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At least 19 recordsLinked to original sources
PubMed2026

Identification Matters: How Data Sharing Affects Pupil Honesty and Engagement in Universal School Well-Being Assessments.

PURPOSE: Universal well-being assessments in schools may support early identification of pupils needing mental health support. However, little is known about how privacy and confidentiality concerns influence pupils' acceptability of assessments and willingness to engage authentically. This study examined how hypothetical identification, where responses are linked to pupils and shared with key stakeholders, affects pupils' anticipated honesty and engagement, and whether known help-seeking barriers predict negative responses. METHODS: Cross-sectional data were collected from 12,377 primary (ages 8-10) and secondary pupils (ages 11-17) across 55 schools in England. Pupils reported whether their responses would change if identifiable and shared with school staff, parents/guardians, or external professionals. Responses indicating reduced honesty or likelihood of disengagement were coded as negative. Predictors were examined using mixed-effects logistic regression models, including demographics, school connectedness, and mental well-being. RESULTS: Identification and data sharing influenced pupils' anticipated engagement, particularly in secondary schools. Identification by school staff elicited the highest proportion of negative responses in both phases, whereas external professionals elicited the fewest. Most primary pupils reported they would respond authentically, while a larger proportion of secondary pupils indicated they would respond less honestly or disengage when responses were identifiable and shared. Across primary and secondary samples, low well-being, low school connectedness, and being female were associated with greater likelihood of negative response. DISCUSSION: Pupils' anticipated engagement with well-being assessments is shaped by who accesses their data, with marked developmental differences. Strengthening trust, privacy, and connectedness, and supporting pupils' autonomy, may improve the acceptability and response accuracy.

Humans↗
PubMed1979

The effect of pupil size on visual acuity in uncorrected and corrected myopia.

The effect of pupil size on the relation between Snellen visual acuity and corrected and uncorrected myopia was examined for 22 young subjects with degrees of myopia ranging from 0.75 D to 7.5 D. Effective pupil size was varied by inducing mydriasis and then placing artificial pupils of between 1.0 and 8.0 mm diameter before the eye. Both a constant chart luminance of 120 cd/m2 and a constant retinal illuminance of 2150 trolands were used. There was little difference in results for the two lighting conditions. For the corrected myopes considered as a group, maximum visual acuity occurred for 2--3 mm diameter pupils, but larger pupils reduced acuity only marginally. For the uncorrected myopes, variation in pupil size produced a large variation in visual acuity, and for refractive errors greater than about 1.5 D, the optimum pupil diameter was less than 1 mm. For uncorrected myopes of 3.0 D or less, visual acuity was nearly as good with a 1-mm pupil as for corrected myopes. The presented data are a useful guide to the clinician.

Adult↗
PubMed1979

Static and kinetic properties of the dolphin pupil.

In dim illumination, adult human pupil area becomes asymptotic at about 51 mm2 whereas the dolphin pupil achieves an area of about 70 mm2 under equivalent conditions. At moderate illumination levels (greater than 100 lx), the dolphin pupil becomes a horizontally oriented ellipse and develops a pronounced central constriction with additional light. The relative relationship between pupil area and illumination copmares closely with published human data. Rates of pupil response to step increments in illumination are very similar for the two species. Although the pupil has been proposed as a mechanism for correction of the dolphins' high aerial myopia, correlation of the laboratory findings on static and kinetic pupil properties with visually controlled aerial behaviors disclosed no special interdependence.

Adaptation, Ocular↗
PubMed1979

[The role of the pupil's size in the perception of other persons].

Studies by Hess (1975) show that the pupil serves as a source of information in perception of the emotional state of another person. Large pupils are interpreted in a positive sense. Basing on the results of Hess, the hypothesis that pupil size does not become a relevant variable in person perception until after puberty, was formed. The following result would be interpreted as supporting the hypothesis: since girls reach puberty before boys, more girls should react to pupil size than boys of the same age. 121 students between the ages of 11 and 16 years judged in several statements which of two face photos of a teacher expressed a greater degree of positive attention and esteem towards the students. The two face photos were identical with the exception of pupil size. All age groups rated the photos with larger pupils more positively. Sex differences occurred in the ratings of the 11 to 12-year-olds. Some basic differences between this experiment and that of Hess are discussed.

Adolescent↗
PubMed2025

Pupil dynamics in macaque recognition memory tasks: investigating physiological mechanisms.

