List
of talks
Abstracts
Robert
Hughes:
A Negative Order-Repetition Priming Effect: Inhibition of Order in
Unattended Auditory Sequences? A
novel negative priming effect is reported in which recall accuracy for a sequence
of visually presented digits was significantly poorer if the same sequence (Experiment
1) or a portion of that sequence (Experiment 2) was presented as an irrelevant
auditory distractor sequence on the previous trial. An enhancement of the effect
was obtained in Experiment 3 when participants divided their attention between
the to-be-remembered sequence and the to-be-repeated auditory sequence. The results
of Experiments 1 and 2 provide converging evidence that auditory events are seriated
despite being unattended. Given the result of Experiment 3 however, a further
experiment will be required to determine whether the source of the negative direction
of the effect is best accounted for in terms of the inhibition of the to-be-repeated
sequence, or an incongruence arising from a mismatch in the repeated presentation
of the sequence in terms of sensory modalities. 
Ben
Wellens:
The Combined Effects of Occupational Noise Exposure and Temporal Stressors
on Human Error: Accidents, Minor injuries, Cognitive Failures and Human Performance.
There
is a rich history of researching the effects of various factors (i.e. noise, night
work, job demand etc) on health outcomes (i.e. stress, performance, illness absence
etc) in the work environment. However, the complexity of the work environment
is rarely addressed and the potential for additive or synergistic combined effects
is not widely considered. Laboratory studies have been used to manipulate certain
combinations of stressors, i.e. noise and night work (Smith & Miles, 1986, 1987).
The data presented here is an attempt to address the combined effects of noise
and night work (and other temporal stressors such as shift work, unpredictable
and long hours of work) using a variety of other methods seldom used including
epidemiological techniques. Ecological validity was an issue in the laboratory
studies. By studying these stressors in the working population, ecological validity
will be increased. Preliminary findings suggest that it is often the influence
of one major stressor (i.e. loud noise) that would account for deficits found.
Where combined effects were seen, it was the combination of a series of minor
hassles (i.e. noise annoyance, unsocial work hours) that combine to account for
deficits found. Occupational noise exposure was seen to have a greater negative
impact on human error than temporal stressors. There are a number of methodological
issues that need to be addressed. Potential for future directions will also be
discussed.
Bill
Macken:
Transitional Probabilities and the Mind (There's no such thing as memory,
part II) Many
traditional accounts of memory hold that there are some sort/s of stores and/or
processes that are there to retain information over various periods of time. Contrary
to this, I'll attempt to argue that there are no such 'bespoke' processes or stores,
but rather that there are a range of symbolic skills that may be flexibly co-opted
to perform tasks that require the retention or manipulation of information in
real time.
Fiona
Harrison:
Visual Spatial Attention and Drug Manipulations in Aged Rats. One
of the major accounts of Alzheimer's disease (AD) is based on damage to the basal
forebrain cholinergic system. Four drugs which all affect this system - Tacrine
(a cholinesterase inhibitor), Cytisine (a nicotinic agonist), Thioperamide (a
histamine antagonist), and CGP-62349 (a GABAB antagonist) - were administered
to aged rats (18 - 22 months) which had been classified as either impaired or
normal according to their performance at baseline level on the Five Choice Serial
Reaction Time Task (5-CSRTT) which is a test of visual attention. Human AD patients
have been found to be impaired on an analogous touch-screen version of this task,
and the four drugs were assessed as to how well they were able to ameliorate the
rats' performance on several measures including accuracy and response latencies.
Normal rats were tested with a shortened stimulus duration to increase their attentional
load and decrease their performance levels to mirror the performance of the impaired
group. Each of the drugs was found to lead to a different pattern of results,
regardless of group. Moreover, each drug affected the impaired and normal groups
differentially, with significant effects being seen on different measures for
each group.
