Second PhD Students’ Workshop

Second PhD Students’ Workshop
International Research Training Group (IRTG)
“Adaptive Minds: Neural and Environmental
Constraints on Learning and Memory”
July 16-18, 2010, Hofgut Imsbach, Theley
http://www.hofgut-imsbach.eu
Second PhD Students’ Workshop, Theley
Partner Institutions of the IRTG “Adaptive Minds”:
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Departments of Psychology and Neuroradiology, Saarland University,
Saarbrücken, Germany (http://www.adaptiveminds.de)
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Institute of Psychology, Chinese Academy of Sciences (IP-CAS;
http://english.psych.cas.cn/)
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Contents
Page
1. Programme
4
2. Important information on the workshop
6
3. Abstracts of the PhD students
Anna Marie Arend
7
Regine Bader
8
Nicole Brunnemann
9
Teresa M. Halsband
10
Mareike Kardinal
11
Olga Kukina
12
Susanne Lehner
13
Heinrich R. Liesefeld
14
Kalina Petrova
15
Melanie Schmitz
16
Julia A. Schneiders
17
Volker Sprondel
18
Katja Umla-Runge
19
Kerstin Unger
20
Kathrin S. Utz
21
Lamei Wang
22
Heike S. Weber
23
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1. Programme
Friday, July 16
Until 15:00
Arrival (important: check-in is usually not possible before 15:00, so please check-in
later, e.g., after the talks on Friday)
15:00-15:50
Kerstin Unger: It's worse than expected, but it doesn't matter – Relating cognitive
and affective-motivational theories of performance monitoring
15:50-16:40
Teresa Halsband: The influence of reward-motivated learning on memory retrieval:
An ERP approach
16:40-17:00
Coffee break “De Luxe”
17:00-17:50
Melanie Schmitz: The representation and activation of evaluative connotations
17:50-18:40
Kalina Petrova: Attentional capture by biologically relevant stimuli
19:00
Dinner
20:00-21:00
Meeting of the principal investigators
Saturday, July 17
8:30-9:20
Kathrin Utz: Spatial-perceptive disorders and spatial neglect: Neuroanatomy, clinical
findings and vestibular modulation
9:20-10:10
Mareike Kardinal: Modulation of spatial-temporal associations in healthy individuals
and neglect patients
10:10-10:40
Coffee break “De Luxe”
10:40-11:30
Susanne Lehner: Developmental transitions and cross-cultural implications in shortterm memory strategies
11:30-12:20
Lamei Wang: Cross-cultural action acquisition and representation in children
12:20-14:00
Lunch
14:00-14:50
Regine Bader: Differences between pre-experimentally and experimentally unitized
word pairs – Semantic integration in episodic memory
14:50-15:40
Anna Arend: Plasticity of selection mechanisms in visual working memory
15:40
Coffee break “ECO”
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Thereafter
Leisure activities as suggested by the doctoral students:
1. Good weather: Hiking
2. Bad weather: Parlor games (e.g., “Werwölfe”, “Activity) 1
19:00
Dinner
20:00-22:00
Plenary session about general topics concerning the IRTG
(including, e.g., invitation of guest researchers, topics for workshops, publication
strategies, career development, evaluation of doctoral theses, etc.;
Further topics as suggested by the doctoral students: comparison of academic career
in Germany and Anglo-Saxon countries, tips for applying for jobs in science in [AngloSaxon] countries)
Further entertainment as to be proposed by the doctoral students
Sunday, July 18
Important:
Please check-out rooms before 12:00
8:30-9:20
Volker Sprondel: The role of strategic processing for the development of episodic
memory retrieval
9:20-10:10
Nicole Brunnemann: Cognitive development in preterm children: Selective deficits in
declarative memory
10:10-10:30
Coffee break “ECO”
10:30-11:20
René Liesefeld: Decomposing mental rotation
11:20-12:10
Katja Umla-Runge: Hierarchically organized action representations in memory –
Effects of motor similarity and familiarity on means and ends representations
12:10-13:30
Lunch
13:30
Departure
1
Games/materials will be brought by the doctoral students.
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2. Important information on the workshop
Travel
− The address of the Hotel is Hofgut Imsbach, Primstalstraße, 66636 Tholey / Theley, Tel.:
06853 50 14 – 0.
− From the University Campus, the travel to the Hofgut Imsbach takes ca. 45 minutes (47
km) by car.
