Invited addresses

[5 abstracts]

1. Optical-geometrical illusions: A list of problems  
Vicario G. B.
Università di Udine, Udine, Italy

A list of problems to be solved sooner or later in investigations on optical-geometrical illusions is set forth. (a) Etymology. Optical-geometrical illusions are no "errors": illusions are surprising and unavoidable (e.g., Delboeuf, 1892*25), while errors are admitted and corrigible (e.g., Tolansky, 1964*26). (b) Naming and definition. Names and definitions are countless: optical-geometrical illusions (Oppel, 1855; Wundt, 1898; Rausch, 1952; Metzger, 1975), optical illusions (Delboeuf, 1865a; Pegrassi, 1904; Ehrenstein, 1954; Tolansky, 1964; Imai, 1984), optical paradoxa (Brentano, 1892), optical illusions of judgement (Müller-Lyer, 1889), visual illusions (Luckiesh, 1922; Robinson, 1972), illusions (Goto & Tanaka, 2005), figures trompeuses (Delboeuf, 1865b), inadequate representations (Benussi, 1906), and so on. (c) Phenomenology. Looking at some displays we feel to be in front of an illusion (e.g., Oppel, 1855*5), while looking at other ones we cannot see anything dubious (e.g., Ebbinghaus, 1908*82). (d) Nomenclature. It is at least chaotic, ranging from the name of the discoverer to the effect observed or to the supposed underlying mechanism. (e) Classification. The author is acquainted with 24 classifications of optical-geometrical illusions, but probably every scholar of the field can exhibit his own classification. (f) Delimiting the field of research. Too often optical-geometrical illusions are mixed with heterogeneous phenomena, like anomalous surfaces (Schumann, 1900a*7), masking (Metzger, 1975*79), impossible objects (Penrose & Penrose, 1958), alternating ambiguous figures (Boring, 1930, 444), coexisting ambiguous figures (Schuster, 1970*1), reversible figures (Necker, 1833*18; Schröder, 1858*12-13), brightness contrast (Kitaoka et al., 2004*6CF). (g) Pictorial perception. There is to settle the question whether the numerous optical-geometrical illusions involving two-dimensional representations of solids (to begin with Thiéry, 1895a*2, and Filehne, 1898*23) are indebted with pictorial perception (Gibson, 1954) or not. (h) Whole-parts relation. This relation is manifold and often indecipherable: sometimes parts influence the whole (Schumann, 1900b*6) and sometimes the whole influences parts (Sander, 1926b*9-I), but there are also cases by which influence is supposed but not perceivable (Vicario, 2006b*11.3) or not demonstrable (Vicario, 2006, unpublished). (i) Optical-geometrical illusions and everyday experience. There is a hýsteron próteron figure in the question: optical-geometrical illusions do not exist "also" in everyday experience (see, for instance, Höfler, 1896*2; Metzger et al., 1970*2a, Vicario, 2001*40) - they take place in everyday experience and therefore "also" in drawings or pictures, which are impoverished images of the actual environment. (j) The measure of illusions. Fisher's (1973) argument on the impossibility of obtaining a true measurement of illusions is demonstrated (Vicario, 2008, unpublished) and developed. (k) Why do optical-geometrical illusions exist? Adaptive behaviour, phylogenetically developed, should exclude their presence. A possible solution of the problem is to suppose that the evolution of perceptual systems is a matter of costs/benefits.

2. Neurodynamics of figure-ground organization  [presentation, ppt, 3911 kB]
Domijan D.
University of Rijeka, Rijeka, Croatia

Figure-ground organization is an important early step in visual processing. It separates structured input to which processing efforts should be devoted (figure) from less structured background. Gestalt psychologists identified several variables which influence figure-ground assignment, including size, contrast, surroundness, and convexity, symmetry, parallelism and horizontal-vertical axes. Recently, several new factors affecting figure-ground organization were discovered. Those are lower region, top-bottom polarity, and extremal edges. Early neurophysiological investigations of figure-ground assignment found enhanced firing rate in the primary visual cortex of monkeys. Activity enhancement was observed in the region which corresponds to the perceived figure in texture segregation task. On the other hand, recent investigations revealed a special group of neurons in the visual cortex which detect border ownership. The figure is distinguished from the background by different responses to the same boundary. If the figure is on one side of the boundary, a certain neuron will fire, but if the figure is on the other side of the same boundary, the same neuron will be silenced and another neuron will show an enhanced firing rate. There are many computational models proposed to explain the properties of figure-ground organization. Several models focused on the boundary assignment alone. Other models are concerned with explaining psychophysical findings. Although the models share some common assumptions, there are also important differences between them. Border ownership models could not explain many of the identified Gestalt principles of figural assignment. On the other hand, psychophysical models are based on the assumptions that are not supported by the neurophysiology. Important problem for the future research is how to reconcile psychophysical and neurophysiological models in order to provide a unified account of the figure-ground organization.

