The Effect of Amplitude Modulation on Low-Frequency Spatial Cues

12 mins read

Last Updated on September 16, 2022

In class, we studied how waves change as the amplitude increases. We drew a graph to illustrate how the energy of waves decreases as the amplitude increases. We also looked at the impact of amplitude modulation on low-frequency spatial cues. We were also asked to consider a case where the energy of waves is increasing, and the amplitude decreases.

Energy of waves decreases as amplitude increases

As we all know, the wave’s amplitude (the length between its peak and trough) is directly proportional to its energy. In this report, Tara shows how the amplitude of waves decreases as the energy of waves increases. She also shows how waves increase and decrease in amplitude. Her findings are surprising and will leave us thinking about the properties of waves and the role they play in our lives.

When a circular wave moves away from a rock drop, its amplitude reduces, as it reaches a higher surface area. This effect is caused by dispersion, which means that a top that is common at one point is different at another location. The same phenomenon is true of electromagnetic waves. As a result, as the spherical wave moves further away from its source, its amplitude decreases.

As we know, the energy of waves varies with the height of the waves, their wavelength, and the distance over which they break. Large amplitude waves release more energy than smaller waves, and larger amplitude waves fall farther than small ones. A wave with a higher amplitude is four times stronger than a smaller one. This effect is similar with ocean breakers, where the amplitude of waves churn the shore more than small ones. The larger amplitude waves lift seagulls higher than smaller ones.

Students can create scatter plots to represent the energy of waves as they study the sediment carried by the ocean. They can compare their results to the data provided by their peers and with their instructors to see which trend lines are most representative. This information will be useful in developing an explanation of the energy of waves and supporting their own ideas. This activity will help students build reasoning skills and use their knowledge to connect evidence to support their theories and make their conclusions.

If a wave’s amplitude increases by two units, then its energy is quadrupled. This is known as the inverse square law. The energy value of waves doubles with each unit of amplitude, which is what we are discussing in this report. This relationship is known as the energy-amplitude law, and it is useful in many cases in our everyday lives.

For example, high-frequency waves transfer more energy packets in a unit of time. This means that the higher the frequency, the higher the energy of a wave will transfer. And this law is even more relevant in the context of alternative energy production. While these waves are both extremely beneficial for us, they can also have a detrimental effect on our lives. For these reasons, scientists and engineers have begun examining how they can be used to protect our coastlines. For instance, they could be used as a source of renewable energy.

Modulation of amplitude modulates low-frequency spatial cues

In natural electrosensory stimulation, the amplitude of each EOD is modulated by sinusoidal waves. When two fish swim close together, these waves are detected in a similar way. Their threshold levels are remarkably different, usually between ten and hundred Hz, and are further modulated at lower frequencies, less than a few Hz. The two tones are then co-modulated, which makes detection easier.

Moreover, these effects may be due to a central mechanism that controls adaptation to loudness. Specifically, amplitude modulation cues activate central “modulation filter banks” that are activated by interplay between inhibitory and excitatory inputs. In addition, modulation of low-frequency spatial cues produced minimal changes in long-term spectral cues and the spatial distribution of excitation. These findings indicate that neural synchronization is important for maintaining loudness perception over time.

A further perceptual study of amplitude modulation in echolocation was conducted by Dankiewicz et al., but this study did not use real-time echoes. Instead, they manipulated the amplitude of each echo by applying a single amplitude modulation cycle across a fixed number of echoes. The frequency of the amplitude modulation depended on the number of dolphin emissions in a particular time interval.

In addition to amplitude modulation, this study also investigated the time between successive points on the echo sequences. Because of its limitations, this study is not comparable to psychophysical data. Therefore, it remains important to consider psychophysical data and make a direct comparison. Therefore, the study was performed to investigate the effects of amplitude modulation on the neural representation of low-frequency spatial cues.

