The phase of PVEP in maxwellian view: Influence of contrast, spatial and temporal frequency

Simon, Fredemann

doi:10.1016/0042-6989(92)90175-i

Cited by 14 publications

(4 citation statements)

References 23 publications

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“…The rate of modulation often used for humans and non-human primates is 7.5 or 8.0 Hz, which is equivalent to 15 to 16 reversals per second (Plant, Hess, and Thomas, 1986;Salgarello et al, 1999;Viswanathan, Frishman, and Robson, 2000). This rate should produce optimal response amplitudes over other rates of modulation, as it is the peak temporal-frequency in the human temporalmodulation function determined electrophysiologically Plant et al, 1986;Porciatti et al, 1992;Regan, 1966;Simon, 1992). Animal studies also have found the peak frequency to be in this range of temporal modulation:…”

Section: Temporal Modulationmentioning

confidence: 95%

Spatial contrast sensitivity of birds

2006

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Contrast sensitivity (CS) is the ability of the observer to discriminate between adjacent stimuli on the basis of their differences in relative luminosity (contrast) rather than their absolute luminances. Prior to this study, birds had been thought to have low contrast detection thresholds relative to mammals and fishes. This was a surprising phenomenon because birds had been traditionally attributed with superior vision. In addition, the low CS of birds could not be explained by retinal or optical factors, or secondary stimulus characteristics. Unfortunately, avian contrast sensitivity functions (CSFs) were sparse in the literature, so it was unknown whether low contrast sensitivity was a general phenomenon in birds. This study measured CS in six species of birds The quail and pigeon data obtained in this experiment fit well with existing CS data for these species. The kestrel data were not similar to kestrel data in the literature; however the data in the literature were collected from a single subject. All of the birds studied had contrast sensitivities that were consistent with their retinal or optical morphologies relative to other birds (in species for which such data exists) and seem well suited for their natural environments. In addition, all of these birds exhibited low CS relative to humans and most mammals, which suggests that low CS is a general phenomenon of birds.Explanations for this avian low CS phenomenon include a possible trade-off between contrast mechanisms and UV mechanisms in cone systems, and lateral inhibitory mechanisms that are perhaps categorically different from mammals. Lateral inhibition affects contrast gain, and has been shown to differ according to ganglion cell types, which in turn will differ in vertebrate species.

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Section: Temporal Modulationmentioning

confidence: 95%

Spatial contrast sensitivity of birds

2006

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“…Several studies have shown that peak latency is less variable than amplitude measures, both within and between subjects. [1][2][3][4][5][6] Peak latency is also a sensitive indicator of visual development, 6,7 which has been used for clinical evaluation of vision, and to study changes in attention, 8 binocularity, 9 acuity, 10,11 spatial frequency (SF) sensitivity, 12,13 and cortical aging. 14 Latency has also been used for clinical evaluation of vision.…”

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confidence: 99%

Latency Measures of Pattern-Reversal VEP in Adults and Infants: Different Information from Transient P1 Response and Steady-State Phase

Liu

Birtles

Wattam-Bell

et al. 2012

Invest. Ophthalmol. Vis. Sci.

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“…This speed was chosen since it has been found to show the earliest developing responses in infancy (Wattam-Bell, 1996) Like other VEPs, the latencies of DR responses is expected to depend on physiological factors such as myelination and axon properties (Buchner, Weyen, Frackowiak, Romaya, & Zeki,, 1994;Wood & Allison, 1981), intracortical connections (Bullier, Hup´e, James, & Girard, 1996), and feed-forward and feedback loops (Hup´e et al, 1998;Tovee, 1994). DR may also depend on head circumference (Zhao & Pan, 2008), specific stimuli conditions tested that includes different contrast, temporal frequencies (Tobimatsu, Kurita-Tashima, Nakayama-Hiromatsu, Akazawa, & Kato, 1993a;Simon, 1992), and spatial frequency (Tobimatsu, Tashima-Kurita, Hiromatsu-Nakayama, & Kato, 1993b). Attention of the participant could also affect VEP latency (Di Russo & Spinelli, 1999;Di Russo, Martinez, Sereno, Pitzalis, & Hillyard, 2002;Ling & Carrasco, 2006).…”

Section: Factors Affecting Latencymentioning

confidence: 99%

Development of visual motion processing: Phase and peak latencies of direction-specific visual evoked potential

et al. 2013

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The direction-reversal visual evoked potential (DR-VEP) latency is a key measure of the development of motion processing in infancy. However, the latency of this response has not been previously investigated. For other stimuli, both the latency of an initial peak and a latency measure calculated from steady-state phase as a function of frequency have been shown to be important and distinctive indicators of development. The latter measure is hypothesized to reflect the time course of cortical processing beyond the initial response that generates the first positive peak. DR-VEP was tested in 61 adults at 1-16 reversals per second (r/s) and 76 infants (age 7.7-79.0 weeks) at 2-8 r/s. In addition to measuring the transient peak latency at 1-3 r/s, latencies from the gradient of phase against reversal rates were also calculated from steady-state recordings at 1-16 r/s. For both adults and infants, peak latencies were similar for 1-3 r/s, while the calculated latency was substantially longer. Thirty-nine percent of adults and 17% of infants showed additional early transient peaks. We suggest that this early peak may reflect activation of extrastriate areas by motion, by a route that bypasses V1. While both transient latencies were similar to adult values around the onset of DR responses at 10 weeks of age, the latency calculated from phase values did not asymptote to the adult value of 207 ms until around 30 weeks. The overall time course of the response to direction reversal is prolonged compared with the transmission delay that generates the initial transient peak, presumably reflecting feed-forward, lateral, and recurrent connections that refine and elaborate the directional response of cortical neurons. While the peak latencies stay relatively unchanged throughout development, the dynamics of further motion processing are not mature until after 8 months of age. These measures may prove important indicators of motion development in future clinical evaluations.

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The phase of PVEP in maxwellian view: Influence of contrast, spatial and temporal frequency

Cited by 14 publications

References 23 publications

Spatial contrast sensitivity of birds

Spatial contrast sensitivity of birds

Latency Measures of Pattern-Reversal VEP in Adults and Infants: Different Information from Transient P1 Response and Steady-State Phase

Development of visual motion processing: Phase and peak latencies of direction-specific visual evoked potential

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