Brian F. O'Donnell, Dean F. Salisbury, Margaret A. Niznikiewicz, Colleen A. Brenner, and Jenifer L. Vohs
Schizophrenia is a disabling psychotic illness that has been associated with alterations in synaptic connectivity and neurotransmission. Since event-related potential (ERP) components are typically generated by the summation of postsynaptic potentials produced by neural populations, these measures are well suited to assess such pathophysiological alterations. This chapter reviews the utility of ERP components in the investigation of the cognitive and neural mechanisms affected by schizophrenia. It focuses on five components: mismatch negativity (MMN), P50 measures of sensory gating, N100 and P300 in the oddball discrimination paradigms, and the N400 component elicited during language processing. These components test key cognitive systems affected by schizophrenia: sensory memory (MMN), sensory processing and inhibition (P50, N1), selective attention and working memory (P300), and semantic processing (N400). These components are discussed with respect to the following issues: (1) cognitive and neural systems indexed by the component, (2) abnormalities in schizophrenia, (3) sensitivity and specificity to schizophrenia, (4) clinical correlates, and (5) relationship to genetic variation. ERP components are well validated biomarkers for schizophrenia which have significant promise in the characterization of genomic and epigenomic factors, pharmacological response in humans and animal models, and the developmental and cognitive expression of the illness.
Absolute pitch (AP) is the ability to identify or categorize musical pitches accurately without an external reference. Although AP is generally thought to be rare, music psychology research in the past few decades has debated on every aspect of the phenomenon. This chapter will review the theories, methods, and findings on AP from the cognitive psychology and neuroscience literature, with the goal of elucidating some of the following controversies on AP: its identification and prevalence, its genetic and environmental origins, its psychological and neural underpinnings, and the degree to which it may be informative as a scientific model of brain function.
The chapter illustrates the historical background, the theoretical ideas, and the empirical findings that make achromatic transparency a central phenomenon in perceptual organization research. Perceived transparency is a case of double-belongingness, consistent with the tendency to minimize the complexity of visual organization at the levels of both form and color. Conditions and effects of achromatic transparency are reviewed, in the perspective of percept-percept coupling. Topological, figural, and photometric conditions are described, taking the episcotister as the reference physical model and the availability of X-junctions in a four-region pattern as the typical image information. Achromatic transparency is also discussed in the context of other layering effects (cast shadows, lightness of opaque surfaces, illumination) and in relation to constancy, depth, and motion.
William J. Davies
This article provides an overview of what shapes the acoustic signals that arrive at the ear. There are three physical processes which are capable of generating audible sound: a vibrating surface, a turbulent fluid, and a rapid pressure change. It is structured as an account of the journey of a sound wave, from first generation, then propagation outdoors, followed by transmission into a building and indoor reverberation to its final reception, perception, and assessment. It throws light on how the signals that arrive at the ear are generated; how environment influences these signals; and how sound is perceived, controlled, and assessed in the environment. It gives information on basic principles, common measurements and current modelling techniques. Finally, it suggests that the external environment is complex and the acoustic signals arriving the ear reflect this complexity by carrying information about their production, their interaction with the environment, and their transmission through it.
Ellyn A. Riley, C. Elizabeth Brookshire, and Diane L. Kendall
Reading is one of the most important cognitive skills an individual can acquire and the process of reading has been debated much in the psycholinguistic, neurolinguistic, and educational literature for many years now. Much of this literature has discussed the process of reading, proposed theoretical models to describe its components, and identification of neuroanatomic underpinnings. In this chapter we have attempted to provide a review of both dual-route and connectionist models of alexia, outline specific types of peripheral and central alexias, provide a brief overview of the neural substrates linked with reading processes, and finally offer diagnostic and treatment strategies.
Pélagie M. Beeson and Kindle Rising
Acquired dysgraphia refers to disorders of spelling or writing due to neurological damage in individuals with normal premorbid literacy skills. Dysgraphia can result from the disruption of central cognitive processes that also support spoken language and reading, so that spelling impairments frequently co-occur with aphasia and acquired alexia. The ability to produce written words can also be affected by damage to peripheral processes necessary to plan and execute the appropriate hand movements for letter generation or typing. In this chapter, we review the cognitive processes that support spelling and writing, and the characteristic dysgraphia syndromes that reflect differential impairment to specific central and peripheral components. We also review assessment procedures for writing and spelling that are structured to clarify the status of component processes and to guide rehabilitation planning. Treatment procedures and sequences are described with a focus on lexical-semantic, phonological, and interactive treatments. The nature and treatment of dysgraphia are illustrated by case examples of global dysgraphia, phonological dysgraphia, and surface dysgraphia.
Benjamin Margolin Rottman
This chapter provides an introduction to how humans learn and reason about multiple causal relations connected together in a causal structure. The first half of the chapter focuses on how people learn causal structures. The main topics involve learning from observations versus interventions, learning temporal versus atemporal causal structures, and learning the parameters of a causal structure including individual cause-effect strengths and how multiple causes combine to produce an effect. The second half of the chapter focuses on how individuals reason about the causal structure, such as making predictions about one variable given knowledge about other variables, once the structure has been learned. Some of the most important topics involve reasoning about observations versus interventions, how well people reason compared to normative models, and whether causal structure beliefs bias reasoning. In both sections the author highlights open empirical and theoretical questions.
Deborah Chen Pichler and Elena Koulidobrova
Research interest in sign L21 sign acquisition is growing, fueled by dramatic increases in sign language learning (Welles, 2004). Researchers ask to what extent typical L2 patterns apply to hearing students learning an L2 in a new modality, or M2 (second modality)-L2 learners. M2 acquisition may pose unique challenges not observed in typical (unimodal) L2 acquisition. At the same time, co-speech gestures and emblems could potentially be exploited to facilitate M2-L2 acquisition of sign language. Additionally, examination of acquisition of a second signed language by individuals with a signed L1, or M1 (first modality)-L2 learners, provides further opportunity to test “typical” patterns of L2 acquisition that have been established almost exclusively on the basis of hearing spoken second-language acquisition. This chapter summarizes the small but growing literature on L2 sign acquisition for both M1 and M2 learners, exploring some of the intriguing research questions offered by L2 sign research.
Dario D. Salvucci
ACT-R is a computational cognitive architecture intended to represent and simulate human thoughts and behaviors. It posits a declarative knowledge base with an associated computational account of memory recall and decay, and a procedural knowledge base with condition-action production rules representing procedural skill in performing task actions. By developing computational models using ACT-R, researchers can more rigorously explore the workings of the mind by predicting cognitive, perceptual, and motor behavior, and by comparing this behavior quantitatively to human behavior in the same tasks. ACT-R can also be used to generate quantitative predictions of behavior (e.g., on a human-computer interface) and infer a person’s underlying cognitive state for the duration of a task. ACT-R has played a central role in many research and applied efforts and now serves as a central repository of cognitive theory to which a community of cognitive researchers can contribute and from which they can benefit.