue was displayed, followed by a cue-back stimulus that was either red or green, indicating whether a compatible or incompatible response was required. The results showed that IOR was indeed observed for compatible responses in all tasks, whereas IOR was eliminated for incompatible trials-but only with saccadic responses. These findings indicate that the dissociation between input- and output-based forms of IOR depends on more than just oculomotor activation, providing further support for the existence of an inhibitory cueing effect that is distinct to the manual response modality.

Matched MeSH terms: Eye Movements/physiology
The effectiveness of sub-Tenon's infiltration of local anaesthesia for cataract surgery

Verghese I, Sivaraj R, Lai YK

Aust N Z J Ophthalmol, 1996 May;24(2):117-20.
PMID: 9199741

PURPOSE: To determine if adequate anesthesia and akinesia could be obtained using an inferonasal quadrant sub-Tenons anaesthesia for cataract surgery.
METHODS: The sub-Tenons method of local anaesthesia was used in 50 patients undergoing extracapsular cataract extraction and lens implantation. The technique following was that described by JD Stevens in his study of 50 patients. Posterior sub-Tenons space was approached through a conjunctival incision in the inferonasal quadrant and the anaesthetic solution delivered by an irrigating cannula. The patients were assessed for residual ocular movements just before surgery. Effectiveness of anaesthesia was assessed during surgery using a verbal pain rating score. Scoring was based on the concept of a visual analogue pain score chart.
RESULTS: Total akinesia was obtained in 20% patients and total anaesthesia in 24% patients. The remainder of the patients had adequate akinesia and anaesthesia to proceed with and complete the surgery.
CONCLUSION: This method provides satisfactory anaesthesia for cataract surgery.

Matched MeSH terms: Eye Movements/drug effects
Fulltext Cerebral venous thrombosis: an unusual cause of complex ophthalmoplegia in an elderly man

Ng, Benjamin Han Sim, Prakash Supahiah, Goh, Siew Yuen

Borneo Journal of Medical Sciences, 2021;15(1):45-48.
MyJurnal

Cerebral venous thrombosis (CVT) is a neurological condition occurring because of thrombosis involving the cerebral venous sinuses. This case report is an unusual clinical manifestation of cerebral venous thrombosis in a 76-year-old Chinese man who presented with restricted eye movement and double vision. Despite extensive investigation, there was no better explanation for his clinical symptom and sign apart from cerebral venous thrombosis which was confirmed by magnetic resonance venography (MRV) of the brain. Once cerebral venous thrombosis was diagnosed, he was initiated on anticoagulation and discharged with oral warfarin. This case emphasizes the need to consider cerebral venous thrombosis as one of the rare causes of complex ophthalmoplegia especially when typical cardiovascular risk factors are lacking in an individual.

Matched MeSH terms: Eye Movements
The impact of cognitive load on reward evaluation

Krigolson OE, Hassall CD, Satel J, Klein RM

Brain Res, 2015 Nov 19;1627:225-32.
PMID: 26431993 DOI: 10.1016/j.brainres.2015.09.028

The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial-frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with previous work, we found that the higher level of cognitive load reduced the amplitude of the feedback-related negativity, a component of the human event-related brain potential associated with reward evaluation within the medial-frontal cortex. Importantly, our results provide further support that increased cognitive load reduces the functional efficacy of a neural system associated with reward processing.

Matched MeSH terms: Eye Movements
Ocular myasthenia gravis and idiopathic orbital inflammatory disease: double the trouble!

Sharudin SN, Govindasamy G, Mohamad NF, Kanesalingam R, Vasudevan SK

Can J Ophthalmol, 2018 04;53(2):e55-e58.
PMID: 29631841 DOI: 10.1016/j.jcjo.2017.07.024
Matched MeSH terms: Eye Movements/physiology*
Seeing the world through others' minds: Inferring social context from behaviour

Teoh Y, Wallis E, Stephen ID, Mitchell P

Cognition, 2017 02;159:48-60.
PMID: 27886521 DOI: 10.1016/j.cognition.2016.11.003

Past research tells us that individuals can infer information about a target's emotional state and intentions from their facial expressions (Frith & Frith, 2012), a process known as mentalising. This extends to inferring the events that caused the facial reaction (e.g. Pillai, Sheppard, & Mitchell, 2012; Pillai et al., 2014), an ability known as retrodictive mindreading. Here, we enter new territory by investigating whether or not people (perceivers) can guess a target's social context by observing their response to stimuli. In Experiment 1, perceivers viewed targets' responses and were able to determine whether these targets were alone or observed by another person. In Experiment 2, another group of perceivers, without any knowledge of the social context or what the targets were watching, judged whether targets were hiding or exaggerating their facial expressions; and their judgments discriminated between conditions in which targets were observed and alone. Experiment 3 established that another group of perceivers' judgments of social context were associated with estimations of target expressivity to some degree. In Experiments 1 and 2, the eye movements of perceivers also varied between conditions in which targets were observed and alone. Perceivers were thus able to infer a target's social context from their visible response. The results demonstrate an ability to use other minds as a window onto a social context that could not be seen directly.