Cognitive deficits are common in primates, particularly in memory and emotional processes. Rhesus monkey (Macaca mulatta), widely used in cognitive and behavioral research, are central to memory studies. The relationship between recognition memory performance and pupillary dynamics in rhesus monkeys remains underexplored. This study investigated pupil dynamics during recognition memory tasks and their physiological correlates in five sexually mature male rhesus monkeys. We measured pupil diameter and oscillatory features during tasks and analyzed the relationship between behavioral performance and physiological indicators. We found that the average correct response rate exceeded the random success level, and reaction times were significantly shorter during successful recognition than failures, highlighting their cognitive efficiency. During recognition of familiar scenes, average pupil diameter increased, while maximum change in pupil size decreased, indicating reduced cognitive load. Both the frequency and amplitude of pupillary oscillation were lower during successful trials, reflecting decreased cognitive conflict and effective processing. This change reflects a decrease in cognitive conflict and suggests that information processing was more effective. The absolute value of the pupil peak slope decreased during successful recognition, indicating more stable cognitive state. These results support that pupillary dynamics can serve as physiological markers of cognitive effort in rhesus monkeys. Future studies should investigate how stimulus characteristics influence recognition and incorporate measures, such as intracranial EEG and fMRI, to enhance our understanding of their neural mechanisms. This research supports the rhesus monkey model in cognitive neuroscience and contributes to understanding primate cognition and its physiological foundations, with implications for clinical and translational research.

Animals↗
PubMed1977

Actions of amphetamine and antagonists on pupil diameter in the chronic sympathectomized dog.

The left superior cervical ganglia were removed from 5 dogs. Beginning 30 days postoperatively, epinephrine (10 microgram/kg/min), norepinephrine (10 microgram/kg/min), and d-amphetamine (1.0 mg/kg) were infused i.v. for 10 min following either vehicle, phenoxybenzamine, pimozide, or haloperidol. Epinephrine and norepinephrine dilated the pupil and retracted the nictitating membrane of the denervated side, whereas amphetamine dilated both pupils and retracted both nictitating membranes. Phenoxybenzamine (4 mg/kg) constricted primarily the pupil of the innervated iris and completely antagonized the effects of the catecholamines on the irides and amphetamine on the nictitating membranes, but only partially antagonized amphetamine-induced mydriasis. Haloperidol (1.0 mg/kg) constricted both pupils, possessed only modest alpha-adrenergic blocking activity, and was as effective as phenoxybenzamine in antagonizing amphetamine-induced mydriasis. Pimozide (0.1 mg/kg) constricted both pupils, had no significant alpha-adrenergic blocking activity, and did not antagonize amphetamine-induced mydriasis. Pimozide and haloperidol, but not phenoxybenzamine, blocked amphetamine-induced stereotyped head bobbing. These results suggest that amphetamine produces mydriasis in the dog through a peripheral sympathetic action and also through a central mechanism involving inhibition of the oculomotor nucleus. However, the role of dopamine is not clear.

Animals↗
PubMed1979

Pupil dilation, sex of stimulus, and age and sex of observer.

10-yr.-old, 16-yr.-old, and 20-yr.-old male and female observers (ns = 10; N = 60) rated a number of male and female faces for how 'good-looking' they were. Some of these faces were identical save that in one version the pupils were larger. Pupil dilation in the photographs of males produced no significant effects, whereas pupil dilation in the female photographs caused such faces to be rated as more good-looking by the two oldest groups of male observers. The 10-yr.-old boys and the 16- and 20-yr.-old women rated the female faces with enlarged pupils as significantly less 'good-looking' than the same faces with smaller pupils.

Adolescent↗
PubMed1979

The influence of 1,3,7-trimethyl-xanthine (caffeine) on the pain-caused dilation of pupil.

The pupil dilation in man caused by pain was investigated. The pain stimulus was induced electrically. The size of the pupil was measured according to the "flying spot scanning method". The accuracy of measurement was increased by computer-assisted addition of repeated responses as well as by elimination of the, usually not considered constriction due to light compensation over Maxwellian view. The pure psycho-sensory dilation shows no initial contraction. The central stimulant 1,3,7-trimethyl-xanthine (caffeine) does not influence the course and adaption of the pupil reaction by a pain stimulus over the threshold. The pupil reaction correlates with the subjective feeling of pain. This suggests that caffeine does not influence the feeling of pain.

Adult↗
PubMed1978

A small pupil binocular indirect ophthalmoscope.

A description of a lightweight small pupil binocular indirect ophthalmoscope is presented. This instrument can be used with well dilated pupils and clear media as any stereoscopic indirect ophthalmoscope. However, the instrument can be simply and easily adjusted for usage in patients with small pupils or opacities of the media. The optical and mechanical principles employed are presented. The technique of utilization for small pupil viewing is outlined.

Dilatation↗
PubMed1978

[The effect of the pupil as aperture and field stop on the various components of the human electroretinogram (author's transl)].

The electroretinogram (ERG) was recorded in 10 normal subjects under scotopic and photopic conditions with the pupil of one eye constricted and that of the other eye dilated. The human iris, being displaced from the nodal point of the eye, acts not only as an aperture, regulating the retinal illumination, but also as a field stop, limiting the visual angle, especially for large object fields, as in Ganzfeld illumination. This double effect of a constricted pupil clearly influences the Ganzfeld ERG, not only shifting the intensity response functions to higher luminances but also diminishing the maximal responses. Control experiments with smaller test fields, which are less affected by the pupillary field-stop properties, reveal no diminution of the scotopic b-wave amplitudes. Implicit time functions, being nearly independent of the number of receptors stimulated, can be matched by taking into account the pupillary diameter and calculating the actual retinal illumination (Troland). Amplitudes, being highly affected by a decrease of responding neurons due to the angle-limiting field-stop character of the pupil, cannot be matched with regard to the pupillary diameter. This effect is most noticeable in Ganzfeld illumination for the scotopic b-wave, generated mainly by neurons of the peripheral retina, and has less effect on the photopic responses that are generated more centrally.