Alex
Payne:
Risk and Protective Factors associated with Social Information Processing,
Executive Function, Theory of Mind and Emotion Regulation in the Emergence and
Development of Aggression in Childhood. Social
information processing, executive function, theory of mind and emotion regulation
have all been implicated as risk and protective factors in the emergence and development
of aggressive behaviours in childhood. The aims of the study are to investigate
the relationships between these cognitive and affective variables in attempting
to explain the underlying mechanisms of aggressive behaviours. Differences in
these phenomena as a function of gender, age and presenting symptoms will also
be examined. Participants will be approximately 120 children aged 9, 10 and 11
years and their teachers from mainstream primary schools throughout South Wales.
A second study of children with more extreme behavioural problems will be undertaken
in special schools. The children will take part in a 2 hour interview in which
they will complete measures of their level of conduct problems, social information
processing, emotion regulation, executive function and theory of mind on both
a group and individual basis. The hypotheses are as follows: There will be an
association between theory of mind and executive function. Theory of mind will
significantly influence social information processing. Executive function will
significantly influence social information processing. There will be an association
between social information processing and emotion regulation. Social information
processing will significantly influence the occurence of aggressive behaviours.
Emotion regulation will significantly influence the occurrence of aggressive behaviours.
Preliminary findings suggest that there is support for the hypotheses, although
there are insufficient data at present to draw any firm conclusions. Data collection
is still in progress.
Nicholas
Perham:
How to make friends and scare people. To
induce an anxious mood in participants we used a technique used by Burke and Mathews
(1992). Participants were shown a series of either physically threatening, socially
threatening or neutral words. They were told to imagine personal situations involving
each word and describe the situation for 10 seconds. Galvanic skin conductance
(GSR) measurements, State-Trait Anxiety Inventory (STAI: Spielberger, Gorusch,
& Lushene, 1970) scores and reaction times were recorded. STAI scores and reaction
times showed that those who saw the physically and socially threatening words
were significantly more anxious, and took longer to think of events than those
who saw the neutral words. However, the GSR data were less conclusive.
Gregory
R. Maio, Susan E. Watt, and Miles Hewstone:
Effects of Anti-Racism Messages
on Intergroup Attitudes. The
present research investigated whether the effect of anti-racism messages on implicit
and explicit attitudes toward ethnic groups depends on the message recipients'
initial ambivalence toward the groups. In two experiments, participants took part
in a pre-test session, which measured several attributes of their attitudes toward
ethnic minority people (e.g., valence, embeddedness), including ambivalence. Several
months later, participants were exposed to an anti-racism message. In Experiment
1, participants read either a flawed anti-racism editorial that argued in favour
of increased quotas for immigration to Britain or a neutral filler editorial.
In Experiment 2, participants read either an anti-racism advertisement or a control
advertisement. Results indicated that exposure to the anti-racism editorial or
ads positively influenced nonambivalent participants' implicit and explicit intergroup
attitudes, whereas the anti-racism message negatively influenced ambivalent participants'
intergroup attitudes. Overall, these results help determine which target audiences
may be most affected by persuasive messages against racism.
Helen
Hodgetts:
Interruptions in the Tower of London. The
negative effect of interruptions is evident in both laboratory studies and real
life situations, degrading performance by way of increased task performance time
and decreased accuracy. Using the Tower of London problem, a series of experiments
examined the effects of task interruptions on performance in terms of time taken
to execute each move and number of errors made. As predicted, time taken for participants
to execute a subsequent move in their plan was longer when stopped mid-task by
an unexpected interruption than when plan execution was allowed to be continuous,
with the extra time taken reflecting that needed to reconfigure the task set following
an interruption. The position of the interruption was varied, occurring either
at the beginning, middle or end of the plan execution; those occurring in the
middle were found to cause more degradation of performance as indexed by both
errors made and time taken. The length of the interruption, however, appeared
to have little influence on error rates or time needed to resume the primary task.
Lisa
Evans:
Prepulse Inhibition in Schizophrenia: What is the Nature of the Deficit?
A
large body of literature indicates that schizophrenic patients have an inability
to inhibit distracting, trivial or non-salient information. One way that this
has been measured empirically is by using the Prepulse Inhibition (PPI) paradigm.