− Participants who will take their car (preferably with 2-3 further passengers) or travel by
bus/train to the Hofgut Imsbach are asked to hand in a Dienstreiseantrag to the coordinator of the IRTG before July 14th so that the travel costs can be reimbursed.
− Further information on the travel to the Hofgut Imsbach can be found here:
http://www.hofgut-imsbach.eu/content/view/15/22/lang,german/.
Talks
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Aim of the talks: to give an overview of the doctoral project, including research questions, what has been done and found so far, and what is left to be done during the remaining time of the doctoral project.
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Duration of the talks: 30 min talk (maximum) plus 20 min discussion.
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Talks will be given in English.
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Please include a final slide on the time schedule / road map about what has to be done
during the remaining time of the doctoral project and what the further “milestones” are.
Abstracts
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All doctoral students (including those who are in China at the moment) are asked to send
an abstract of not more than 300 words (title included) to the coordinator of the IRTG
until June 30th, 2010.
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The abstracts are not supposed to summarize the talks that will be given during the
workshop. Rather, they are instead intended to provide a general overview / synopsis of
the doctoral project, including the research questions, the main empirical findings, and
the aims and topics of the experiments that are in preparation.
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The abstracts should be written in English. They are suggested to only involve the names
of the doctoral students as authors of the abstracts.
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The abstracts are printed in a booklet of the workshop that provides general information
about the projects of all doctoral students of the IRTG.
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3. Abstracts of the PhD students
Plasticity of selection mechanisms in visual working memory
Anna Marie Arend
Cognitive Psychology Unit, Saarland University
Visual working memory (vWM) provides a temporary mental representation of visual information. In the retention phase of a change detection task, slow potentials (SPs) and contralateral delay activity (CDA) – the amplitude difference between the contra- and the ipsilateral SPs – are observed over posterior brain areas and they are considered as electrophysiological correlates of item memory. Their amplitudes increase with the number of represented
items and they are related to the individual memory capacity as well as the ability to filter
out distractors. We investigated whether this ability could be increased and this change is
reflected in the electrophysiological correlates.
In Experiment 1 we realized an incentive-manipulation. Participants behaviorally improved
capacity under incentives. Both components showed modulations as a function of vWM-load
but only SPs were sensitive to the incentive-manipulation.
Experiment 2 aimed at investigating whether also information in the to-be-ignored visual
hemifield influences CDA and SP. We orthogonally varied the number of items in the relevant and irrelevant hemifield. CDA was a function of only the relevant items, whereas SPs
were influenced also by irrelevant items if only one item was to remember. We conclude
that SPs correlate to the number of represented items and that distractors are not inhibited
when capacity is left over.
In a training study we analyzed the plasticity of selection mechanism in vWM. Participants
trained to filter distractors in a multiple object tracking task. Despite of training-effects in
filter efficiency, we found no transfer to the filter efficiency in the change detection task.
These results indicate that spatial filtering is not a unique process.
By means of fMRI we plan to localize brain areas whose activation covaries to the number of
items that are remembered and the number of distractors that are filtered out.
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Differences between pre-experimentally and experimentally unitized word pairs –
Semantic integration in episodic memory
Regine Bader
Dept. of Neuroradiology / Experimental Neuropsychology Unit, Saarland University
Remembering past events depends critically on the memory for arbitrary associations which
was generally assumed to require recollection. However, recent research has shown that
familiarity supports associative memory if associations are unitized, i.e. integrated into a
single configuration. Importantly, two items can be pre-experimentally unitized, e.g. two
words of a compound (NIGHT CLUB), or they can be unitized during encoding, e.g. by combining the words to a novel concept (BEACH STAIRS = Steps directly leading to the bay). Until
now, the two types of unitizations have not been directly compared within one study. Using
functional neuroimaging, we expect to find differences being not evident on a behavioral
level. According to the discrepancy-attribution-hypothesis, we propose that the unexpected
enhancement of conceptual fluency for previously unrelated, experimentally unitized pairs is
attributed to a prior occurrence (conceptually-driven familiarity). Contrastingly, preexperimentally unitized pairs are assumed to be recognized by strengthening of the preexisting representation (experimental familiarity). Investigating ERP retrieval correlates in a
recognition task, experimental familiarity is expected to elicit a mid-frontal old/new effect
whereas conceptually-driven familiarity is assumed to be accompanied by a parietally distributed old/new effect in the same time interval. As conceptually-driven familiarity is expected to be independent of episodic retrieval intention and adhering to an automatic
process of semantic integration, an indirect memory test is planned to compare the early
parietal old/new effect to the generic N400 effect. An fMRI study will investigate the brain
structures involved in recognition of the two kinds of unitizations relating respective ERP and
fMRI findings for the first time. An important common role of perirhinal cortex was proposed, but we postulate a specific role for the left inferior frontal gyrus for experimental
unitization, an area previously related to semantic integration.