Matched MeSH terms: Eye Movements
The prioritization of visuo-spatial associations during mental imagery

Umar H, Mast FW, Cacchione T, Martarelli CS

Cogn Process, 2021 May;22(2):227-237.
PMID: 33404898 DOI: 10.1007/s10339-020-01010-5

While previous research has shown that during mental imagery participants look back to areas visited during encoding it is unclear what happens when information presented during encoding is incongruent. To investigate this research question, we presented 30 participants with incongruent audio-visual associations (e.g. the image of a car paired with the sound of a cat) and later asked them to create a congruent mental representation based on the auditory cue (e.g. to create a mental representation of a cat while hearing the sound of a cat). The results revealed that participants spent more time in the areas where they previously saw the object and that incongruent audio-visual information during encoding did not appear to interfere with the generation and maintenance of mental images. This finding suggests that eye movements can be flexibly employed during mental imagery depending on the demands of the task.

Matched MeSH terms: Eye Movements
Looking at remembering: Eye movements, pupil size, and autobiographical memory

Janssen SMJ, Foo A, Johnson SN, Lim A, Satel J

Conscious Cogn, 2021 03;89:103089.
PMID: 33607423 DOI: 10.1016/j.concog.2021.103089

To examine the relationship between visual imagery and autobiographical memory, eye position and pupil size were recorded while participants first searched for memories and then reconstructed the retrieved memories (Experiment 1), or only searched for memories (Experiment 2). In Experiment 1, we observed that, although recollective experience was not associated with the number of fixations per minute, memories that took longer to retrieve were linked to increased pupil size. In Experiment 2, we observed that directly retrieved memories were recalled more quickly and were accompanied by smaller pupils than generatively retrieved memories. After correcting for response time, retrieval mode also produced an effect, showing that decreased pupil size is not simply due to directly retrieved memories being recalled more quickly. These findings provide compelling evidence that objective measures, such as pupil size, can be used alongside subjective measures, such as self-reports, to distinguish between directly retrieved and generatively retrieved memories.

Matched MeSH terms: Eye Movements
Fulltext Relationship between autonomic arousal and attention orienting in children and adolescents with ADHD, autism and co-occurring ADHD and autism

Bellato A, Arora I, Kochhar P, Ropar D, Hollis C, Groom MJ

Cortex, 2023 Sep;166:306-321.
PMID: 37459680 DOI: 10.1016/j.cortex.2023.06.002

INTRODUCTION: Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) may be characterized by different profiles of visual attention orienting. However, there are also many inconsistent findings emerging from the literature, probably due to the fact that the potential effect of autonomic arousal (which has been proposed to be dysregulated in these conditions) on oculomotor performance has not been investigated before. Moreover, it is not known how visual attention orienting is affected by the co-occurrence of ADHD and autism in people with a double diagnosis.
METHODS: 99 children/adolescents with or without ADHD and/or autism (age 10.79 ± 2.05 years, 65% boys) completed an adapted version of the gap-overlap task (with baseline and overlap trials only). The social salience and modality of stimuli were manipulated between trials. Eye movements and pupil size were recorded. We compared saccadic reaction times (SRTs) between diagnostic groups and investigated if a trial-by-trial association existed between pre-saccadic pupil size and SRTs.
RESULTS: Faster orienting (shorter SRT) was found for baseline compared to overlap trials, faces compared to non-face stimuli and-more evidently in children without ADHD and/or autism-for multi-modal compared to uni-modal stimuli. We also found a linear negative association between pre-saccadic pupil size and SRTs, in autistic participants (without ADHD), and a quadratic association in children with ADHD (without autism), for which SRTs were slower when intra-individual pre-saccadic pupil size was smallest or largest.
CONCLUSION: Our findings are in line with previous literature and indicate a possible effect of dysregulated autonomic arousal on oculomotor mechanisms in autism and ADHD, which should be further investigated in future research studies with larger samples, to reliably investigate possible differences between children with single and dual diagnoses.

