Topic 1: Introduction Flashcards
What is one of the primary challenges in cognitive psychology?
one of the primary challenges in cognitive psychology relates to how to go about operationalizing the mental processes we want to study
this can be particularly difficult because those mental processes are inaccessible and essentially invisible to us (we can’t touch them, nor directly observe/measure them)
cognitive researchers have therefore had to look for clever ways to make somewhat indirect inference about these mental processes on the basis of things that are accessible (i.e., measurable)
What does the classical cognitive approach involve?
measuring observable behavior (e.g., RT, accuracy, etc.)
making inferences about underlying cognitive activity
consider what this behavior says about how the mind works
What does the typical cognitive neuroscience approach involve?
measuring neural activity (and/or observable behavior)
making inferences about underlying cognitive activity
considering what this neural activity (and/or behavior) says about how the mind works
What is neuroimaging?
the development and refinement of modern imaging techniques represents a sort of paradigm shift for cognitive research
many possible applications for imaging beyond basic research have emerged (e.g., diagnostic, neurofeedback, etc.)
What are the challenges to relying on imaging techniques?
however, a reliance on imaging can also lead to various challenges
many of these can result in various kinds of limitations and confounds which, if not properly addressed, can easily create many problems with data interpretations
What is theoretical and practical significance?
producing meaningful (or in other words, worth doing) scientific work can be very complicated/difficult for lots of reasons
as a starting point, we might consider a general distinction between theoretical significance and practical significance
finding a practical application probably shouldn’t be considered a requirement for a scientific finding to be considered “meaningful”, in part because we often don’t foresee the practical applications that will eventually emerge from basic research
however, if you can connect a finding/some body of work, theory, etc. to a practical application, that can become a pretty easy argument for why it has provided a meaningful contribution
What does the study on the “Christmas Spirit” network tell us?
one example of the complexity/difficulty in producing meaningful imaging work involves a study that claims to locate a network of brain regions which may play a role in experiencing “Christmas spirit”
how should we interpret these results? Remember that results are at least supposed to be objective but interpretations are inherently at least somewhat subjective
what exactly does a statistically significant result even mean here?
does statistical significance tell you anything about the potential for the results to have any theoretical or practical significance?
how common are false positives and why is that relevant?
What does the study on the “Christmas Spirit” network show us about localization of functions?
looking at the potential for theoretical significance, while we know that localization of function is a meaningful concept that has value, we also know that there are lots of distributed representations in our brains
could we sometimes be “missing the point” by obsessively looking for a singular region associated with virtually every process/behavior. etc.?
how much does finding a region (or even network) that becomes active when presented with particular stimuli even explain (and how/when can we make causal claims about those relationships)?
once again, what about practical significance (e.g., any obvious practical applications)?
What was the Bellier et al. (2023) study “Another Brick in the Wall”?
Bellier et al. (2023) recorded neural activity while participants were listening to a song, then tried to “decode” those signals in order to recreate the song
What is the potential theoretical significance of the “Another Brick in the Wall” study?
Bellier et al. (2023) used a patient population who were already undergoing invasive neurosurgery involving having electrodes placed directly on their cortex: this allowed the researchers to do something similar to what happens with conventional EEG, though with much more precision than would usually be the case by taking measurements through the scalp
similar experiments have already been conducted to decode various forms of linguistic representations from patterns of neural activity (e.g., hearing, seeing, thinking about words) and while this is a remarkable accomplishment in and of itself, those signals were lacking potentially important properties such as rhythm, pitch, etc.
these properties are critical aspects of both musical and speech perception and the precise neural mechanisms that represent such things are still not completely understood
What is the potential practical significance of the “Another Brick in the Wall” study?
think about how artificial/robotic computer-generated speech can sound, which lacks these musical qualities
in theory, this could allow someone who has lost the ability to speak to not only communicate using words but more effectively to do so by generating patterns of speech that include those properties
any ethical concerns about knowledge/technology that may be able to “read our minds” and learn about us based not only on what we explicitly say/write but also think/feel, etc.?
What is subtractive logic?
one kind of potentially important methodological consideration relates to the fact that some kinds of analyses can obscure meaningful signal/information in the data
this approach would become known as mental chronometry, which can be used to make inferences about the differing time courses of various cognitive processes
What is subtractive logic in cognitive psychology?
consider the following experimental design, in which participants complete one of two conditions:
simple RT task: push a button after a light appears
choice RT task: push the left button if the left light turn on, push the right button if the right light turns on
in theory, both tasks involve the same simple basic perceptual a motor components, though the choice RT task adds a decision making component (which is not present in the simple RT task)
because both tasks involve the same simple basic perceptual and motor components (and the choice RT task simply adds a decision making component), subtractive logic can be used to infer the time it takes to make the decision that is required in the choice RT task (e.g., the additional component that isn’t present in the other task)
this value can be inferred by subtracting the average RT in the simple RT task from the average RT in the choice RT task
time to make a decision = choice RT - simple RT
How can subtractive logic be incorporated into imaging?
- measure activity at rest while someone is “doing nothing” in the scanner… that becomes the baseline activation
- measure activity when someone is doing a specific task you are interested in studying (e.g., reading)… that becomes the task activation
- subtract the baseline activity from the task activity to produce a signal that should be specifically related to what you’re actually interested n studying (e.g., reading)
What is a potential problem of using subtractive logic in neuroimaging?
one potential problem with the approach outlined on the previous slide became apparent when the default network was discovered
the assumption when subtracting the baseline activity was that it was neural activation that was not of any interest to researchers
even if we’re told to sit there doing nothing, our brains are constantly active and that baseline activity may actually reflect processes that you don’t fully understand
if so, you may be “subtracting the background”, which doesn’t always make sense to do
What is the default mode network (DMN)?
early research into resting state led to the discovery of the default mode network (DMN), a network of brain regions that are active at rest (i.e. when someone is not engaged in any specific task)
evidence for some form in many different mammals
associated with mind wandering in humans
likely has some adaptive functions (e.g., memory consolidation), though this is still a matter of debate
How is the default mode network an example of a problem with subtractive logic?
the discussion about the default network provides one example of why subtractive logic, through a very reasonable idea that is useful in many contexts, may (at times) introduce some unintended confounds
more generally, it also provides a basic example that illustrates the difficulty in the meaningful interpretation of imaging data
it also demonstrates why careful experimental design is so critical for producing meaningful data
