PY2505.5 ~ {Concept Development and Critical Evaluation Workshop}
concept development
the process by which individuals, particularly children, form and refine mental representations of ideas, objects, or categories + influences how we perceive, categorize, and respond to the environment
abstract concept
tied very closely to the idea of categories whereby lots of diff things belong to one particular concept because they have shared + common features which helps identify them
why is an abstract concept described as 'abstract'
the concept is like a mental representation for the category, the abstarct is because one person's concept of a dog is not tied to one particuar example of that category
why do we need concepts
allows ua to recognize + respond accordingly to new examples e.g a dog = if you like them you can go say hello if you don't you might run or avoid
reduces diversity [so you see diff breeds of dogs don't have to relearn all the properties]
allows fororganized storage + retrieval of info
Mandler's model of the adult semantic system
there are 3 main assertions
1. fundamnetal distinction within the sematic system is animal vs non-animal
2. semantic system is organised hierachically
3. semantic system is 'organised categorically from its inception' [must to some degree be dependent on language]
object examination task [familiarisation phase]
children sit independently + hold and manipulate 1 object independently from 1 category at a time, used to measure categorisation from 6-12 months
object examination task [test phase]
you either hand the child a new example of that old category or you hand them an objet from an entirely new category and what we're interested in is how long kids spend handling these 2 diff types of objects
what are we testing in object examination task
comparison of handling time for object from new category vs old, the idea is that if they handle the diff cat for longer that might suggest that this new cat is particularly interesting to them because they've recognized that they've been handed something completely new
object examination task [results]
infants between 7-11 months made distinctions between animals, vehicles and furniture
9-11 month olds can even distinguish within the same cat [but only if they are really diff]
only 11 month could distinguish between dogs + cats
object examination task [conclusions]
suggests young infants have a conceptual understanding of the cats of animals vs non-animals
suggests conceptual understanding may develop before acquisition of the language to describe cat
object examination task [explanation for conclusions]
a toy dog + toy car are perceptually diff so the distinctions could be made based off of these features
Piaget and perceptual diff
argued that kids really explore + learn about the world using their sensory + motor processes [no abstract concepts until 2-3 years] he assumed that language is necessary to form conceptual cat
the importance of knowing a Dodo is a bird - Gelman & Coley (1990)
asked 2 year olds questions about typical + non-typical members of familiar cats [i.e birds so eagle falcon and chicken/ flamingo [atypical] and researchers would ask 'does this live in a nest']
the importance of knowing a Dodo is a bird - Gelman & Coley (1990) [results]
for typical cat members the majority of 2 year olds were able to say 'yes this lives in a nest' but for the atypical they generally didn't agree that this bird lived in a nest
the importance of knowing a Dodo is a bird - Gelman & Coley (1990) [when they changed it]
changed the question and asked 'this is a bird, does this bird live in a nest' after the kids received this info they were able to extend the properties of that particular cat to this atypical member [69% of the time]
Warrington & Shallice (1984)
first presentation of a small group of patients who had a very similar pattern of brain damage within the TL [due to herpes simplex virus + caused inflammation in their brains].
Warrington & Shallice (1984) [1st patient]
JBR - 23 year old man
his perceptual skills were intact [could match usual + unusal view photos] + fluent speech + no problem naming colours shapes letters
Warrington & Shallice (1984) [2nd patient]
SBY - 48 year old man
very similar to JBR in terms of behaviour and pattern of brain damage
Warrington & Shallice (1984) [results for words]
JBR - identified 8% of living things + 79% of non-living
SBY - identified 0% of living things + 52% of non-living
Warrington & Shallice (1984) [results for pics]
JBR - named 90% of non-living + 6% of animals and plants
SBY - named 75% of non-living + 0% of animals and plants
Hillis & Caramazza (1991)
JJ - 67 year old man
similar pattern of brain damage to JBR + SBY, + severe difficulty naming pics from all cats apart from animals + 100% when naming animals + 60-70% when naming fruits, veg, food, transportation, clothing, body parts, furniture
category specific disorders
selective loss of knowledge [specific deficits] within a specific category or specific concept
Carmazza & Shelton (1998)
semantic memory is organised categorically + evolutionary pressure caused the development of innate hardwired specialized subsytems [can be selectively damaged] to do woth living things
caveats
case studies [low number of people so not representative] + not always clean dissociation + progressive disorders can change from an initial deficit for living things to a deficit for non-living as semantic memory deteriorates + other factors may explain the processing diff
basic level concepts + subordinate level
dog = basic level + more fine grained cat within the concept of a dog which is the subordinate level
superordinate
domain level cat = broader cat that the basic level concept belongs to so a dog is an animal
(Rosch & Mervis, 1975)
we learn basic level concepts first before superordinate level concepts [so dog before animals]
(Mandler et al., 1991)
we learn about concepts hierachically, so top down where we learn superordinate cat then more fine grained cat the subordinate [so animal then dog then breeds]
sequential touching
18 + 24 + 30 month olds and thwy were sat in front of 8 objects from 2 diff cat and they measured the order in which children touched these objects as they're interacting with them; so if they touch objects from the same cat more often than by chance we assume that the infant has categorised these objects as belonging to the same cat
what are we testing using the sequential touching task
is there a hierarchial order in which we develop our understanding of concepts [at diff ages]
sequential touching task results
18-30 months are able to draw distinctions + at 18 months there was little to basic categorization [so dogs vs horses]
at 24 months only 50% were making basic level cat
semantic dementia
usually begins with an inability to gemerate certain words + progresses with increasing difficulties in word comprehension + generation + recognition
patients with this disorder retain ability to speak quite fluently + ability to remember day to day events [episodic memory]
Hodges, Graham, & Patterson (1995)
JL - diagnosed with semantic dementia assessed over 2 years
initially could name animals and household objects, but not specific instances, as disease developed, JL produced the most prototypical responses (cat, dog, horse), but other animal labels lost from his vocabulary + at one stage, all land animals were named either cat, dog, or horse + non-living
items were frequently described in terms of their broad use or function + living/man-made distinction preserved for most of the study, but by the lastsession, 50% of responses no longer respected this boundary
Hodges study [conclusion]
JL seemed to be losing memory from the bottom up, conceots that were retained the longest were those broad or superordinate level concepts [kids seem to be learning from top-down so first in last out]
early categorical organisation [Johannson]
habituation paradigms
biological vs non-biological motion [movement isn't natural its more mechanical]
[Johansson Motion Perception] stimuli portay human movement using just dots
early categorical organisation
infants are shown repeated videos of non-biological motion and at some point they will habituate ad get used to it and probably lose interest and look away from screen after this occurs we change stimuli so they now see biological motion and they dishabituate and become interested again
Bertenthal et al., 1985, 1993 [results of habituation]
3-5 months dishabituated when they switched from non-biological to biological motion which suggests that they were able to see that there was a diff in stimuli [wihtout somehting showing stimuli is changing]
possible reasons for animate + inanimate distinctions learned very early on in life
innate knowledge + innate predisposition or interest [evolutionary pressures] + very distinctive [they just look very diff so perceptual concepts]
Mandler's interpretation of ECO
innate predisposition to be interested in animate things is not necessary to explain infant data, they may be initially attracted to moving objects because of limitations of their perceptual system [poor acuity in early months so motion might be asier to see]