writt smm09 poster #180
TRANSCRIPT
Directional Electrode
EQUIPMENT
in the Atlantic Bottlenose Dolphin (Tursiops truncatus ):
TIME (ms)
∞ “Ring-Cap & Tail” with 5 active
10 mm Ag/AgCl electrodes
∞ Synergy NPE5 amplifier & software
∞ Lubell EV-UW30 underwater
speaker
∞ Cetacean Research Tech SQ26-MT
hydrophone
∞ Device to hold speaker and
hydrophone in correct position
(1) Department of Psychology, University of Kansas, 1415 Jayhawk Blvd., Lawrence, KS, 66045-7556, USA; (2) Marine Mammal Behavior & Cognition Lab, University of Southern Mississippi, 118 College Dr #5025, Hattiesburg, MS, 39406-5025, USA; (3) ISPA, Rua Jardim do Tabaco 34, Lisboa, 1149-
041, Portugal; (4) Projecto Delfim, Centro Português de Estudo dos Mamíferos Marinhos, Rua Alto do Duque 45, Lisboa, 1400-009 , Portugal; (5) Communication Sciences & Disorders, University of Cincinnati Medical Center, 345A French East, 3202 Eden Ave, Cincinnati, OH, 45267-0379, USA
Dominie Madonna Writt (1,2), Patrícia Rachinas Lopes (3,4), Stan A. Kuczaj (2), Manuel E. dos Santos (3,4), Peter M. Scheifele (5)
Identification of Endogenous Event-Related Potentials
Applications for Communication Research
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Topography o f
component peaks
reflects interactions
between multiple
possible generator
sources and the
dipole dispersion
across various tissue
types.
Distance
above or
below the
baseline, or
between the
peak & the
trough . Can
reflect sum
resources.
Time
between
stimulus
presentation
& waveform
peak or onset.
Can reflect
processing
time.
NEURAL PROCESSING LEVELS
Exogenous ∞ Shorter Latency Components (<100-200 ms)
∞ Automatic Stimulus-Evoked Processes
∞ Valuable for Sensory System Research
∞ Relatively Well Established in Marine Mammals
Endogenous ∞ Longer Latency (>100-200 ms)
∞ Decision-Related Processes
∞ Useful for Information Processing Research
∞ Not yet established in Marine Mammals
METHODS RESULTS & DISCUSSION
“Ring-Cap”
Similar to method
used in human
multi-channel
ERP Research
Traditional Recording Method for Odontocetes
New Method:
Change Detection &
Information Processing
“The Classic P300”
(Properties for Human Adults)
∞ Positive central-parietal maximal waveform
∞ Peaks ~300+ ms following stimulus onset
∞ Amplitude inversely proportional to stimulus probability
∞ All properties influenced by stimulus value & complexity,
likely reflecting “Context-Updating” processes.
P300-like component recorded from Tursiops truncatus by
Woods, Ridgway, Carder, & Bullock (1986) using extracranial
electrodes over the skull, near the primary auditory cortices of
the suprasylvain gyrus (SSG).
COMMUNICATION: Further studies of these components could assist in the isolation and identification of marine mammal communication signals.
Odontocetes’ divergent & unique evolution may produce differences in neural processes between our species, but
convergent social behaviors may also have resulted in some unexpected similarities. This method could offer
insights into these phenomena.
N1-P2 Reflects simple stimulus detection
ERP
vent elated otentials
BACKGROUND
Placement System (suggested standardization for odontocetes)
Apollo (5 yrs)
Lotus (13 yrs)
Hugo (12 yrs)
SUBJECTS Gender: Male
Expand methods to investigate communication systems when overt behavioral responses are difficult to:
Can be combined with behavioral measures or reflect processes independent from overt behavior.
STIMULUS PRESENTATION:
“The Oddball Paradigm”
Tones (2, 4, 6, or 8 kHz*) 100 ms 85%-Standard 15%-Oddball
Silence as Oddball
2-4 Minute Random Blocks
1000 ms trace recordings
~50-traces/dolphin of each oddball assigned in random blocks over 3 wks.
*Tone frequencies were limited by stimulus
generating equipment. Data analysis of the
higher frequencies & complex stimuli pending.
Recording Parameters:
Band-Pass Filtered: 0.06-50 Hz
Artifact Rejection at 80 µV
(Only included averages >20% retention rate)
1-2 sec. random ISI
Video Behavior Monitoring before, during, & after program participation,
to assess any related behavioral responses, in the interest of dolphin
welfare. No negative response observed–pending analysis.
• Generate
• Interpret
• Time • Training
The Value of ERP for
Marine Mammal Communication Research
QUESTION
• Is there a reliable P300 like component in dolphins that is related to stimulus probability & found in the
processing latencies that could be sensitive to signal information value &
complexity?
• Based on previous research in humans, dolphins, and chimpanzees,
we expect such component to be identified within the 300-700 ms
latency range.
B. The 480-660 ms posterior positive component with a longer latency for the rare-tone condition, suggests -
that could be sensitive to processing complexity, relevant to future studies of communication.
Lines show significant
mean differences (p< .05)
FUTURE APPLICATIONS
A. The 120-260 ms component that differs in polarity & location by condition, suggests that the posterior negativity is specific to the processing of acoustic stimuli.
ALL CONDITIONS BOLD – Oddball (15%)
THIN- Standard (85%)
Comparison of Tone & No Tone (outlined)
Conditions
C. 720-760 ms anterior-maximal positive component only in the rare tone conditions, suggests a distinct component that reflects the integration of information provided by the deviant stimulus.
LOCATION (by Human 10-20 System)
Acknowledgments: Many thanks are due to Élio Vicente, Marco Braganca, and all the trainers and staff at Zoomarine (Algarve, Portugal) for their support and tireless efforts. Without their dedication, this project would not have been possible. Additional financial support provided by a KU honors fellowship to the first author and through U.S.
and Kansas State agencies. Thanks also to Joana Augusto for her invaluable support in stimulus recording, as well as equipment design, setup, and testing. Thanks to Jim Juola , Patricia Hawley, Andrea Greenhoot, Allard Jongman , and Michael Greenfield for their encouragement and advice in designing the project.
Please, feel free to contact to the first author at [email protected] with any comments, questions, or suggestions; also, if you are interested in discussing the potential application of ERP to your research programs.
TONE NO TONE
latency (ms) - 20 ms time windows) 100-300 300-700 100-300 300-700
subject
time X X
time * channel X X X
time * channel * probability X X
probability X X X
channel X
channel * probability X
100 160
760
560 620
OMNIBUS REPEATED-MEASURES ANOVA time (10 or 20) x channel (5) x probability (2) x subject (3)
1.5 sec. ISI
A
B
C
AM
PL
ITU
DE
(u
V)-
odd
ball-
sta
nd
ard
diffe
rences g
iven
-2.5
2.3
1.9
2.5
5.2
3.4
A1R3 -
A1L3 –
P2 - Tone
P2 -
P2 – Tone
A1L3 – Tone
A1L3 –
Oddball
Standard
If eye-to-naris (EN)
distance is 25 cm,
then 1 Placement
Unit is 2.5 cm
(10% EN).
SSG The current findings are important for establishing ERP components for use in answering
future, more complex research questions.
Table of Significant Mean Differences between Oddball
(15%) & Standard (85%) Component Amplitudes (µV)
Table of Significant Mean Differences between Oddball
(15%) & Standard (85%) Component Amplitudes (µV)