BACKGROUND Post mortem brain tissue data and animal modeling work indicate cholinergic disruptions in autism. Moreover, the cholinergic system plays a key role in the early neurodevelopmental processes believed to be derailed early in life in individuals with the disorder. Yet, there is no data from human infants supporting a developmentally important role of this neurotransmitter system. Becau...

We examined effects of diabetes mellitus (DM) on the pupillary light reflex (PLR). Phasic pupillary response to a single light stimulus (200 ms) (pPLR) and to continuous sinusoidal stimuli with four different frequencies (0.1, 0.3, 0.7, 1.3Hz) (cPLR) were examined in 52 DM patients and 21 control subjects. We asked: does recording and frequency analysis of cPLR together with short time fourier ...

Pupil responses of adults to near visual demands are well characterized but those of typically developing infants and children are not. This study determined the following pupil characteristics of infants, children and adults using a PowerRefractor (25 Hz): i) binocular and monocular responses to a cartoon movie that ramped between 80 and 33 cm (20 infants, 20 2-4-yr-olds and 20 adults particip...

Much psychological research uses pupil diameter measurements to investigate the cognitive and emotional effects of visual stimuli. A potential problem is that accommodating at a nearby point causes constrict. This study examined what extent accommodation confounder in pupillometry research. Participants solved multiplication problems different distances (Experiment 1) looked line drawings with ...

The Five Digits Test (FDT) is a Stroop paradigm test that aims to evaluate executive functions. It is composed of four parts, two of which are related to automatic and two of which are related to controlled processes. It is known that pupillary diameter increases as the task's cognitive demand increases. In the present study, we evaluated whether the pupillary diameter could distinguish cogniti...

The purpose was to compare resting pupil diameter in darkness and light, and the pupillary darkness and light reflexes between a group of patients with Alzheimer's disease and a group of healthy old people. Nine medication free patients with Alzheimer's disease and nine healthy control subjects, matched for sex and age with the patients, participated. There were six men and three women and the ...

We measured apparent accommodation in 42 pseudophakic eyes (34 patients) after implantation of posterior chamber intraocular lenses. The mean apparent accommodation was 2.03 +/- 1.03 diopters. The mean accommodative power of 16 phakic eyes used as controls was 2.91 +/- 1.29 diopters. The diameter of the pupil appeared to be the most important factor in apparent accommodation--the smaller the pu...

activity measured by reflected infra-red light. PHYSIOL. BEHAV. 28(5) 851-854, 1982.-A simple, reliable and inexpensive device for continuously monitoring pupillary changes is described. It is an improved version of a device first suggested by L. Stark. Infra-red light is transmitted to the iris and reflected back onto the receiver. Consequently, the device is effective only if the eye is immob...

The current study examined the extent to which pupillary responses (both pretrial baseline and phasic responses) would accurately track lapses of attention as predicted by theories of locus coeruleus norepinephrine (LC-NE) functioning. Participants performed a sustained attention task while pupil responses were continuously recorded. Periodically during the task, participants were presented wit...

Future human-computer interactions could be enhanced by enabling the computer to detect the user‟s emotional states (e.g. stress), and adjust its interaction behavior appropriately. However, providing the computer with the ability to detect important changes in the user‟s affective state is a challenging problem. We propose that increases in sympathetic activation which typically accompany the ...