3. Narrative psychological content analysis in studies of therapeutic impact  
Péley B.
University of Pécs Institute of Psychology, Pécs, Hungary

Impact of psychotherapy is a long disputed issue in clinical psychology. Westen and Weinberger (2004) depict the studies along the coordinates "Method of Aggregation" x "Type of Informants". Method of aggregation can be statistical vs. informal, whereas the source of data can be either the patient (self report) or the clinician (clinicians report). The two coordinates give four quadrants. The authors claim that whereas two quadrants are heavily loaded, "Until recently, virtually no research has addressed the quadrant, which crosses clinical observation with statistical aggregation". There are also missing studies working with informal data collection from the patients’ self reports. This lack of research is partly due to the reluctance of researchers for dealing with interpreted data statistically. One of the major advantage of the narrative psychological content analysis is that it has the capacity to give diagnostic judgments on the patient’s psychological states, which are based on her informally occurring narrative discourse, and these data are apt to statistical aggregation. A further advantage is that whereas the frequency of using objective tests, which are easily amenable to statistical analysis, is limited in the course of a therapy, discourse samples are available in a non-intrusive way, and content analysis works as a quasi on-line methodology. The lecture presents the results of a pilot study, which compared efficiency of the cognitive scheme therapy with that of the short dynamic therapy along the changes in the therapeutic discourse. Narrative patterns that were quantified in this study included activity-passivity (agency), mentalization, intentionality, evaluation, and characters' psychological functions. Activity-passivity dimension was measured by an algorithm based on a dictionary of active verbs (e.g. do, construct, etc.) and passive verbs (e.g. sleep, stand, etc.) and on local grammars specifying the use of these verbs with meaning of activity and passivity. The algorithm involves partial syntax for identifying passive voice. Similar grammars were built for intentionality. The intentionality algorithm distinguishes between wishes (e.g. hope) and intentions (e.g. want) as well as between "musts" (e.g. ought, must, should) or possibilities (e.g. may). The mentalization algorithm includes three subscales: emotionality, intentionality and cognitive processes. Each subscale is constructed with the logic described above. The emotion algorithms of course handle with adjectives and adverbial forms. Samples of therapeutic discourse were analyzed with the above tools. Therapists gave parallel evaluations on the sessions and on the progress of the patients. In both therapy types systematic changes could have been observed in the course of the therapy; e.g. at sessions, where therapists perceived progress, frequency of activity and intentionality increased.

4. Brain-computer interfacing and neurofeedback  
Neuper C.
Department of Psychology, Section of Neuropsychology, University of Graz, Graz, Austria

Brain-computer interfaces (BCI) connect the living human brain with an external system. Motivated by the idea of controlling machines not by manual operation, but by "mere thinking", researchers working at the crossroads of neurosciences, computer science, biomedical engineering and psychology have joined forces and started to develop first prototypes of BCIs over the last decade. Common goals are, for example, to develop novel communication devices, neural prostheses, and therapeutic tools to assist people with severe motor disabilities. Such a BCI system uses a person's brain activity, i.e. specific features automatically extracted from the recorded brain signals, to operate computer controlled devices. Herewith, the system translates particular intentions into actions – such as moving a wheelchair, selecting a letter from a virtual keyboard, or grasping with the aid of a neuroprostesis. The neuronal activity of the brain can be recorded non-invasively with electroencephalography, magnetoencephalography, and imaging technology as well as invasively with electrocorticography or intracortical recordings. Within a closed loop, users are provided with visual, auditory, or tactile feedback of a specific component of their brain activity which enables them, to some extent, to regulate this activity. In many studies it has been shown that patients with severe motor impairment can learn to communicate and control devices by means of a BCI. Moreover, newly developed BCIs offer promise for clinical therapy and rehabilitation to improve motor and cognitive function and to influence emotional reaction. There are still some technical problems to overcome to broaden the field of BCI application, but especially the influence of psychological variables on BCI performance remains to be elucidated in further research.

5. Recent developments in child personality research  [presentation, ppt, 2424 kB]
Zupančič M.
Department of Psychology, University of Ljubljana, Ljubljana, Slovenia

A relative agreement on the Five-Factor Model to summarize the organization of personality traits in adults in many countries and language communities has been established (e.g., McCrae & Costa, 1997). Although the model has its critics, its value has also been enhanced when developmental precursors of the five domains were identified. In addition to Digman's work (1963, 1989), recent studies of children living in different societies provide compelling evidence that children are perceived by adults in terms of traits that are markers for the general FFM (e.g., Kohnstamm et al., 1998). This presentation will focus on personality trait research in children and early adolescents with a special attention to ongoing studies in Slovenia. Strategies to assess personality in non-adult age groups are reviewed and the free descriptive strategy is emphasized: (a) findings suggest that adults describe even infants/toddlers in terms that are predominantly categorized into the FFM taxonomy and distributions of descriptors show developmental patterns; (b) based on parental free descriptions of children across countries, ecologically valid assessment tools were created. The ICID (Halverson et al., 2003) is also conceptualized as an age and culture neutral instrument, it is widely used in Slovenia and is currently being normed. Several aspects of consistency in personality traits from early through middle childhood using the ICID, longitudinal and multiple-informant approach will be presented (structural, normative, rank-order, ipsative), as well as the aspects of consistency across contexts/informants. Cross-sectional studies on ratings of 3- to 14-year-olds provide information on age, sex, and culture differences in child personality trait expression. In addition to the trait-centered approach, results based on the child-centered approach suggest 3 to 4 internally replicable personality types. The predictive validity of traits vs. types will be discussed from a developmental perspective. Concurrent and longitudinal predictive value of child/adolescent traits was found for several outcomes: emotional and social adjustment, sibling relationships, differential parenting, academic skills, academic motivation and achievement. Prospects for future research on personality development will be discussed, including assessment, at risk samples, preventing behaviour problems, and promoting competence.