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September 1

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Affective "clipping"

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In signal processing, clipping is the phenomenon where a signal goes undetected because it is in phase with another signal that already drives the detector to its limit. What is the equivalent phenomenon in affective psychology called? An example of it would be that a controlled study exposes the experimental subjects to stimuli x+y and the control subjects to only y, but their reaction to y saturates all the affective dimensions that x affects, and thus both groups respond the same, and the researchers incorrectly conclude that the subject population is insensitive to x (especially likely when that population's sensitivity to y has been underestimated, or when the exposure to y was inadvertent). What is this called? Also, is it known whether such a phenomenon is relevant to the management of autism-spectrum disorders? NeonMerlin 06:23, 1 September 2017 (UTC)[reply]

The term 'Clipping' is normally reserved for analogue systems. Yet, this sound like Information overload. Something that people diagnosed has having asperger's appear to suffer from. It is not so much slow mental processing, rather the reverse, where they are aware of all the stimulus from their senses (and past memories) all at once. A gift (and sometimes burden) that us lesser mortals don't posses.Aspro (talk) 11:58, 1 September 2017 (UTC)[reply]
In my experience this sort of thing is usually referred to as a ceiling effect (statistics). Looie496 (talk) 13:37, 1 September 2017 (UTC)[reply]
I would say in your example that the signal of the response to x is "swamped" by a larger response in "y". Here [1] is a book that discusses signal swamping in regards to human hearing. Hannington_transmitting_station uses "swamped" in the same context for radio signals. I can't find any good coverage of this concept on WP. Saturation has some leads, but nothing quite like what you're describing of "I can't see the response this one signal because there is another stronger signal that is masking it". The ceiling effect mentioned by Looie can also cause this kind of swamping, but in my scientific experience "the signal was swamped" is a more general phrase that is widely understood. SemanticMantis (talk) 14:15, 1 September 2017 (UTC)[reply]
They are different things. A ceiling effect occurs when a measured parameter "hits the ceiling" in some sense and therefore is unable to rise any more. It doesn't really have anything directly to do with the size of the signal. Looie496 (talk) 14:40, 1 September 2017 (UTC)[reply]
Clipping is a phenomenon in an analog electronic amplifier or signal processing system where the amplitude of the input signal reaches the threshold of what one of the system's devices can handle before gross distortion sets in. All systems distort input signals in that they don't faithfully follow the variations in the input signal, but here we are talking about a situation where the device (transistor, tube) saturates so that it can no longer produce output that increases with the increasing level of signal and cuts off the highest values, grossly distorting the signal. The device literally clips off the tops of the waveform, hence the name "clipping". The phenomenon has nothing to do with two signals being in phase, and therefore the analogy used by the OP is not appropriate. Akld guy (talk) 20:56, 1 September 2017 (UTC)[reply]
I think it does. If we add a small square wave that is in phase to a square wave that is only just clipped we will see no change If it is perfectly out of phase we will see maximal change.
All the best: Rich Farmbrough, 12:56, 2 September 2017 (UTC).[reply]
That is a special case of clipping in which the clipping (of the larger signal) has already occurred. So it's not a definition as claimed by the OP. Akld guy (talk) 13:24, 2 September 2017 (UTC)[reply]