1. The Mouse Was Chased by the Hat:
The Influence of Semantic Context on Phonetic Processing
Cristen Sullivan
Department of Psychology, Salem State University
The purpose of this experiment is to serve as a
behavioral pilot study exploring the connection between
semantic context and phonetic processing. Using a phonetic
morphing algorithm we created pairs of phonetically
ambiguous words, which have two possible interpretations.
Participants listened to sentences that were biased towards a
particular target word. (ex.. Her piano was never in TUNE
vs. He climbs the DUNE). After hearing the sentence
participants reported weather or not they heard a particular
consonant (T vs D) in the sentence they just heard. This
research posits that semantic context creates a bias towards
context appropriate solutions when subjects interpret
ambiguous stimuli in constraining compared to non
constrained conditions.
Abstract
Semantic Influences on Speech
Perception
Conclusions
Prospective Scanning Experiment
References
Subjects
Stimuli Task
Results
Borsky, S,Tuller, B, & Sharpio, L.P.(1998) “How to milk a coat:”The effects of semantic and
acoustic information on phoneme categorization. Journal of Acoustic Society of America,
103(5),2670-2676.
Gow,D.W.(2012)The cortical organization of lexical knowledge: A dual lexicon model of
spoken language processing.Brain and Language, 121, 273-288.
Gow,D.W, & Caplan, D.N. (2012) New levels of language processing complexity and
organization revealed by granger causation. Frontiers In Psychology. 506, 1-11.
Warren,R,& Warren R. Auditory Illusions and Confusions. Scientific American,223, 30-36.
This work was supported by NICDC grant R013108 (PI David Gow) through a subcontract to
Salem State University. My sincere thanks to Prof. Gow and A. Conrad Nied for their
assistance with this work.
• This study was approved by Institutional Review Boards at Salem State University, Massachusetts General Hospital, and MIT.
• 25 participants were used 4 male and 21 female. All participants were native speakers with no uncorrected auditory or visual
defects. • Task effects: more distractors eliminate participant
memorization and predictability of the experiment.
• A clear effect was needed to justify running the
prospective scanning experiment.
• Stimuli can be made stronger by eliminating the K target.
• The behavioral pilot test was conducted to determine
that our test produces the most robust result.
• Granger causation MEG and EEG scanning.
• Allows for causal interactions between brain regions
to be analyzed.• Does sentence context influence speech perception?
• Warren and Warren (1970) observed that people tend to
utilize sentence context to interpret ambiguous speech.
• Borsky (1997) , using goat or coat as target stimulus finds
participants are more likely to identify target words placed
in contextually biased sentences. However only a small
effect was noted.
• Top down and bottom up effects.
• This experiment seeks to create a more robust effect towards
context biased stimuli and serves as a behavioral pilot test
for a prospective brain scanning experiment.
Figure 2 from Borsky et al.
(1998) JASA
0
10
20
30
40
50
60
70
80
90
100
Voiceless Voiced
%Responses
Sentential/Semantic Bias
Consistent
Inconsistent
Our results based on 25 subjects
(Overall accuracy 93% on fillers)
Voiced “Dip” Unvoiced “Tip”
Time
Visual fixation stimulus (500ms)
Auditory stimulus
300ms delay
Visual probe
Stimulus with VOT cutback
Bad Items
12 t You can come here by TRAIN
21 t She joined a brownie TROOP sound?
57 d She says her horoscope is DIRE sound
68 d The jungle growth was quite DENSE
101 p Eat after the drinks are POURED
116 p The man losing his job PLED awkward
178 b He never paid his electric BILL
201 k The officer searched for a CLUE
202 k The door is about to CLOSE
203 k Winter in Massachusetts is very COLD
204 k You should invite her to COME
205 k Needlepoint is my favorite new CRAFT
206 k The raft floated down the CREEK sound
207 k The pirate ship needs a CREW sound?
208 k The bird was probably a CROW sound?
209 k The little prince was just CROWNED
210 k Her hair has a natural CURL
211 k He slice dthe apple to its CORE
212 k There are 30 students in the CLASS
213 k Our state fish is the COD
214 k Fall evenings are very COOL
215 k I would do it if I COULD
216 k They lift the beams by CRANE
219 k The mad man was totally CRAZED
220 k He bent down into a CROUCH
263 g Neptune was the Roman sea GOD sound
Top down effects Bottom up effects
Sound
Sound
Decision
Time (s)
0 1.156
-0.1398
0.1867
0
Time (s)
0 0.234
-0.09195
0.09637
0
Time (s)
0 1.294
-0.1313
0.1788
0
Time (s)
0 0.2758
-0.1208
0.1788
0
VOT=61msVOT=17ms
Time (s)
0 0.2466
-0.1208
0.1788
0
VOT=28ms
Voiced “Dip” (BDG) Unvoiced “Tip” (PTK)
• A large number of stimuli were
used.
• 150 word pairs with 350 distractor
stimuli.
• No nonsense words or continuously
repeated stimuli.
• Prevents memorization as well as
participant confusion.
• Participants stay more task focused.
MeaningMeaning
Sound