Thread: Audio memory

My frustration at remembering bird songs has led me to think about how much better our 'visual memory' is than our 'audio memory.' Why is this? In general does it depend on which sense is stronger, or does it come down more to brain function? Any information on this topic would be appreciated.

IIRC, it has to do with the brain space devoted to the stimuli type. There's more cortex devoted to visual memory and signal processing than there is for echoic memory and auditory signal processing. Through selection, I suspect that there was a greater advantage to interpreting visual stimuli than with interpreting auditory stimuli.


http://en.wikipedia.org/wiki/Visual_memory
http://en.wikipedia.org/wiki/Echoic_memory


Also, don't forget that it's hardly universal. Many people are born with stronger memories for sound than vision, or even other types of perceptual stimulus.

Phenomena such as absolute pitch (or perfect pitch) seem to be based on recall of what we might call audio memory. Thing is, although perfect pitch seems to be more prevalent among certain ethnicity, that breaks down when members of different ethnic groups are raised in other cultures. That suggests a cultural influence dominating in that case, rather than a genetic one. Might be oversimplifying to equate pitch memory with echoic memory in general though.

What is interesting is how many more bits of data are required to faithfully reproduce sound as opposed to video. Our analysis of sound is very sensitive. Visual info (especially the color) not so much.

MW

All very interesting, thanks. So given what you said, TheBiologista, do you think that perfect pitch could be learned (I'm not saying easily)?

inow, I was thinking that too...evolution would probably favor a stronger memory for visual stimuli than auditory. Though that makes me wonder if anything has been done to study different sensory memories in different species. Anyone know if, for example, dogs have a better memory for olfactory stimuli?

MeteorWayne, is that to say that perhaps the brain takes more training and repetition in order to reproduce complex sounds? And what do you mean by "Our analysis of sound is very sensitive."? Do you just mean that we are able to detect greater detail and variation in sounds than in sights? If so, does that mean that our hearing is stronger than our sight? If that's the case, I find that interesting because it would seem that a memory for the stronger sense would be favored...though I suppose stronger doesn't necessarily mean more important.

Check out links like this to get a better feel for how sensation and perception comes into memory. Usually, there is an emotional component which magnifies and reinforces the memory (you may have heard of "flashbulb memories").

http://www.livescience.com/8426-brai...-revealed.html

The researchers further showed that the auditory, visual and olfactory cortices each store memories related to the specific sense they process. Lesions in the olfactory cortex did not prevent trained rats from remembering to associate a sound with the fear memory.

Experiments even revealed that the sensory cortices store information specific to the emotional meaning of the sound, sight, or smell.

Rats startle when they first hear a sound, regardless of whether it's linked to a scary event. But eventually, in a process called habituation, they grow accustomed to it. The team wanted to find out if these sensory memories that didn't involve fear were still stored in the secondary cortices. So they habituated the rats to a sound with no electric shock. One month later, lesions were made on the rats' secondary cortices for all senses. The lesioned rats still didn't startle upon hearing the sound, suggesting the secondary cortices only store memories if the stimulus is tied to an emotion. These sensory memories must be stored in another brain region, the researchers figure.

The researchers note the secondary cortices are likely not the only regions involved in storing emotion memories tied to the senses. Other areas, such as the amygdala, thought to play a key role in processing fear, could participate as well.

To your question on studies of memory in animals, and whether (for example) dogs can be shown to have better memory for olfactory senses, I'm not too sure, but suspect they are available. Perhaps you can learn more with information about animal cognition, such as in the memory section of this link:

http://en.wikipedia.org/wiki/Animal_cognition


My limited knowledge suggests to me that the question is less about memory and more about primary sense for the organism. If the primary sense of a creature is vision, then they will have stronger memory for visual information. If their primary sense is sound, then they will have stronger memory for auditory stimuli. If their primary sense is scent, then they will have stronger memory for olfactory stimuli.

However, there's nothing hard or fast, and each will exist along a spectrum... even within a given species there will be differences in ability (variety just like with humans).