7: The Speaking Brain 1 Flashcards
What does a common language signify about human perception?
We all have a common representation of the world around us
Example of animals using langauge?
Washoe - ape who learnt 200 manual signs
Koko - 1000 signs which she could combine in complex ways
Kanzi - learnt arbitrary lexigrams flexibly
What were some of the limitations of Washoe the ape’s language?
evidence of overgeneralization - eg hurt for tattoo
combined words for unfamiliar objects - eg water bird for duck)
researchers were very attached to these apes so they could’ve been too optimistic about their communication
signs are quite obvious, actions you might make anyway, unlike words which are arbitrary
What were the limitations of Kanzi the ape’s language?
arbitrary language linked to food, not communication in general
define: syntax
the arrangement of words and phrases to create well-formed sentences in a language.
What distinguishes syntax from language?
Syntax is using language correctly, but to really use language you must understand the semantics (meaning) and thought content
Which study shows that syntax doesn’t equate to semantics
Chinese room experiment
What is the semantic memory?
conceptual knowledge of the world
where is the neural base of the semantic memory?
temporal lobes
What were the ERP results for a semantically correct vs incorrect word in a sentence?
correct = no peak/result
incorrect = N400 peak
At what age is the N400 peak present?
yes, it is present from 9 months
What is the N400 peak used to investigate?
semantic representations in the brain
define: concepts
cognitive constructions that represent classes of things, events or ideas
How are concepts organised in the brain?
In a network by similarity/relation
How is the N400 peak used to measure spreading activation?
N400 peak most pronounced for unrelated concepts, then related, and not there for expected
What is the amodal model of semantic memory?
features are represented as an abstract knowledge
not tied to sensory or motor output
they are independent of input or output modality
why was the semantic memory thought of as amodal?
because it can be accessed from so many different sensory inputs (spoken, written etc) so there must be an asensory component linking all these representations
Problems with the amodal model
symbol grounding problem - if each word needs to be defined by other concepts, definitions become very complicated, how would you start to learn any concepts?
solution to the symbolic grounding issue
grounded concepts/features - concepts are not defined in terms of each other, but in terms of our experiences and interactions with the world
What is Allport’s model of semantic memory
concepts are distributed over several distinct brain areas (eg phone = motor, auditory, visual)
What area of the brain is used in category-related activity?
ventral occipito-temporal cortex
occipital = visual info
temporal = semantics
What were MRIs of naming vs viewing vs answering questions on animals like?
similar activity in the same area for every mode
What are category specific deficits?
patients with brain damage who can’t name specific types of things (eg can’t name animals but can name fruits)
What is the emergent theory of category specificity?
Different categories rely on different types of characteristics (eg animals are categorised by looks (sensory areas) & tools are categorised by function (motor areas))
What is the innate theory of category specificity?
the brain is built ready for these concepts, not with these concepts
How does congenital blindness provide evidence for innate category specificity?
blind people still have similar activations to seeing people (even in the visual areas)
What does Adam’s (Farah & Rabinowitz, 2003) case study on brain injury on day 1 show?
Selective impairment of knowledge of living things in later life - shows an innate distinction between living & non-living concepts in the brain
What are the 2 models of how features are organised in the brain?
hierarchical vs non-hierarchical
What are the 2 theorised formats concepts take in the brain?
Modal (grounded) vs amodal
What are the 2 category specificity theories
Emergent or innate
what does the N400 peak in 9 month-olds tell us about their language development?
Infants understand the meaning of some words
what modulates the N400 peak for language?
N400 was modulated by the semantic connection between the expected and presented word
Semantically related words elicited smaller N400 compared to semantically unrelated words
what is an example of an amodal model of semantic memory?
hierarchical model
define: grounded cognition
Object representations are not limited to a discrete area, but rather are widespread and overlapping
how do category specific deficits evidence the innate nature of categories in the brain?
When brain damage patients lose a specific area of knowledge (eg naming animals) it suggests there are hardwired areas for these concepts
are category specific deficits amodal?
yes - someone won’t understand hearing/ reading/ seeing an image of a lion
what is the criticism of congenital blindness as evidence for innate category specificity in the brain?
blind people can still learn about shape by tough and moving through things so it’s not as if they have no representation for the shape of objects