This refers to the suppression of the startle reflex when a weak prepulse precedes
the startling stimulus by around 120 ms. Previous work has documented that schizophrenic
patients have a deficit in their PPI, however, its exact nature and extent is
unknown. There is also the issue as to whether performance on PPI is modified
by certain symptom profiles. A number of researchers have found that deficits
on PPI are associated with the positive symptoms of psychosis, whereas others
have found that they are associated with negative symptoms. Hence, this is an
area which needs further exploration. Another avenue of research that we are taking
is to adopt the continuumist approach to schizophrenia and studying the relationship
between the personality trait of schizotypy and PPI performance. Theoretically
it would be expected that individuals high in this trait might show the same pattern,
albeit on a much milder scale, to those individuals with schizophrenia. These
are the issues that we are currently investigating and which I will elucidate
upon in this presentation.
Jenny
Naji:
Pursuit Eye-movements can Disambiguate Depth Order in an Ambiguous Motion
Display. Motion
gradients can be used to specify 3-dimensional surfaces. If a corrugated sheet
is moved with respect to an observer, the closer peaks of the corrugation move
faster across the retina than the farther troughs (the faster-nearer rule). This
allows the visual system to determine the relative depth order of objects. This
type of corrugated surface can be specified by two kinds of motion gradients:
relative motion (shear) and translation. If an accurate eye movement is used to
track this kind of surface, this would effectively 'cancel' the retinal translation.
Does this change our perception of the depth of a surface? To investigate this,
we looked at three types of display: 1. Relative motion accompanied by translation
(eye stationary); 2. Relative motion (eye stationary) and 3. Relative motion with
translation accompanied by a pursuit eye movement. For the faster-nearer rule
to be employed, thus theoretically disambiguating depth order, there must be both
shear and translation in the display. It can be seen from this that we would predict
the depth order in condition 1 to be unambiguous and the depth order in condition
2 to be ambiguous. In condition 3 however, the case is not as clear-cut. In order
for this surface to be perceived unambiguously, an extra-retinal estimate of translation
would be needed. Indeed, this is what we found: observers are able to correctly
determine the relative depth order of stimuli in conditions 1 and 3 (according
to the faster-nearer rule) but the stimulus appears ambiguous in condition 2.
This suggests that it is the component of translation that is disambiguating depth
order, either from an extra-retinal estimate of translation (3) or from a retinal
estimate (1).
Olivia
Handley:
Genetic and Cognitive Profiling of Alzheimer's Disease: The Influence
of Genotype on Pathological Cognitive Decline. A
major risk factor of Alzheimer's disease (AD) is the apolipoprotein gene (ApoE)
found on chromosome 19. It has been shown that this gene, specifically the e4
allele, is associated with cognitive deficits typical of AD patients. However,
considerably less research has ventured into the prevalence and effect this gene
has on populations at normal and 'at risk' of developing AD. Participants aged
between 61-84 years, consisted of 20 unaffected siblings of late-onset AD patients
and 20 matched controls. A comprehensive battery of cognitive tests was administered
to all participants, together with analysis of genotype, specifically ApoE status.
Cognitive performance was assessed using two approaches: comparisons between both
sibling and control groups and comparisons according to ApoE status. Preliminary
results indicated differences between siblings and controls for cognitive performance
but only for a subset of tests. In comparing different genotypes, carriers of
at least one copy of the e4 allele displayed a more generalised deficit in cognitive
processing than non-carriers. Future research will aim to recruit larger population
samples to locate stronger genotype differences within sibling and control groups.
Consequently, how these differences influence cognitive performance will be established.
The aim is to provide greater insight into the predicative power of a combination
of cognitive factors/genetic risk factors for the development of AD, and more
importantly, the extent to which this gene can be used as a deterministic rather
than associative gene in predisposing AD.