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Cognitive development in preterm children: Selective deficits in declarative memory
Nicole Brunnemann
Experimental Neuropsychology Unit, Saarland University
The development of cognitive functions in children born preterm is rarely examined. Evidence from behavioral studies suggests that preterms, compared to full-terms, are at increased risk for cognitive impairments. However, it is unclear whether prematurity has an
impact on cognition in general or whether specific functions are affected. To shed light on
this issue, declarative memory (including recognition memory: familiarity and recollection)
and attentional processes were explored in 8-10-year-old preterms and full-terms by means
of neuropsychological tests and event-related potentials (ERPs). Additionally, for the purpose of comparability, ERPs of an adult control group were recorded. By using ERPs this
study provides important insights into the functional development of the brain in preterms.
In the neuropsychological tests, preterms compared to full-terms had lower scores in semantic memory, but not in episodic and working memory tasks, even if controlled for intelligence and socioeconomic status. Regarding attention, an oddball task revealed similar target- and novelty-processing in all groups, suggesting that attentional processes are not impaired in preterms. The findings in the recognition task showed that under conditions were
participants are forced to make old/new decisions quickly and, in turn, recollection is hindered, all groups show the ERP correlate of familiarity. However, in a nonspeeded condition
preterms, in contrast to full-terms and adults did not show an ERP correlate of recollection,
even after controlling for working memory performance and socioeconomic status. Furthermore, in preterms, a positive correlation between gestational age and the magnitude of
the ERP correlate of recollection was found. Alternative interpretations (e.g. a task-resource
artefact) are currently under investigation. To determine whether reduced recollective
processing in preterms is associated with structural brain abnormalities (e.g. reduced hippocampal volumes), in a next step, structural magnetic resonance images will be analysed. Preliminary, the findings suggest an association between prematurity and reduced recollective
processing.
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The influence of reward-motivated learning on memory retrieval: An ERP approach
Teresa M. Halsband
Experimental Neuropsychology Unit, Saarland University
Reward anticipation during learning was shown to support memory formation by direct neuronal connections between the mesolimbic dopamine system and the medial temporal lobe
memory system. For successful retrieval of previously learned materials, flexible adaptation
to the task demands, i.e. the adaptation of a retrieval orientation is needed. Event-related
potentials (ERPs) to correctly rejected new items in recognition memory tests differ according to the sought-for information in memory, and can therefore be taken as a neural correlate of retrieval orientation. So far, it is largely unknown by which mechanisms reward anticipation modulates encoding and retrieval processes. The main interest of this project is to
explore how retrieval orientations are modulated by reward anticipation and whether this
modulation results in more efficient memory retrieval of motivational information.
In a first experiment, we found the expected material-specific retrieval orientation effect, i.e.
more negative going ERPs to verbal cues when previously studied pictures are the sought-for
information instead of previously studied words. This effect presumably reflects the constraining of cue processing to semantic features. Additionally, despite equal memory performance in both reward conditions, the ERP contrast between items studied with high and
low reward cues revealed more positive-going ERPs in the high reward condition. This frontally distributed effect is interpreted as a reward-induced retrieval orientation effect, implying that reward motivation at learning can result in the adoption of a reward specific retrieval orientation in order to retrieve highly motivational information in an efficient way.
While in experiment 1 reward was indicated by an external cue, in experiment 2 reward indication was directly linked to the study task performance. We expect a higher degree of
involvement of the dopamine system resulting in clearer reward-induced retrieval orientation effects and better memory performance for items of the high versus low reward condition.
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Modulation of spatial-temporal associations in healthy individuals and neglect patients
Mareike Kardinal
Clinical Neuropsychology Unit, Saarland University
Recent research has indicated the involvement of spatial codes in the representation of
temporal intervals in the supra-second range (for a review see Oliveri et al., 2009a). Short
durations seem to be associated with the left side of mental space whereas long intervals
are linked to the right one. This phenomenon has been denominated as STARC effect and
suggests the existence of a horizontal mental time line (Vallesi et al., 2008; Isihara et al.,
2008).
