Cognitive Science Colloquium
Spring 2015
All meetings take place on Thursdays, 3.30-5.30 pm in Bioscience Research
Building 1103, unless otherwise noted.
February 5 Noah Goodman (Psychology, Stanford University).
Title: Uncertainty in language and thought
Abstract: Probabilistic models of human cognition have been widely
successful at capturing the ways that people represent and reason with
uncertain knowledge. In this talk I will explore the ways that this
probabilistic approach can be applied to systematic and productive reasoning --
in particular, natural language pragmatics and semantics. I will first describe
how probabilistic programming languages provide a formal tool encompassing
probabilistic uncertainty and compositional structure. I'll illustrate with a
examples from inductive reasoning and social cognition. I will then present a
framework for language understanding that views literal sentence meaning
through probabilistic conditioning and pragmatic enrichment as recursive social
reasoning grounded out in literal meaning. I will consider how this framework
provides a theory of the role of context in language understanding, focusing on
examples from implicature, vague adjectives, and
figurative speech (hyperbole and irony).
February 12 Michael Platt
(Cognitive Neuroscience, Duke).
Title:
The Biology of Strategic Social Behavior
Abstract: Most primates seem
specialized for social life, yet how biology shapes complex social behaviors
remains poorly understood. To address this gap, we study the biology and
behavior of rhesus macaques in both the laboratory and the field. Recent work
in the lab shows that monkeys favor giving rewards to another monkey,
particularly if he is more familiar or subordinate, rather than give the
rewards to no one. Oxytocina hormone implicated in social bondingmakes
monkeys more giving. Finally, giving behavior selectively activates cells in
medial frontal cortex, an area previously implicated in empathy in humans. In a
separate study, we found inactivating this area impairs social learning. By
contrast, when monkeys play a competitive game against each other, they rapidly
develop unpredictable behaviors that serve to hide their intentions. Planning
deceptive feints activates a population of neurons in the lateral frontal
cortex, an area linked to deceptive planning in humans; inactivating these
cells impairs deceptive planning. In the field, we find that intraspecific
variation in social behavior and cognition has fitness consequences and
emerges, in part, from genes that regulate neuromodulatory
function. Together, our findings suggest deep homologies in the biological
origins of complex social function in primates.
February 26 Jesse
Snedeker (Psychology, Harvard University).
Title: Clean Mapping: A
sketchy story about how conceptual structure could shape language acquisition
and some experiments suggesting that it just might be true
Abstract: To acquire syntax, children must map sentences to their
meanings (structured conceptual representations). If these conceptual representations are
available prior to language, have a similar structure to the syntax, and have
the right degree of abstraction, then this learning process could be pretty
painless.* I'll discuss an apparent
counter-example (psych verbs, where meaning and form seem to diverge) and show
how it actually supports the hypothesis.
Then Ill present some studies that explore the conceptual pieces that
make up verb meanings and their connection to the cognitive capacities of young
infants. The methods that are used
include eye-tracking, novel word learning, training studies, large-scale
internet based research, and an infant imitation paradigm.
* Many generative linguists
work in a framework theory where what I call conceptual structure is construed
as an early part of syntax and what I call syntax is, in whole or part, an
interface with phonology. Thats fine,
with careful translation we still ought to be able to communicate.
March
5 Nancy Kanwisher (Psychology,
MIT). Note: visit cancelled / deferred to next academic year.
Title:
Abstract:
March
12 Jeffrey Lidz
(Linguistics, Maryland).
Title:
On the proper treatment of
experience in language learning
Abstract:
A common pivot in debates about the nature of human language concerns the role
of experience in shaping language development. While many have found young
learners to be prodigious statistical learners and to display clear effects of
quantity and quality of input on their ultimate language outcomes, others have
focused on cases where the input is impoverished relative to the ultimate
acquired knowledge. In this talk, I examine the properties of the learner that
make input informative, providing a bridge between these two research
traditions.
Note: the talk by Giorgio Vallortigara (Mind/Brain Sciences, University of
Trento, Italy) that was scheduled for this date is cancelled / deferred to next
academic year.
April
9 David Poeppel (Psychology, NYU).
Title:
Specialization for speech and structure for language
Abstract: I will discuss two new studies from my lab that focus on
general questions about the cognitive science and neural implementation of
speech and language. I come to (currently) unpopular conclusions about both
questions. Based on a first set of experiments, using fMRI and exploiting the
temporal statistics of speech, I argue for the existence of a speech-specific
processing stage that implicates a particular neuronal substrate (the superior
temporal sulcus). In a second set of experiments, using MEG, I go on to develop
how temporal encoding can form the basis for more abstract, structural
processing. The results demonstrate that, during listening to connected speech,
cortical activity of different time scales is entrained concurrently to track
the time course of linguistic structures at different hierarchical levels.
Critically, entrainment to hierarchical linguistic structures is dissociated
from the neural encoding of acoustic cues and from processing the
predictability of incoming words. These results demonstrate syntax-driven,
internal construction of hierarchical linguistic structure via entrainment of
hierarchical cortical dynamics. The conclusions that speech is special and
language syntactic-structure-driven provide new neurobiological provocations
to the prevailing view that speech is hearing and that language is statistics.
April
23 Gerry Altmann (Psychology, University of Connecticut).
Title:
Representing objects across time: language-mediated event representation.
Abstract: Language
is often used to describe the changes that occur around us changes in either
state (I cracked the glass
) or location (I moved the glass onto the
table
). To fully comprehend such events requires that we represent the
before and after states of the object. But how do we represent these
mutually exclusive states of a single object at the same time? I shall summarise a series of studies, primarily from fMRI, which
show that we do represent such alternative states, and that these alternative
states compete with one another in much the same way as alternative
interpretations of an ambiguous word might compete. These studies also show
that whereas the representations of distinct but similar objects (e.g. a glass
and a cup) interfere with one another in proportion to their similarity,
representations of the distinct states of the same object interfere in
proportion to their dissimilarity. This interference, or competition, manifests
in a part of the brain that has been implicated in resolving competition.
Furthermore, activity in this area is predicted by the dissimilarity, elsewhere
in the brain, between sensorimotor instantiations of the described objects
distinct states. I shall end with new data (still too hot to touch) whose
interpretation is a first step towards a brain mechanism for distinguishing
between object types, tokens, and token-states. [Prior knowledge of the brain
is neither presumed, required, nor advantageous].
April
30 Simona Ghetti (Psychology, UC Davis).
Title:
Remembering during childhood
Abstract: The capacity to remember the past in vivid detail develops
considerably during childhood and emerges from the contribution of several
psychological processes. I will highlight the contribution of two classes of
these, relational binding processes and metacognitive processes. Relational
binding processes support the integration of the various features of an event
(e.g., what, when, where) into a memory representation that captures the
most important aspects of an experience. Metacognitive processes confer the
ability to reflect on memory quality, which might support decision making
(e.g., decisions to act on the basis of the content of ones memory).
Behavioral and neuroimaging evidence will be discussed.