Simon
Banbury:
The Development of an Implicit Situation Awareness Toolkit. Much
of the knowledge that an experienced system operator uses is procedural, rather
than declarative, and as a result this knowledge may not be available to conscious
inspection. It is proposed that to access this tacit or 'implicit' knowledge,
Human Factors practitioners need to employ implicit knowledge probes. This paper
provides a rationale for testing Situation Awareness (SA) implicitly and an overview
of an 'Implicit SA' toolkit. This CD ROM-based toolkit provides Human Factors
practitioners with step-by-step guidance on how to measure Implicit SA - the aim
being to supplement and enhance (rather than replace) existing explicit SA measurement
techniques. The toolkit permits a user to design a bespoke test for measuring
implicit SA from scratch. It guides the user through the design and construction
stages of an implicit test in a self-explanatory manner and provides details on
methodologies, number of participants required, experimental design, and so on.
It also provides examples of previous applications for each test and imparts substantial
background information pertaining to implicit knowledge, memory, and learning.
Claire
Miles:
Marital Conflict and Child Adjustment: Both Sides of the Story. Understanding
the conditions that account for increasing rates of psychological distress among
children has become a significant domain of enquiry for psychologists, psychiatrists
and other mental health professionals. Family factors such as parent psychopathology,
family economic strain, parent substance abuse, divorce and separation as well
as conflict between parents have been linked to increases in children's symptoms
of depression, aggression, anti-social behaviour, delinquency, low social competence
and academic underachievement. The role of conflict between parents has received
considerable attention as an explanatory factor in recent years and, indeed, has
been shown to mediate the effects of other family factors on children. Indeed,
children exposed to conflict between parents that is frequent, intense, child-related
and poorly resolved has been shown to be more upsetting to children of all ages
than conflict that is expressed without animosity, concerns a topic unrelated
to the child and is successfully resolved. The present study focuses on the role
of children's feelings of threat and self-blame following arguments between their
parents in accounting for increases in their internalising symptoms (depression,
anxiety, withdrawal) and externalising problems (aggression, hostility and anti-social
behaviour). Attention will also be directed toward identifying specific risk and
protective factors that help explain why some children respond negatively to the
conditions of marital and family conflict while others remain relatively unaffected.
Orazio
Giuffrida:
Semantic Memory Organisation in Bilingualism. Historically,
the debate concerning semantic memory organisation in bilinguals proposes two
main theories. The first theory is a unique semantic store, the second is two
or more different stores (Brown, Sharma, & Kirsner 1984; Gerald & Cortese 1984;
Altariba 1990). Recently, a third theory was proposed by Kroll and Stewart (1994).
The theory suggests a developmental model with two different translation routes:
from first language (L1) to second language (L2), versus from L2 to L1. Twenty-nine
Italian-English bilinguals completed a preliminary task used in order to place
participants into two main conditions (L1 dominant or L2 dominant). The subjects
were presented with three lists of to-be-translated single words. Each list was
divided in translation from L1 to L2 and from L2 to L1. The first list was composed
of words semantically unrelated, the second semantically organised, the third
of cognate words. The reaction time of each translation was recorded. Significant
statistical differences were found on the L1 dominant group in each condition.
No statistical differences were found on the L2 dominant group. The results are
in accord with the Kroll and Stewart (1994) theory. However, the present research
seems to suggest that this model needs to be refined for highly fluent bilinguals.
Michael
Dunn:
The Role of Dopaminergic, Serotonergic and Glutamatergic Pathways in
Conditional Discrimination: Implications for an Impairment of Contextual Processing
in Schizophrenia. Schizophrenia
has long been associated with a broad spectrum of cognitive and behavioural deficits
including perturbations of arousal, problem solving and linguistic processing.
