Using neural response properties to draw the distinction between modal and amodal representations

ABSTRACT

Barsalou has recently argued against the strategy of identifying amodal neural representations by using their cross-modal responses (i.e., their responses to stimuli from different modalities). I agree that there are indeed modal structures that satisfy this “cross-modal response” criterion (CM), such as distributed and conjunctive modal representations. However, I argue that we can distinguish between modal and amodal structures by looking into differences in their cross-modal responses. A component of a distributed cell assembly can be considered unimodal because its responses to stimuli from a given modality are stable, whereas its responses to stimuli from any other modality are not (i.e., these are lost within a short time, plausibly as a result of cell assembly dynamics). In turn, conjunctive modal representations, such as superior colliculus cells in charge of sensory integration, are multimodal because they have a stable response to stimuli from different modalities. Finally, some prefrontal cells constitute amodal representations because they exhibit what has been called ‘adaptive coding’. This implies that their responses to stimuli from any given modality can be lost when the context and task conditions are modified. We cannot assign them a modality because they have no stable relation with any input type.

Abbreviatons: CM: cross-modal response criterion; CCR: conjuntive cross-modal representations; fMRI: functional magnetic resonance imaging; MVPA: multivariate pattern analysis; pre-SMA: pre-supplementary motor area; PFC: prefrontal cortex; SC: superior colliculus; GWS: global workspace     

Knowing how to look predicts the ability to draw realistically

Some young children are able to create stunningly realistic drawings resembling those of adult artists. What perceptual abilities underlie this talent? This study examined two candidate skills on which adult artists excel: the ability to segment a complex form mentally (measured by the Block Design Task) and the ability to see hidden forms (measured by the Group Embedded Figures Test). Sixty‐seven 6‐ to 13‐year‐olds with a wide range of drawing abilities completed these tasks as well as an IQ test and an observational drawing task. While children who scored high on drawing realism outperformed those who scored low in drawing realism on both perceptual tasks, only detection of embedded figures predicted drawing realism. This occurred independently of age, gender, years of training, and verbal and non‐verbal IQ. There are certainly many contributors to this complex ability, but one component appears to be the tendency to see things more as they really are and thereby recognize the continuous contour of an object despite interference from other overlapping objects.     

Creating coherence in real‐life decision processes: Reasons,differentiation and consolidation

Svenson, O. & Jakobsson, M. (2009). Creating coherence in real‐life decision processes: Reasons, differentiation and consolidation. Scandinavian Journal of Psychology, 51, 93–102. Differentiation and Consolidation Theory describes human decision making as a process in which attractiveness values are restructured in order to reach a decision and support the decision made. Here, the theory was developed to include reasons pro and con alternatives and tested on students making decisions between two university psychotherapy training programs (cognitive‐behavioral and psychodynamic therapy). Before and also after the decision, the attractiveness of the chosen alternative was upgraded and the non‐chosen alternative downgraded. Different measures of evaluations of an alternative, such as “best” or “worse” converged over time until shortly after the decision. The number of reasons pro and con alternatives give a more complete picture than attractiveness and increased from the first to the last session. The reasons supporting the chosen alternative increased in strength, but reasons against the non‐chosen alternative decreased. In informal comments participants reported that the study also served as a decision aid.