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Short answer Yes, the flickering of a light bulb may be noticeable, and yes, that's directly related to the mains frequency. However, since the flickering of a bulb is about two times higher than the temporal limits of our visual system, it is unlikely to be perceivable. Background The temporal resolution of the visual system can be quantified in a ...


10

Short answer The detection threshold of static indentation stimuli on the palm of the hand is approximately 10 to 40 micrometers, dependent on the exact location under investigation. Background The sensitivity of a sensory system can be expressed as the detection threshold. This threshold is in psychophysics generally defined as that stimulus level where, ...


8

A lamp flickers at 2x the mains frequency, i.e. 100 or 120 Hz, and that is typically not noticeable to human eyes. It is visible to chicken and insects. That being said, a low quality lamp or a lamp at end-of-life may also flicker at 50 or 60 Hz, and you will notice. It depends on the brightness, so an area illuminated by the lamp may not seem to flicker. ...


8

In this instance, I would say your attention has been adjusted, not your ear's ability to perceive sound. Our ears don't have a control setting or a means of adjusting incoming sound levels (though I'm certain when an ambulance with loud siren drives by, we all wish we did). What you are experiencing is a prioritization of the sound by your brain in ...


5

Short answer Perceived tinnitus pitch tends to resemble the frequency content of the loud sound that induced the tinnitus. Background Solid, laboratory-controlled studies to the perceived pitch of temporary, noise-induced tinnitus ("ringing in the ears") are ethically questionable, because researchers have to deliberately expose study subjects to ...


4

Short answer The main limitation to frequency discrimination is loudness. Background The cochlea is tonotopically organized - it basically acts as a Fourier transformer, where different frequencies are analyzed on a place map (Fig. 1). Frequency tuning of cochlear hair cells is mainly limited by sound intensity. The louder a pure-tone sound stimulus gets, ...


4

There are limits to what a sensory system can detect, which is called the detection threshold. To determine the detection threshold psychophysical methods can be used. A straightforward way to determine the detection threshold is with a yes/no task, where the subject receives stimuli with various intensities. An arbitrary point, mostly the 50% correct-rate, ...


3

Let's say there is a point source of light (it could be a lamp or a highly reflective object) that undergoes large, rapid intensity changes, say 50-100 times a second. If you quickly move your eyes while it's in your field of vision, it will trace out a path across your retina. Some sections of this path will receive little light, while others will receive ...


2

Short answer I can be 75% sure that the lights are synchronized within 0.02 - 0.2 seconds of one another. Background Interesting question, but hard to answer! Because it has been unanswered for quite a while I will try to formulate an answer that may provide an approximate value for the minimal asynchrony perceivable. The temporal resolution of the visual ...


1

You trespass upon a question as old as antiquity: what properties constitute consciousness? The best means to respond to the question concerns a metaphysical answer and an answer in modern biology We can perhaps divide consciousness into two categories: contiguous thought from past experience and identity and secondly, self-awareness. The reputed example ...


1

The term noise can mean a number of different (more or les related) things is used in a number of different fields such as signal processing, psychology and statistics. Outside of its context, it is impossible to say for certitude what you professors were referring to. The quotations below come from wikipedia > Communication noise, wikipedia > Statistical ...


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