Matched MeSH terms: Eye Movements
The Influence of Stimulus Repetition Rate on Tone-Evoked Post-Auricular Muscle Response (PAMR) Threshold

Zakaria MN, Abdullah R, Nik Othman NA

Ear Hear, 2018 11 22;40(4):1039-1042.
PMID: 30461445 DOI: 10.1097/AUD.0000000000000676

OBJECTIVES: Post-auricular muscle response (PAMR) is a large myogenic potential that can be useful in estimating behavioral hearing thresholds when the recording protocol is optimal. The main aim of the present study was to determine the influence of stimulus repetition rate on PAMR threshold.
DESIGN: In this repeated-measures study, 20 normally hearing adults aged between 18 and 30 years were recruited. Tone bursts (500, 1000, 2000, and 4000 Hz) were used to record PAMR thresholds at 3 different stimulus repetition rates (6.1/s, 11.1/s, and 17.1/s).
RESULTS: Statistically higher PAMR thresholds were found for the faster stimulus rate (17.1/s) compared with the slower stimulus rate (6.1/s) (p < 0.05). For all stimulus rates and frequencies, significant correlations were found between PAMR and pure-tone audiometry thresholds (r = 0.62 to 0.82).
CONCLUSIONS: Even though the stimulus rate effect was significant at most of the tested frequencies, the differences in PAMR thresholds between the rates were small (<5 dB). Nevertheless, based on the correlation results, we suggest the use of 11.1/s stimulus rate when recording PAMR thresholds.

Matched MeSH terms: Eye Movements
Fulltext Case report: progression of pre-septal cellulitis to orbital subperiosteal abscess despite intravenous broad-spectrum antibiotics in a child

Noor Aniah A, Norshamsiah MD, Safinaz MK, Bastion, MLC, Mawaddah A

Journal of Surgical Academia, 2016;6(1):62-65.
MyJurnal

We report a case of a 7-year-old girl who initially presented with painless right eyelid swelling with full extra-ocular movement (EOM). She was treated with intravenous broad-spectrum antibiotics for preseptal cellulitis but her condition worsened. An urgent magnetic resonance imaging (MRI) of the brain and orbit showed orbital abscess, subperiosteal abscess in the medial orbital wall and evidence of sinusitis in the anterior ethmoidal air cells. She underwent Endoscopic Orbital Decompression (EOD) surgery on day 4 of presentation and her condition improved remarkably. We report a case of orbital abscess with subperiosteal abscess in the medial orbital wall. This case highlights the possibility of progression of orbital cellulitis despite administration of a broad-spectrum antibiotic.

Matched MeSH terms: Eye Movements
Using other minds as a window onto the world: guessing what happened from clues in behaviour

Pillai D, Sheppard E, Ropar D, Marsh L, Pearson A, Mitchell P

J Autism Dev Disord, 2014 Oct;44(10):2430-9.
PMID: 24710812 DOI: 10.1007/s10803-014-2106-x

It has been proposed that mentalising involves retrodicting as well as predicting behaviour, by inferring previous mental states of a target. This study investigated whether retrodiction is impaired in individuals with autism spectrum disorders (ASD). Participants watched videos of real people reacting to the researcher behaving in one of four possible ways. Their task was to decide which of these four "scenarios" each person responded to. Participants' eye movements were recorded. Participants with ASD were poorer than comparison participants at identifying the scenario to which people in the videos were responding. There were no group differences in time spent looking at the eyes or mouth. The findings imply those with ASD are impaired in using mentalising skills for retrodiction.

Matched MeSH terms: Eye Movements/physiology
Fulltext Eye tracker as an implied social presence: awareness of being eye-tracked induces social-norm-based looking behaviour

Wong HK, Stephen ID

J Eye Mov Res, 2019 Aug 05;12(2).
PMID: 33828723 DOI: 10.16910/jemr.12.2.5

Human behaviour is not only influenced by the physical presence of others, but also implied social presence. This study examines the impact of awareness of being eye-tracked on eye movement behaviour in a laboratory setting. During a classic yes/no face recognition task, participants were made to believe that their eye movements were recorded (or not recorded) by eye trackers. Their looking patterns with and without the awareness of being eye-tracked were compared while perceiving social (faces, faces-and-bodies) and non-social (inanimate objects) video stimuli. Area-of-interest (AOI) analysis revealed that misinformed participants (who were not aware that their eye movements were being recorded) looked more at the body (chest and waist) compared to informed participants (who believed they were being eye-tracked), whereas informed participants fixated longer on the mouth and shorter on the eyes of female models than misinformed participants did. These findings highlight the potential impact of an awareness of being eye tracked on one's eye movement pattern when perceiving a social stimulus. We conclude that even within laboratory settings an eye tracker may function as an implied social presence that leads individuals to modify their eye movement behaviour according to socially-derived inhibitory norms.

