S1 (FriAM 1-65) - The Psychonomic Society

Friday Morning Papers 49–54
congruence) and name (name-congruence) of keys on a keyboard were
dissociated. In two experiments participants responded with crossed
hands to the color of colored letters on a keyboard. In Experiment 1
the keys were without names; in Experiment 2 the keys were renamed.
This resulted in effector-congruent, incongruent, and different name-/
key-congruent conditions. An effect of effector-congruence was always
found. In Experiment 1 participants showed facilitation in the
key-congruent/name-neutral condition. In Experiment 2 participants
showed interference in the key-congruent/name-incongruent condition.
No effect was obtained in the key-incongruent/name-congruent
condition. Thus, key names are neither sufficient nor necessary for the
activation of spatial representations in skilled typing. However, key
names are processed, and if they do not match the keys they disturb
the development of spatial representations.
10:40–10:55 (49)
Disruption of Timing by Delayed Auditory Feedback As a Function
of Movement Kinematics. PETER Q. PFORDRESHER & XIAOJUN
SHAN, University at Buffalo—It is well known that timing of rhythm
production is disrupted by delayed auditory feedback (DAF), and that
disruption varies with delay amount. We tested the hypothesis that disruption
depends on the state of the movement trajectory at the onset
of DAF. Participants tapped isochronous rhythms at a rate specified
by a metronome while hearing DAF of differing amounts. Threedimensional
motion capture was used to analyze movement trajectories.
Intertap intervals (ITIs) varied as an approximately sinusoidal
function of feedback condition; they were longest for shorter delays
(�50% of ITIs) and sped up for longer delays (�50%). Finger velocity,
but not position, predicted change to ITIs: timing slowed when
DAF coincided with positive velocities (upward swing) and sped up
when DAF coincided with negative velocities. Thus, DAF’s effect on
timing may not constitute “disruption” per se, but may instead reflect
associations between perceived stimulus onsets and phases within
movement trajectories.
11:00–11:15 (50)
Anticipatory Finger Movements in Musical Sequences. CAROLINE
PALMER & WERNER GOEBL, McGill University—Rapid sequential
tasks such as music performance require that finger motion trajectories
be computed and executed during the production of other motion
trajectories, conditions which often reflect coarticulation. We investigated
the anticipatory movements of pianists’ fingers toward piano
keys in performances at different tempi, while manipulating the sequential
distance between repetitions of specific finger movements.
Skilled pianists performed melodies from memory in a synchronizationcontinuation
task at four different fast rates while a passive motion
capture system recorded the pianists’ fingers and piano keys. Anticipatory
movements of a finger toward its next keypress began later in
absolute time but sooner in relative time (number of sequence events)
at faster rates than at slower rates. Furthermore, these anticipatory
movements were larger and sooner for less coupled fingers, indicating
that coarticulatory properties of sequential finger movements constrain
anticipatory motion in timed sequential tasks.
11:20–11:35 (51)
Tremor As a Bridge: The Continuous Flow of Information From
Intention to Action. RAJAL G. COHEN & DAVID A. ROSENBAUM,
Pennsylvania State University (read by David A. Rosenbaum)—The
question of how intentions are translated into actions has been addressed
with a variety of approaches, ranging from philosophy to neurophysiology.
Here, we asked a new question about such translation,
using a measure based in cognitive neuroscience. The question was
whether intentions are translated into actions discretely, in a stagewise
fashion, or continuously, in a cascade? Our approach to this question
was inspired by the observation that microsaccades, the tiny eye
movements that arise during visual fixation, are more likely to occur
in the direction of forthcoming movement than in the opposite direction.
We asked whether a similar phenomenon applies to physiologi-
8
cal tremor of the upper extremity. Consistent with the continuous
translation hypothesis, we found that when people pause before moving,
the small movements inherent in their pauses are biased along the
axes of forthcoming voluntary movement. This outcome suggests that
tremor offers a new window into mental function.
11:40–11:55 (52)
Mirror Neurons in Humans? MORTON ANN GERNSBACHER,
JENNIFER L. STEVENSON, & EMILY K. SCHWEIGERT, University
of Wisconsin, Madison—Mirror neurons were so named after Rizzolatti
and colleagues’ serendipitous discovery during single-cell recording in
macaques: A set of neurons in ventrolateral premotor cortex fired both
when the monkey spontaneously executed an action, such as reaching
for a pellet, and when the monkey spontaneously observed a conspecific
executing the same action. We searched the 269 articles indexed
through the year 2006 on PubMed and Psych Abstracts with the terms
“mirror neuron/s” and “mirror neuron system.” We discovered that no
human neuroimaging study had actually replicated this effect, including
Rizzolatti and colleagues’ (1995/1996) human PET experiments,
from which Rizzolatti cautioned that “brain imaging experiments carried
out in humans have failed up to now to convincingly demonstrate
the existence of a cortical circuit similar to that described in the monkey,”
but which are nonetheless cited by the vast majority of articles
claiming that mirror neurons have been observed in humans.
Recognition Processes
Seaview, Friday Morning, 9:40–12:00
Chaired by William E. Hockley, Wilfrid Laurier University
9:40–9:55 (53)
Opposing Strength-Based Mirror Effects for Words Versus Pictures:
Evidence for Within-List Criterion Changes. WILLIAM E.
HOCKLEY, Wilfrid Laurier University—Strength-based mirror effects
are seen when the hit rate is higher and the false alarm rate is
lower following strongly encoded study lists compared to more
weakly encoded lists. Hockley and Niewiamdomski (in press) demonstrated
opposing mirror effects for item and associative recognition by
differentially varying the presentation rate of items and pairs within
lists. They interpreted these results as indicating that participants
adopted different decision criteria for item and associative recognition
tests. In the present experiments separate and opposing mirror effects
were found by manipulating the presentation rate of words and pictures
(line drawings) between and within lists. If strength-based mirror
effects occur because participants use a more conservative decision
criterion for strong compared to weak lists, then the present
results demonstrate that participants can adopt different decision criteria
for words and pictures and alternate between these criteria on a
trial-by-trial basis during the course of the recognition test.
10:00–10:15 (54)
Is Familiarity-Based or Recollection-Based Recognition Faster: The
Source of the Contradicting Findings. JERWEN JOU, University of
Texas, Pan American—Response-signal paradigm experiments showed
that recognition decisions made under earlier response deadlines are
familiarity-based whereas those made under later deadlines are
recollection-based. This supports the idea that recollection-based
recognitions take longer than familiarity-based recognitions. In contrast,
Remember–Know paradigm experiments showed that
Remember-responses (recollection-based) are faster than Knowresponses
(familiarity-based). Is there a coherent explanation for these
two contradictory findings? It is suggested that the two experimental
paradigms measure two different dimensions of a recognition process.
That is, the response-signal experiments measure the difficulty levels
of a recognition (e.g., easier global recognitions take place earlier than
detailed recognitions), whereas the Remember–Know paradigm measures
the strength of memory. In this study, difficulty levels of recognition
and degrees of learning were independently manipulated. The