Neuropsychological studies report that neglect patients who exhibit deficits in spatial
processing also demonstrate difficulties in time perception (Danckert et al., 2007; Oliveri et
al., 2009b). Other lines of research demonstrate that time processing can be modulated
through bottom-up processes, such as prism adaptation or optokinetic stimulation (Frassinetti et al., 2009; Vicario et al., 2007)
In my doctoral thesis I aim to investigate the extent to which spatial-temporal interactions
may be modulated in healthy individuals and neglect patients. A first object of research will
be to analyze if changes in the external spatial frame induced by trunk or head rotation lead
to altered time estimation. Previous work has shown that the rightward errors neglect patients typically demonstrate in line bisection can be reduced by turning the head or trunk to
the left (Schindler & Kerkhoff, 1997). Notably, physical line bisection biases correlate with
those exhibited for the bisection of representational (number) space (Zorzi, 2002).
Further studies of my thesis will include examining the effects of Galvanic-Vestibular Stimulation on time and number processing, which are thought to share common neuronal circuits
(Walsh, 2003). It is also planned to investigate cross-cultural differences in the representation of temporal information. Does the mental time line take on a vertical orientation in Chinese individuals as suggested by linguistic research (Boroditsky, 2001)?
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Universal or culture specific: Does semantic memory
differentially support associative recognition for Germans and Chinese?
Olga Kukina
Experimental Neuropsychology Unit, Saarland University
Semantic and episodic memory closely interact, such that the properties of underlying semantic representations to some extent determine whether familiarity or recollection is involved in episodic recognition.
In two experiments, using event-related potentials and a behavioral remember-know paradigm, we examine whether different types of semantic relations, i.e., categorical and thematic, differentially affect mechanisms involved in associative recognition for German participants. Results of both experiments suggest that for the successful recognition of categorical
associates, recollection is needed, while for retrieval of thematic relation familiarity alone is
enough. This outcome implies that properties of semantic links between the associates are
crucial for determining the mnemonic processes engaged at episodic memory retrieval.
An intriguing question is, however, whether the observed pattern of differential involvement
of familiarity/recollection in retrieval of categorical/thematic relations observed for German
participants is solely determined by the underlying properties of semantic representations
and can be generalized to other cultures.
Cross-cultural research on categorization showed that while Westerners prefer categorical
groupings (e.g., policeman-postman), East-Asians tend to form thematic ones (e.g., policeman-uniform), suggesting differential weighting of the categorical/thematic relations in the
semantic memory of Westerners/Asians.
It is, therefore, possible that the enhanced recollection observed for categorical pairs for
German participants was not due to a genuine difference in the properties of categorical and
thematic representations per se, but can rather be attributed to such a “bias” of German
participants towards categorical relations. If so, East Asian (Chinese) participants should
show an orthogonally different pattern of results on associative recognition test, in that recollection should be boosted for thematic compared to categorical pairs.
Two mirror experiments were recently conducted with Chinese participants to address the
issue. The obtained data is still a subject for analysis.
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Developmental transitions and cross-cultural implications in short-term memory strategies
Susanne Lehner
Developmental Psychology Unit, Saarland University
My dissertation aims to investigate: (1) strategy changes in children (5-, 7-, and 9-year-olds)
and young adults in visual short-term memory tasks and (2) strategy-efficiency across agegroups and cultures.
Recent studies point to changes from a visual strategy in short-term recall of visual stimuli,
to a mixed strategy, using visual as well as verbal codes, to a verbal recoding strategy (e.g.,
Palmer, 2000). Evidence mainly stems from comparing recall in visually-similar-object-lists
with similar-sounding-object-lists and “neutral” lists. Further research with different methods is in demand. Additionally, coloured pictures are faster verbalized than line drawings
(Rossion & Pourtois, 2004) and abstract pictures are frequently not verbalized even by adults
(e.g. Lüer et al., 1998). I investigate the role stimuli characteristics play in strategy use and
whether strategy changes are universal or differ between cultures (e.g. due to alphabetic vs.
logographic writing).
