Dr. David Anaki, a Lecturer in the Department of Psychology and in the Gonda Multidisciplinary Brain Research Center, studies the psychological, neuropsychological, and neural properties of the human visual system. Anaki and his team investigate the unique mechanisms and processes that underlie the perception of various visual categories such as faces, objects, scenes and words, as well as the commonalities between them.
These issues are investigated by combining electrophysiological (ERP) and behavioral techniques, and by examining healthy individuals as well as individuals with specific neuropsychological deficits that affect various aspects of visual perception, such as agnosia, prosopagnosia, simultanagnosia and posterior cerebral atrophy (PCA).
One basic process that is inherent in visual perception is temporal integration, namely, the ability to form a unified representation from temporally-separated stimuli.
Anaki and his group probe the memory systems that enable this process, the characteristics of the integration process, and the features of the visual representations that are formed. Thus, for example, they have shown that face parts can be integrated to form a holistic representation within a temporal window of approximately half a second. However, if the interval between the parts is longer, the face parts are processed independently and are not integrated.
Research conducted in Anaki’s lab explores the role of spatial attention in visual perception, both in a general sense and particularly in face perception. Recently, they have shown that face perception can be characterized by both automatic and non-automatic aspects. For example, holistic face perception is an obligatory process, which means that when presented with a face, a perceiver cannot focus on one facial feature and ignore its other features.
On the other hand, their findings also demonstrate that spatial attention is required in order for faces to be holistically perceived. Anaki and his team are currently working on several studies that will help clarify the interaction between attention and face perception.
Anaki and his team are also studying the mechanisms underlying various neurodegenerative diseases. They examine how progressive atrophy of the posterior part of the brain affects visual tasks such as reading and identifying faces. In another project, Anaki and his group are using statistical methods to assess individuals suffering from mild cognitive impairment in order to determine whether their difficulties constitute a precursor of Alzheimer’s disease.
In their future endeavors, Anaki and his team aim to provide a more complete picture of how visual perception and cognitive processes work together in face perception. In addition, they hope to venture into the social and emotional aspects involved in face perception.