Matched MeSH terms: Eye Movements
Hospital Universiti Sains Malaysia experience in orbital floor reconstruction: autogenous graft versus Medpor

Wajih WA, Shaharuddin B, Razak NH

J Oral Maxillofac Surg, 2011 Jun;69(6):1740-4.
PMID: 21272979 DOI: 10.1016/j.joms.2010.07.053

A normally restored orbital structure after reconstructive surgery would accelerate the return of orbital function. The aim of the present study was to compare the outcomes of 2 orbital implants: autogenous grafts and porous polyethylene (Medpor).

Matched MeSH terms: Eye Movements
Fulltext Bilateral idiopathic optic perineuritis in a young Malay woman: A case report

Ayesha Mohd Zain, Umi Kalthum Md Noh, Mushawiahti Mustapha, Norshamsiah Md. Din, Bastion, Mae Lynn Catherine

Neurology Asia, 2015;20(4):407-409.
MyJurnal

A 28-year-old Malay woman presented with severe loss of vision in both eyes associated with periocular pain on eye movement. She was completely blind at presentation and examination showed optic discs
swelling. Optic nerve imaging showed ‘doughnut sign’, characteristic of optic perineuritis. Steroid was
given over six months. Visual function improved gradually and was maintained at one year follow-up.
This case highlights the importance of differentiation between optic neuritis and optic perineuritis as
visual recovery depends on prolonged management with corticosteroid in optic perineuritis.

Matched MeSH terms: Eye Movements
The inter-relationship between magnification, field of view and contrast reserve: the effect on reading performance

Mohammed Z, Dickinson CM

Ophthalmic Physiol Opt, 2000 Nov;20(6):464-72.
PMID: 11127126 DOI: 10.1111/j.1475-1313.2000.tb01124.x

For the reading task, contrast reserve is defined as the ratio of the letter contrast of the printed letters, to the reader's contrast threshold. Acuity reserve is the ratio of the print size used for the reading task, to the reader's visual acuity. The effects of low contrast reserve on reading performance were investigated at various magnifications, ranging from 3x to 7.5x, with the field of view systematically controlled. Eye movements were recorded whilst normally sighted subjects read using the magnifiers. It was shown that with adequate contrast reserve, increasing the field of view improved the reading rate because of the resulting increase in forward saccade length. Conversely, reducing the contrast reserve slowed the reading rate by decreasing the length of forward saccades and increasing the mean fixation duration, suggesting that the perceptual span is reduced at low contrast reserve. This study also shows that when the contrast reserve is low, providing magnification higher than that required for letter recognition (that is, increasing the acuity reserve) will not improve the reading performance. Furthermore, even when the contrast reserve was high, reading rates were lower for the magnifications of 5x and higher, because increases in saccade length do not match those of the retinal image size at these magnifications.

Matched MeSH terms: Eye Movements/physiology
Exploring bedside clinical features of parkinsonism: A focus on differential diagnosis

Bhidayasiri R, Rattanachaisit W, Phokaewvarangkul O, Lim TT, Fernandez HH

Parkinsonism Relat Disord, 2019 Feb;59:74-81.
PMID: 30502095 DOI: 10.1016/j.parkreldis.2018.11.005

The proper diagnosis of parkinsonian disorders usually involves three steps: identifying core features of parkinsonism; excluding other causes; and collating supportive evidence based on clinical signs or investigations. While the recognition of cardinal parkinsonian features is usually straightforward, the appreciation of clinical features suggestive of specific parkinsonian disorders can be challenging, and often requires greater experience and skills. In this review, we outline the clinical features that are relevant to the differential diagnosis of common neurodegenerative parkinsonian disorders, including Parkinson's disease, multiple system atrophy, progressive supranuclear palsy, and corticobasal degeneration. We aim to make this process relatable to clinicians-in-practice, therefore, have categorised the list of clinical features into groups according to the typical sequence on how clinicians would elicit them during the examination, starting with observation of facial expression and clinical signs of the face, spotting eye movement abnormalities, examination of tremors and jerky limb movements, and finally, examination of posture and gait dysfunction. This review is not intended to be comprehensive. Rather, we have focused on the most common clinical signs that are potentially key to making the correct diagnosis and those that do not require special skills or training for interpretation. Evidence is also provided, where available, such as diagnostic criteria, consensus statements, clinicopathological studies or large multi-centre registries. Pitfalls are also discussed when relevant to the diagnosis. While no clinical signs are pathognomonic for certain parkinsonian disorders, certain clinical clues may assist in narrowing a differential diagnosis and tailoring focused investigations for the individual patient.

Matched MeSH terms: Eye Movements

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