Naming stimuli during encoding can promote recall and verbal strategy use in younger children (e.g. Hitch et al., 1991). I am currently researching whether the efficiency of naming differs based on the strategies used as well as the to-be-remembered material. Furthermore
verbal strategies seem to be more frequently employed and more effective for Westerners
than Easterners (e.g. Kim 2002, 2008). It should be investigated whether this also holds true
for memory tasks and if there are cross-cultural differences in the efficiency of a visual strategy.
The present results provide (1) evidence by a new experimental approach for a strategy
change from visual to verbal strategies and show (2) that naming of black-and-white line
drawings enhances recall performance in younger but not older children. The consistency of
the results on strategy change across cultures and materials and the efficiency of a verbal vs.
visual strategy will be investigated in further studies.
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Decomposing mental rotation
Heinrich R. Liesefeld
Cognitive Psychology Unit, Saarland University
Mental rotation (MR) is a prototypical paradigm for exploring visual imagery/reasoning. It
can be considered a truly active visuo-spatial working memory (WM) task. However, few is
known about representations in MR and therefore about causes for differences between
individuals and stimuli.
In an initial study a task isolating the MR process by controlling participants' strategies was
developed. MR was measured online by means of the rotation-related EEG-negativity. We
showed that in addition to the amount also the direction of rotation influences the ease of
rotating alphanumeric characters. A currently conducted behavioral experiment aims to provide additional support.
In further behavioral studies we showed that rotational speed is influenced by the amount
of viewpoint-dependent spatial relations but not by viewpoint-independent ones. We can
therefore reject the common assumption that MR always works on pictorial representations.
Furthermore, we were able to divide participants according to the effect of viewpointdependent spatial complexity on their rotational speeds into two strategy groups. As group
membership strongly correlates with sex, it might explain the often reported sex differences
in MR.
Currently, data from a follow-up ERP-study is analyzed. Stimulus-complexity might influence
the rotation-related negativity and this component’s lateralization might differ between
strategy groups. Prospectively, an fMRI study in cooperation with a doctoral student in Medicine will aim for (1) identifying the cortical areas representing the two types of information,
(2) further isolating MR’s cortical bases and (3) exploring the development of the identified
strategies from child- to adulthood and (4) their relation to cortical activation patterns. During my stay in China from September onwards, a large-scale individual differences study will
be conducted. Employing structural equation modeling, we will examine how performances
in three predominant MR-tasks relate and exploit individual differences for isolating cognitive processes, especially those related to visual/visuo-spatial WM.
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Attentional capture by biologically relevant stimuli
Kalina Petrova
Cognitive Psychology Unit, Saarland University
Early detection of danger in the environment is of vital importance for humans. From an
evolutionary, functional perspective, it is therefore reasonable to assume that humans are
prewired to automatically orient their attention towards potential threat. To examine this
question, we have conducted three eye-tracking studies by now. In the first study, we investigated the role that the occurrence of eye movements has in the dot-probe paradigm (Fox,
2002) and found that the manual reaction time bias towards angry faces was significant only
if we excluded the trials in which eye movements occurred, or if participants showed a low
number of trials with eye movements. In addition, the results suggested an eye movement
bias towards threat. To further investigate the effects of threat on the oculomotor system, a
second study was conducted in which participants were required to look away from peripherally presented emotional facial expressions (i.e., the antisaccade paradigm; Hallett, 1978).
Results showed slower antisaccadic latencies with angry compared to happy faces. However,
since the stimuli in this study were task-relevant one might attribute the effect to capture as
well as delayed disengagement of attention. In our third study, we therefore made the emotional stimuli task-irrelevant (Doyle & Walker, 2001). We presented a target, which participants had to look at, up or down. Simultaneously, an emotional face appeared left or right.
In concordance with Doyle & Walker, saccadic trajectories significantly deviated away from
all facial expressions. More importantly, however, this deviation was significantly greater for
emotional than for neutral faces, which suggests that the emotional stimuli produced more
potent competition that in turn required greater inhibition. In an ongoing experiment, we
aim at enhancing participants’ involvement in the task by making the target change its colour depending on participants’ gaze position.
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The representation and activation of evaluative connotations
Melanie Schmitz
Cognitive Psychology Unit, Saarland University
A long-standing debate in the research field of emotion and cognition deals with the question of how the evaluative connotations of semantic concepts are represented within the
semantic memory. For this purpose, evaluative priming (i.e., faster response to a target following a valence-congruent prime compared to an incongruent prime) within a semantic
priming design (e.g., use of the naming task) was considered as an useful paradigm. However, the picture of empirical results is still inconsistent: Evaluative congruence effects as well
as null results or even incongruence effects were reliably found. We test the assumption
that two processes are responsible for these apparently conflicting findings: Whereas congruence effects may be traced back to the target-encoding facilitation by a valencecongruent prime, incongruence effects may be attributed to a prime-activation maintenance
caused by a valence-congruent target: Potential response conflicts (e.g., as prime and target
are associated with different naming responses) are especially pronounced if the primeactivation is maintained and they will slow down the response.
