All of the threads for this selected topic
In the reading, it is stated that: “one mechanistic interpretation of the claim that perceptual experience falls routinely at varying positions along a stimulus-imagery continuum is that bottom-up stimulus and top-down recall-related signals are not simply coexistent in visual cortex, but perpetually interact to yield percepts of ‘probable things’.” Based on this, what would be the effect of a temporal silencing of recall signals when a weak bottom-up stimulus, that is not enough to activate the neural circuitry for an associated stimulus, is presented? Would this lead to a set of uninterpretable percepts because recall is not possible? Could this “new/unfamiliar” stimulus be learned such that future presentation of it, or a relatively similar stimulus, elicits a recall signal when no silencing is performed?
In figure 5 of the Albright paper, the image initially doesn’t look like anything we can make sense of. After viewing figure 8, then going back to figure 5, we can now see the man in the image. It’s very difficult (or impossible) to go back and just see random splotches again. Is it possible to “undo” or suppress the influence of top-down signaling on our perception?
In associative recall, if A is associated with B, and when we perceive A, what is recalled? The experiment in the paper seems to suggest it is the stimuli that were originally associated with A. However, association is a kind of learning, so it should have some abstraction beyond the original stimuli. Does that mean we are also able to recall similar stimuli to B, or the average of similar stimuli to B?
Do vivid visual dreams elicit similar patterns of activity and/or activate the same brain areas, as either retinal stimulation or (conscious) explicit imagery?
In the experiments, monkeys learned to associate up and down motion with up and down arrows. If they had been shown the stimuli in an inverse manner, e.g. down motion matched with an up arrow and viceversa, would they have then associated down motion with an up arrow? The shape of an arrow has some cues that suggest the idea of where it points to, so I wonder if those cues would have prevented the monkeys from learning it the opposite way, or if they are not that strong and can be bypassed.
Albright makes a compelling argument for how memory influences visual perception, but does not consider how other sensory inputs alter the visual perceptual experience. I wonder how other sensory inputs affect visual perception, and whether these would be more or less salient than the influences of memory.
From Albright's paper "This review has focused on vision... There are nonetheless good reasons to believe that the same principles for associative recall and perception pertain to all senses. Moreover, these principles apply well to interactions between sensory modalities." How do other senses impact visual associative learning? And why hasn't the author taken into account the interactions between the different senses and their impact on visual perception?
What are the neural mechanisms that allow for generalization and discrimination between visual stimuli of the same category or different categories, respectively? For example, if a monkey was trained on the arrow/moving dot task mentioned in the Albright (2012) reading, would they be able to generalize the up arrow to an arrow pointing up with different dimensions/shape, color, etc.? If so, what mechanisms would allow for this generalization? Similarly, what neural mechanisms allow for discrimination between potentially similar visual stimuli (such as snow and mica)?
The Albright paper suggests that "the ‘‘impression’’ (the retinal stimulus) is merely a spark for associative pictorial recall," and one's memories associated with retinal stimulus are essential in determining what they perceive. This seems to imply that people with memory problems, like those that have retrograde or anterograde amnesia, must perceive the world in a different way. To what extent is this true?
Submit New Thread
Only the replies to the one thread you selected
Select a thread on the left to view the conversation.