Traditionally, 'animal models' of schizophrenia (e.g. Latent Inhibition and Pre-pulse
Inhibition) have exemplified impairments in selective attention. It has recently
been suggested, however, that a central core deficit in the ability to construct,
maintain and modify contextual information, and to use this information for goal
directed behaviour, may account for many of the observed deficits. Tasks in which
patients with schizophrenia show consistent and often profound impairments all
require as an essential prerequisite for successful performance this ability to
process contextual information. Using a conditional discrimination paradigm, rats
were trained to lever press for pellet reinforcement. Reinforcement was, however,
contingent upon a correct response i.e. left or right lever, given during presentation
of either one of two auditory stimuli (context) i.e. tone or clicker. Animals
were then challenged systemically with either the indirect dopamine agonist d-amphetamine
or the non- competitive NMDA antagonist Phencyclidine (PCP), both reliable schizophrenomimetics.
Both were shown to selectively disrupt conditional discrimination, however, this
disruption was attenuated by various antagonists. When both antagonist and d-amphetamine
were given chronically, the atypical neuroleptic Clozapine and also Flupenthixol
but not a selective D2 antagonist or typical neuroleptic Haloperidol, blocked
the disruptive effects of d-amphetamine suggesting D1 and 5HT involvment. Clozapine,
Flupenthixol and the selective D1 antagonist SCH 23390 all blocked amphetamine
disruption when given acutely. However, when antagonists alone were administered
chronically before a single dose amphetamine challenge, only the selective D2
antagonist Eticlopride attenuated amphetamine disruption. The results highlight
a potentially important D1 & D2 interaction and the implications this may have
in the design of pharmacological interventions.
Hansjörg
Neth and Stephen J. Payne:
Towards a Theory of Learning by Not Doing. In
order to learn how to solve a problem a good idea might be trying to solve it.
Incidental learning ('learning by doing', Anzai & Simon, 1979) then appears as
a mere by-product of problem solving activity. An alternative approach might involve
a deliberate decision to learn more about a problem without actually solving it
('learning by not doing'). According to Kirsh and Maglio (1994) actions with the
intent to learn more about a problem can be characterized as 'epistemic', and
contrasted with goal directed attempts to solve a problem ('pragmatic actions').
In traditional studies of problem solving, both modes are intertwined and indistinguishable.
Using a classic transformation task (Towers of Hanoi) we are trying to induce
and isolate epistemic actions (by instruction or device support) and assess their
consequences on problem solving performance and learning.
Jacky
Boivin:
Do Psychological Factors Influence Fertility? Evolutionary
research on non-human mammals has shown that under conditions of extreme stress
the reproductive system shuts down preventing conception (c.f. Wasser, 1983).
At the same time most of us know that babies are frequently born to families exposed
to conditions which produce considerable stress (e.g., war). This paper will review
the evidence for a link between stress and fertility potential in humans.
Barrie
Edmonds:
The Effect of Consistency in Across Frequency Interaural Delays on
Speech Intelligibility in Noise. It
is easier to understand speech in the presence of noise or other speech if the
target and its interferer have different interaural time delays (ITDs) - this
is called binaural advantage. We tested the importance for this effect of providing
a consistent target ITD across different frequency regions. In Experiment 1, participants
were required to transcribe target sentences presented in a background of brown
noise (presented with zero ITD). Target sentences were presented as a pair of
high- and low-pass bands separated by a 1-ERB notch centred at frequencies of
750, 1500, or 3000 Hz. Speech reception thresholds (SRTs) were measured for three
configurations of target sentence ITDs: baseline (high and low band with zero
ITD), consistent (high and low band both with +0.5 ms ITD) and inconsistent (high
and low band with different +/- 0.5 ms ITDs). Results from 18 participants showed
that SRTs from the consistent and inconsistent conditions were significantly lower
(~3 dB) than those measured for the baseline condition and indistinguishable from
each other. No effect of notch frequency was observed. In Experiment 2, SRTs were
obtained for the same conditions, but with a single voice as the background interference.
The results for 18 participants were similar to those of Experiment 1, except
that the SRTs in the consistent and inconsistent ITDs were only 1.8 dB lower than
in the baseline condition. Thus, these results indicate that for the intelligibility
of speech in the presence of an interferer the target does not need to occupy
a consistent perceived location for binaural advantage to be obtained. The only
important factor is the difference in binaural cues between target and interferer
within each frequency band.
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