In four behavioral studies, we used a negative stimulus-onset asynchrony between prime
and target to minimize target-encoding facilitation but to maximize prime-maintenance. In
the naming task (Experiment 1), we found significant reversed evaluative priming if prime
and target compete for naming responses. In a semantic categorization task (animal vs. person; Experiments 2/3), the semantic response conflicts between prime and target were significantly higher for valence-congruent than for incongruent prime-target pairs. These results reflect a prolonged activation of valence-congruent primes; a phenomenon that seems
to be valence-specific (Experiment 4). In a further study, ERP correlates of the evaluative
priming effects in the semantic categorization task are examined in order to test the relative
influence of encoding, activation-maintenance and response processes. Implications for the
memory representation of evaluation are discussed.
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Effects of modality-specific Working Memory Training
in learning Chinese and German as a second language
Julia A. Schneiders
Experimental Neuropsychology Unit, Saarland University
Logographic Chinese differs from alphabetic German in aspects of phonology and orthography, which results in differences in brain networks involved in reading Chinese characters
and alphabetic words. Whereas previous research has shown a systematic relationship between phonological working memory (WM) capacity and second language (L2) word learning
for alphabetic languages, for Chinese as a L2 visual working memory should be a better predictor of L2 proficiency due to the greater visual complexity of Chinese characters.
In a first training study we investigated the differential impact of visual and auditory WM
training while Germans native speakers learned Chinese words. Additionally, training induced modulations in language-related brain networks using functional magnetic resonance
imaging (fMRI) were examined. Behavioral data show that both WM trainings led to transfer
effects in orthographic proficiency as compared to a no training control group. Furthermore,
fMRI data revealed a significant decrease in the right middle frontal gyrus for the visual
training group only. In the right visual word form area there was preserved activation for
both training groups but a decrease for the control group.
Our results so far suggest that the training of visual working memory leads to increased
neural efficiency (reduced activation) in the right prefrontal cortex, reflecting facilitated visual WM processes for the processing of Chinese characters as a function of training. Additionally, the training of modality-unspecific processes such as the continuous updating of
working memory representations seems to be beneficial for Chinese orthographic processing
leading to increased recruitment of task-specific processing, as revealed by the preserved
activation in the right fusiform gyrus.
In a second training study we used a complementary design to examine whether auditory
WM training specifically affects L2 learning on a behavioral and neural level when Chinese
native speakers learn German words. Collected data is still a matter of analysis.
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The role of strategic processing for the development of episodic memory retrieval
Volker Sprondel
Experimental Neuropsychology Unit, Saarland University
The development of episodic memory during childhood and adolescence has been suggested
to proceed at different rates for different memory functions, depending on the extent to
which strategic control processes are engaged during retrieval.
For instance, memory for the origin of an event (source memory) is assumed to mature later
than memory for the occurrence of an event (item memory), as source monitoring places
high demands on strategic retrieval processes. These include the recollection of taskrelevant contextual information and the monitoring of retrieval outputs.
The maturation of cognitive control functions extends into late adolescence. To determine
whether these functional improvements in cognitive control map onto age-related changes
in strategic memory retrieval, an important endeavor is to identify the developmental trajectories of item and source memory from childhood to adulthood.
A first study examined age-related changes during childhood and adolescence in item and
source memory retrieval processes by means of event-related potentials (ERPs). The ERPs
suggested no age differences between 8-year-old children, 14-year-old adolescents, and
young adults with respect to recollection-based item memory retrieval. By contrast, the ERPs
revealed developmental changes in source memory across all age groups. Unlike children,
adolescents showed ERP evidence of strategic recollection, along with source discrimination
abilities of equal accuracy as in adults. However, only adults showed the pattern of ERP correlates associated with mature source memory, suggesting that the neural network supporting strategic retrieval continues to refine during adolescence.
