language and motion perception final
TRANSCRIPT
On the road to somewhere:
Brain potentials reflect language effects on motion event perception
Presented by Katie Steck
Flecken, Athanasopoulos, Kuipers, & Thierry 2015
Background Information
‘‘Users of markedly different grammars are pointed by their grammars toward different types of observations and different evaluations of externally similar
acts of observation’’ -Whorf, 1940/1956
Language Matters in Brain PotentialsThierry et al. (2009):
- Greek “ghalazio” and “ble” - light and dark blue- Greek speakers greater and faster perceptual discrimination between light blue and dark blue
Boutonnet et al. (2013):- English “cup” and “mug” v. Spanish “taza”- English speakers greater deviant-related negativity brain potentials than Spanish speakers
Using brain potentials, can you see similar language effects for motion?
How would language affect motion perception?
Grammatical Aspect- Grammatical category that expresses
how an action, event, or state (denoted by a verb), relates to the flow of time
-Perfective - bounded, no time inference- “I helped him”
-Imperfective - progressive (continuous, to be verb + _ing)
- “I was helping him”
Verb Form Influence
Anderson, Matlock, Fausey, and Spivey (2008):- Gave sentences either contain perfective or
imperfective past verb form.- Using a computer mouse, participants placed
character into a scene to match the description
Perfective Dropped character toward destination
Imperfective Dropped character at an intermediate point
Aspect and Non-Aspect languages
Aspect (English, Arabic, Russian, Spanish): Tend not to mention endpoints when not the
focus of the sentence.
- “A woman is walking” (perhaps towards something, but it doesn’t really matter what)
Non-aspect (Afrikaans, German, Swedish): Linguistic bias towards action goals and
motion event endpoints and dependent on perspective of viewer
- “A woman walks towards a building”
Language FocusLangacker (1987, 2008); Radden & Dirven, (2007):
Gave a scene where a person is walking along a road, with a house at a distance, but the clip ends before the person has gone anywhere near the house
-Describe this event“A person is walking”“A person walks to a house”
Focus on endpoint or the ongoing phase of event?
Aspect languages focus on processNon-Aspect languages focus on endpoint
Verbal interference can change results
Using brain potentials, can you see similar language effects for motion?
Experiment 1- Methods
Participants:20 English speakers (UK)20 German speakers (Netherlands)
Process:Animation first (1000 ms)Blank screen (200 ms)Target picture (600 ms)Blank screen between trials (800 ms)
Press a button if the picture exactly matches the preceding animation
Experiment 1 - Methods
492 Total Trials5% of animation-picture pairs full match (24 trials)
75% Full mismatch (372 trials)10% Endpoint match (48)
10% Trajectory match (48)
Hypotheses- Experiment 1
1. German speakers- Larger P3 in endpoint match than trajectory match
2. English speakers - Similar P3 in both endpoint and trajectory matches
3. Larger P3 amplitudes for full match conditions (both groups)
Experiment 1- Results
English - Peak at 520 msGerman- Peak at 610 ms
No significant difference in correct button pushes (90%)
Experiment 1 - Initial RM ANOVA Main Effects
Endpoint Match
Complete Mismatch
Po
siti
ve P
3 a
mp
litu
de
Full Match
Trajectory Match
p < .05 p < .05
p < .05 p < .05p < .001
p =n.s.
English and German groups similar pattern:
Groups were both attentive and motivated
Experiment 1- German Group
Higher P3 for Full Match than all others (p < .001)
Higher P3 for Endpoint Match than Mismatch (p <.05)
NS P3 difference for Trajectory Match and Mismatch (p <.05)
**Higher P3 for Endpoint Match than Trajectory Match (p <.05)**
Experiment 1- English Group
Higher P3 for Full Match than all others (p < .001)
Higher P3 for both Endpoint and Trajectory Match than Mismatch (p <.05)
**NS P3 for Endpoint Match than Trajectory Match (p =.073)**
Experiment 1- Interaction
Experiment 1- Results Summary
Groups were both attentive and motivated
German larger overall peak and slope, possibly explained by German group slower to reject partial matches
When there was significance, it was for more focus on the endpoint
- German group it lasted longer and differences between the mismatch condition only in the endpoint match condition, pointing to language differences in perceptual processing
Experiment 2- MethodsParticipants:15 English Speakers19 German Speakers
Process:Picture first (600 ms)Blank Screen (200 ms)Animation (1000 ms)Between trial (800ms)
- Match? Press “Yes” or “No” buttons, Response time and accuracy recorded
Fully randomizedEach picture (4) preceded by each animation (4) = 16 combosRepeated 10 times = 160 trialsAll together, 40 trials each of full match, mismatch, endpoint match, trajectory match
600 800
Experiment 2- Accuracy Results
No interactionNo main effect for groupMain effect of condition:
Did better correctly identifying mismatch than full matchNo difference between mismatch and endpointSlight difference between mismatch and trajectoryNo difference between endpoint and trajectory
Experiment 2- Reaction Time Results
No interactionNo main effect for groupMain effect of condition:
Reaction times fastest for mismatch trialsNo differences between critical conditions
Experiment 2- Correct “No” Button Results
No main effect for groupMain effect of condition:
Faster “no’s” for full mismatch than partial mismatchSignificant Interaction
German reaction times for partial mismatches slower than their reaction times for complete mismatchN.S. in English group
Experiment 2- Incorrect “Yes” Button Results
No interactionNon significant trend for group main effectMain effect of condition:
Accidentally pushed yes more often on partial matches than full mismatches
Experiment 2- Results SummaryGroups perform roughly the same in accuracy rates and speed of processing
Performance fastest and most accurate on full mismatch condition
Worse for both groups on the trajectory match condition (Language-independent bias for endpoints in motion (Slobin, 2006; Zacks & Tversky, 2001))
German reaction times slower for the partial mismatch than full mismatch (helps explain P3)
*Picture and motion pairing a non-verbal task*- Online verbal encoding strategies not likely*
The Point
German group had greater attention devoted to endpoints
English group had more equal attention devoted to endpoint and trajectory
Automatic processing for motion perception varies based on how you have experience coding things in your language
Limitations and Future Studies
Possibility of shape labeling-Correct in future research
Experiment 1 and 2 different people
Small sample size
Additional future research-Real world motion events
Fin
Extras
-Task processing and attention devoted to execution of task similar in Germans and English
-English P3 peak slighly earlier and shorter, less positive than German
-English and German similar in speed for detecting a full match
-Germans slower at rejecting partial matches
Extras
-Germans have a more positive P3 wave for endpoint match than trajectory match
- Endpoint processed with more attention and perceived as more relevant or salient than trajectory when matching animations with pictures
-English no sustained differences in P3 wave for endpoint match vs trajectory match
- No attentional bias, both elements similarly attended to