Adaptation, Ocular↗
PubMed1977

Pupil size after use of marijuana and alcohol.

In an experiment using ten subjects, marijuana produced a dose-related constriction of the pupil at low photopic light levels; alcohol produced no effect on pupil size. The two drugs in combination produced no change in pupil size.

Adult↗
PubMed1979

Behavior problems of educationally handicapped and normal pupils.

Male pupils identified as behaviorally disordered, learning disabled, and educable mentally retarded, as well as nonidentified normal boys, were rated by their teachers on the Behavior Problem Checklist. Analyses of the ratings indicated significant differences for pupil category, Behavior Problem Checklist dimension, and category by dimension interaction, but no significant differences for age alone or in interaction with other factors. Categories of pupils were best discriminated from one another on the basis of Conduct Disorder and Personality Problem dimensions of the Behavior Problem Checklist. Results were discussed in terms of some implications for special education and further research suggested by the present findings.

Adolescent↗
PubMed1979

[Current educational practices with multiply handicpped pupils -- a problematic approach in special education (author's transl)].

The curricula of schools for the physically handicapped have, as yet, been influenced too much by those of regular schools. Which is why at special schools, too, the primary focus of all educational and therapeutic measures is placed on a qualification of the pupils. Also those pupils who, as a result of the severity of their disability, will not be able to enter vocational training are instructed on the basis of curricula modelled for the non-disabled. The purpose of the following article is to introduce this problem complex which has been present for years but not yet received satisfactory solutions. It is hoped that the described experiences gained with the three groups of pupils will stimulate the discussion.

Child↗
PubMed1978

Pharmacological studies of the pupils in familial amyloid polyneuropathy.

Pharmacological studies of the pupils of 7 patients with familial amyloid polyneuropathy (FAP) were performed in order to demonstrate the site of the lesion. Supersensitivity to 1.25% epinephrine was observed frequently, but not to 2.5% methacholine. The lesions of the sympathetic nervous system, judging from the epinephrine and tyramine tests, were regarded as preganglionic in 2 patients and postganglionic in 4. Among 3 patients reexamined six months later, 1 had developed signs of sympathetic postganglionic disturbance and another showed a peripheral parasympathetic disturbance associated with progress of a sympathetic preganglionic disturbance. From these results it was suggested that in FAP, sympathetic abnormalities involve the pupils more often than parasympathetic disturbances, and pharmacological studies can detect the autonomic dysfunction before it becomes clinically apparent.

Adult↗
PubMed1979

Atropine versus glycopyrrolate. A study of intraocular pressure and pupil size in man.

Following control observations of intraocular pressure and pupil size, in doses suitable for pre-anaesthetic medication, glycopyrrolate (0.004 mg/kg) and atropine (0.01 mg/kg) were given intramuscularly to healthy volunteers in a randomised, cross-over fashion. No significant change in either intraocular pressure or pupil size was noted 45 min after drug administration.

Adult↗
PubMed1976

Hereditary sensory neuropathy and tonic pupils.

The clinical features of two siblings with both hereditary sensory neuropathy and bilateral tonic pupils are described. Other neurologic disorders associated with tonic pupils are reviewed. Our patients appear to represent a unique instance of the association of disorders that primarily affect the ciliary and dorsal root ganglia.

Adult↗
PubMed1979

Using color substitution pupil response to expose chromatic mechanisms.

It is well known that pupillary threshold shows a scotopic spectral behavior, even for foveal stimuli. However, when two scotopically balanced fields at different wavelengths are alternated, the pupil shows a constriction response at each transition, exposing innervation from chromatic mechanisms. Using a suitable model for pupillary innervation, this substitution response is systematically studied for different wavelengths and radiant power levels to yield (within the accuracy of the assumptions of the model) spectral threshold curves for the chromatic mechanism as indicated by the pupil. Four mechanisms have thus been identified, having peak sensitivities near 450, 525, 580, and 495 nm. We propose that these represent the blue, green, red and scotopic mechanisms as maintained before the level of the lateral geniculate body.

Color Perception↗
PubMed1979

Head injury and the dilated pupil.

The significance of the dilated pupil in head injury is discussed. History of this condition and its possible mechanisms are described. Three patient reports are presented with unilateral dilated pupil. The literature on the subject is reviewed. Finally, the diagnostic steps which may be taken to differentiate direct third nerve injury from expanding mass lesion are suggested.

Adult↗