Therefore, a second study is currently conducted to investigate developmental changes during adolescence in strategic retrieval processing, operationally defined as a pattern of ERP
indices reflecting the specificity with which cues are processed during source memory retrieval. Age-related differences regarding these indices would contribute to uncover the prolonged developmental course in the control of episodic retrieval.
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Hierarchically organized action representations in memory – Effects of motor similarity
and familiarity on means and ends representations
Katja Umla-Runge
Cognitive Psychology Unit, Saarland University
In my dissertation project, I am interested in the representation of action information in
memory. The main emphasis is on its neural correlates and the mediating factors that determine which aspects we represent.
In Experiment 1 (fMRI), we tested whether domain specific processing regions for action
information are shared in working and long term memory tasks. We found a left hemispheric
network to be commonly activated if action information is to be retained for a short time
and if it is to be retrieved from long term memory. This action network was domain specific
in nature as, for size information, a different network emerged.
Previous studies have shown that neural structures that process means and ends information can be distinguished. In Experiment 2 (fMRI), it was investigated whether that also holds
for retention in working memory and how motor similarity of actions influences activation
levels in action related brain regions. Regions of visual analysis and motor control showed
enhanced activation during retention and target presentation in a means task as compared
to an ends task. Motor similarity modulated activity in some of these regions differentially in
the two tasks. The results can be explained by a model that claims that an action’s ends are
by default represented but its means are optionally represented.
As there are differences in the processing of meaningful and meaningless actions, it could be
that familiarity of an action influences which aspects of an action are represented. In Experiment 3 (cross-cultural + behavioral), we examined whether differences in an action’s familiarity determine if we represent the action’s means in addition to its ends. In the Chinese
sample, we found a differential effect of familiarity on accuracy in a means and ends task.
The data of the German sample are currently analyzed and will also be presented.
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It's worse than expected, but it doesn't matter – Relating cognitive and
affective-motivational theories of performance monitoring
Kerstin Unger
Developmental Psychology Unit, Saarland University
A growing body of evidence for motivational and affective influences on the error-related
negativity (ERN) suggests that this component does not only reflect cognitive facets of error
processing, but also an appraisal of the motivational or affective significance of detected
errors. The aim of this thesis is to shed some light on the relationship between these cognitive and affective theories of the ERN.
In a first experiment we used behavioural measures and event-related potentials to examine
the impact of self-relevant failure on performance monitoring in a reinforcement learning
task. 72 subjects engaged in two consecutive phases (pre- and posttest) of a probabilistic
learning task. After the pretest subjects performed a visual search task announced to be diagnostic for intellectual abilities. Subjects were assigned to one of four groups receiving either failure feedback (group 1, 3) or no feedback (group 2, 4) during this task. For groups 1
and 2 the posttest was linked to intelligence, while it was described as neutral for groups 3
and 4. Results indicated a dissociation between behavioural and ERP effects at posttest. For
the failure feedback groups (1, 3) the ERN increased from the first to the second half of the
posttest, while accuracy did not change. In contrast, for the non-feedback groups the ERN
decreased over the course of the posttest, although performance remained stable (group 2)
or decreased (group 4).
These results suggest that failure experience has an impact on the recruitment of cognitive
control and affective responses to errors in a subsequent learning task. Our data indicate
that failure-induced increases of the ERN may be unrelated to performance and hence
strongly suggest that affective theories may explain variation in the ERN over and above the
variability explained by cognitive theories.
A second study will set out to directly contrast the consequences of affective manipulations
(stimuli and context) on the neural networks involved in performance monitoring.
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Spatial-perceptive disorders and spatial neglect:
Neuroanatomy, clinical findings and vestibular modulation
Kathrin S. Utz
Clinical Neuropsychology Unit, Saarland University
Right-Brain-Damage (RBD) often causes spatial neglect and spatial-perceptive disorders impairing rehabilitation. My doctoral project aims at a deeper understanding of both and studies 3 main aspects: a) the neuroanatomy of spatial-perceptive disorders and spatial neglect,
b) clinical studies, c) modulation studies.
Neuroanatomy: 30 RBD patients conducted several spatial-perceptive and neglect tests.
Their performance will be correlated with the lesion overlap of the patients´ structural MRI/CT-Scans (MRIcro, Rorden & Brett, 2000) to identify crucial brain areas.
