Unconscious memory representations in perception

Unconscious memory representations in perception: Processes and mechanisms in the brain. Ed. by István Czigler and István Winkler. (Advances in consciousness research 78.) Amsterdam: John Benjamins, 2010. Pp. x, 274. ISBN 9789027252142. $149 (Hb).

Reviewed by Svetlana Pashneva, Kursk State University

This book is an edited collection of papers focusing on the role non-conscious processes and memory representations play in perception. The book provides both a theoretical and empirical overview of the various topics of and approaches to the question in focus. A number of studies of implicit memory representations, employing various methods (e.g. psychologi­cal, neuroscience, and computational modeling) are presented. The results reviewed in this book were mostly obtained through recording event-related brain potentials (ERP) and functional magnetic resonance imaging (fMRI).

The volume consists of nine chapters, each addressing a different topic from the same approach.  Empirical evidence is evaluated in terms of its importance to models of the processes underlying conscious perception.

In ‘Conscious and unconscious aspects of working memory’ (1–35), Amanda L. Gilchrist and Nelson Cowan review the role working memory plays in conscious and non-conscious cognitive processing. The discussion of the various models of working memory is followed by the suggestion that activation-based models, particularly those that include nested processes are at an advantage in delineating conscious, preconscious, and subliminal processing. In ‘Markers of awareness? EEG potentials evoked by faint and masked events, with special reference to the “attentional blink”’ (37–70), Rolf Verleger discusses ERP components related to subjective experience and non-conscious processes. István Winkler proposes a conceptual model of auditory object formation in ‘In search for auditory object representations’ (71–106), and discusses in a common framework such important functions of the auditory system as the separation of auditory streams and auditory deviance detection. He shows that predictive sound representations exist in the human auditory system and suggests that such representations form the basis of auditory objects in the brain.

István Czigler focuses on the role sensory memory plays in au­tomatic visual change detection and perception in ‘Representation of regularities in visual stimulation: Event-related potentials reveal the automatic acquisition’ (107–31). Minna Huotilainen and Tuomas Teinonen’s chapter,‘Auditory learning in the developing brain’ (133–46), discusses the role learning and implicit memory play in perceptual development. Susan L. Denham, Salvador Dura-Bernal, Martin Coath, and Emili Balaguer-Ballester present a neurocomputational approach to model the processes underlying perceptual objects. They review models of perceptual organization in the vi­sual and auditory modalities and argue for an interpretation of perception as a process of inference. They suggest that making predictions is an effective strategy for dis­covering what’s out there, and for refining and verifying the accuracy of repre­sentations of the world.

Yury Shtyrov and Friedemann Pulvermüller in ‘Are you listening? Language outside the focus of attention’ (179–207) review and evaluate the theories of memory representations involved in speech percep­tion. They provide new insights into the non-conscious processes underlying speech perception and propose a new study paradigm. Stefan Koelsch proposes a theory of the perception of musical structure in ‘Unconscious memory representations underlying music-syntactic processing and processing of auditory oddballs’ (209–44), and emphasizes the role of non-conscious processes and implicit memory representations. Finally, in ‘On the psychophysiology of aesthetics: Automatic and controlled processes of aesthetic appreciation’ (245–57), Thomas Jacobsen reviews memory systems that operate at different levels of processing in aesthetic appreciation, demonstrating that aesthetic judgment of graphic patterns, faces, and musical cadences is preceded by the construction of information based on various memory systems operation unconsciously.

There is an appendix by Alexandra Bendixen, ‘Using electrophysiology to study unconscious memory represenations’ (259–71), which helps non-expert readers to understand the ERP method and assess the data reviewed in the various chapters of the book.