It has been suggested that amplitude modulations influence the selection of visual spatial frequencies, but it is unknown how many. However, we know that bats use a different detection strategy than humans, which may explain their ability to detect amplitude modulations. Regardless of the perceptual mechanism, the study highlights the diversity of selective pressures that affect the echolocation system. These findings are particularly exciting and suggest that we need to investigate the role of different auditory cues in interpreting low-frequency spatial cues.

The frequency ranges at which humans detect amplitude modulation are also important in identifying the spatial cues of objects and people. We have compared thresholds for low-frequency cues using four different frequencies. Interestingly, the thresholds were quite similar to those for detecting the presence of low-frequency spatial cues in humans. The findings indicate that modulation of low-frequency cues is a powerful way to determine the level of spatial awareness.

We also determined the sensitivity of the carrier ITD and the offset threshold. The former showed that offset thresholds were lower for the onset of the stimulus than for the following cues. The result also shows that the onset of the signal had the greatest perceptual weight than the subsequent cues. These findings suggest that asymmetrical spatial cues are important for the discrimination of lateralization.

Impact of amplitude modulation on low-frequency spatial cues

Amplitude modulation can influence the central mechanisms that regulate loudness adaptation, particularly the lower frequency range, by activating the’modulation filter bank’, which might arise from the interplay of excitatory and inhibitory inputs to the inferior colliculus and ventral cochlear nucleus. The authors suggest that the increased output of neurons in the modulation filter bank may counteract these adaptation mechanisms.

In addition to studying the sensitivity of neurons to variations in intensity, AM has been used to study the sensitivity of auditory pathways. Two reviews of AM and its applications have been published. These two studies highlight a number of important considerations. For example, fast AM may not be perceived as variations in loudness, but it may induce a flutter effect that reflects additional excitation of low-frequency neurons.

In contrast, high-frequency amplitude modulation may contribute to the perception of a tone as a continuous signal. This phenomenon is associated with low thresholds. This may occur as a result of distortion products. Moreover, high modulation frequencies would be the greatest source of ITDs. This experiment, performed on 21 normal hearing subjects, measured thresholds under different conditions, a carrier frequency of four kHz and an amplitude modulation of seventy-six-hundred-hertz (SPC), as well as eighty-five-dB-low-pass masking noise and a signal level of sixty dB.

Another study showed that low-frequency amplitude modulation affects adaptation to noise, particularly when compared to pure tones. A 50%-amplitude-modulated tone, for example, was more than twice as loud after 180 s than a hundred-hundred-Hz tone. The findings suggest that modulation can affect the central mechanisms that govern loudness adaptation. This finding was confirmed by recordings of subjects’ responses to tones in noisy environments.

Studies of auditory scene processing have been conducted using both high-frequency and low-frequency amplitude modulation. The cochlea and auditory nerve convey similar temporal information, but the mechanisms underlying these processes remain unclear. In contrast, differences in temporal information conveyance remain. The cochlea is much more sensitive to low-frequency ITDs than to high-frequency ITDs.

The results of the study revealed that the peak ITD and peak width did not change during the modulation. However, the modulation did alter the response to favorable and unfavorable ITDs. In a further experiment, the same units under the same conditions responded to both types of ITDs. These results indicate that modulation can affect the processing of low-frequency spatial cues.

Similar to experiments assessing TMTF, the presence of a common amplitude modulation (AM) pattern is essential to detect the change in AM. Furthermore, the presence of an unmodulated tone does not alter the detection of AM. It should be noted that two tones with the same AM pattern may interfere with one another. As a result, the detection threshold should be lower for the comodulated tones.

About The Author

Fernánda Esteban is a food fanatic. She can't go more than a few hours without eating, and she loves trying new foods from all over the world. Her friends know that they can always count on her for a good conversation, and she's an animal lover who will never turn down an opportunity to pet a dog or cat. Fernánda also enjoys learning about random facts, and she's a social media practitioner who loves to share what she knows with others.