Clinical studies: It has previously been observed, that RBD patients with (RBD+) vs. without
neglect (RBD-) show a tilt of the subjective visual vertical and subjective haptic vertical (SVV,
SHV) in the roll plane. Saj et al. (2005) extended this finding by showing backward tilts in the
sagittal SVV. We observed a comparable tilt also for the SHV. In parallel collaborative studies
head-position (Funk, Finke, Muller, Utz, & Kerkhoff), and contextual cues (tilted frame) induced pathological verticality judgments in RBD+ vs. RBD- patients (Funk, Finke, Müller, Utz
& Kerkhoff, submitted).
Modulation studies: Galvanic Vestibular Stimulation (GVS) modulates cortical excitability via
application of weak direct currents leading to an activation of the cortical vestibular system.
First, we conducted a detailed review of the state of the art in GVS and transcranial direct
current stimulation (tDCS), a related brain stimulation technique (Utz, Dimova, Oppenlander,
& Kerkhoff). Second, we investigated the side effects of 255 sessions with GVS conducted in
post-stroke patients and healthy individuals via self-ratings in a questionnaire. Apart from
mild tingling and itching sensations underneath the electrodes no side effects occurred, indicating that GVS is safe.
Several ongoing studies reveal that a) GVS modulates the tilt of the SVV+SHV, b) reduces the
error in line bisection in neglect, c) improves arm position sense (Schmidt, et al., 2010) and
d) reduces tactile extinction (Kerkhoff et al., submitted).
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Cross-cultural action acquisition and representation in children
Lamei Wang
Institute of Psychology, Chinese Academy of Sciences, Beijing
Developmental Psychology Unit, Saarland University
The aim of this project is to study the importance of means and ends in children’s action
acquisition and action representation under a cross-cultural perspective. The imitation paradigm is used to test action acquisition and recognition memory paradigms will be used to
test action representation. We expect the factors familiarity and complexity to play an important role, that is, we expect actions that are known to be represented in terms of ends
and actions that are unknown to be represented in terms of means. Moreover, this should
be modulated by the complexity of the action. However, no cross-cultural difference is expected.
In a first step, we conducted a pilot study in which 68 video clips showing short manual actions on objects were rated by 20 adult subjects from each culture concerning familiarity and
complexity (two categories each). This rating procedure resulted in 32 actions (8 actions for
each factor combination). In the imitation study, 32 preschoolers from each culture were
tested. The imitation score, duration of imitation and imitation error type were coded by
two scorers. Preliminary results indicate the expected main effects for complexity and familiarity with no interaction between the two factors. Only one significant difference between
two cultures was obtained: Chinese preschools outperformed German children in the complex actions if they are known. Interestingly, gender difference was only found among German children. Boys showed better performance than girls when simple actions were to be
imitated.
For the recognition study, each action video was developed in four versions – the original
one, a means-changed version, an end-changed version and a distracter, in which means and
ends were both changed. The aim of this recognition study is to investigate how complexity
and familiarity differentially influence action representation in terms of means and ends.
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Predicting school success: The role of working
memory capacity, motivation and family influences
Heike S. Weber
Individual Differences and Psychodiagnostics Unit, Saarland University
The main goals of this study are to determine the relative contribution of cognitive and noncognitive variables (e.g., motivation and involvement) to the prediction of school success
and to compare their interaction across cultures. Family and other environmental influences
provide the setting in which achievement behavior develops and is carried out. Thus, between family differences regarding parental involvement on the one hand as well as interindividual differences concerning motivational constructs on the other hand are compared and
analysed.
Whereas it is common to measure general intelligence in the field of educational research,
we also assessed Working Memory Capacity as a main cognitive variable in order to investigate its often discussed predictiveness in school context. The simultaneous assessment of
Working Memory Capacity and non-cognitive variables in one study is a new approach in the
context of school achievement in young children.
Until now, a German sample of 320 fourth graders was tested in school to assess Working
Memory Capacity and Intelligence. Non-cognitive and family variables were measured via
questionnaires answered by the children and parents at home. In Beijing, an assessment
including the same but adapted test materials was conducted covering a sample of 200 Chinese fourth graders.
One main finding is that both cognitive factors are of great importance to the prediction of
school success. But motivational constructs also play a role. Whereas in Math cognitive predictors show a higher predictive validity compared to motivation, the opposite is true for
German. In this subject, the child´s self-perceived ability turned out to be the strongest predictor.
In a next step, more complex models which also include parental involvement and socioeconomic factors will be analysed. The results found for the German sample will be contrasted to results from the Chinese data set.
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