A short history of the study of the interAction between oculomotor control And shifts of visuAl Attention

The study of the neural mechanisms underlying visual attention has been bound up with the study of oculomotor control for almost as long as both have been investigated scientifically. Before the 1970s, most knowledge about the neural mechanisms of visual attention and oculomotor control was derived from lesion studies in animals and from clinical case reports. The phenomenon of contralateral inattention following posterior parietal lobe injury in humans was well documented, but it did not seem possible to approach the study of the neural substrates of visual attention directly, given the technological limitations of the time. However, in the early 1970s, several laboratories began the study of the activity of single neurons in monkeys that were alert and performing learned behavioral tasks, including tasks involving voluntary eye movements and involving shifts of visual attention. A group at Johns Hopkins proposed that 43 oculomotor control and shifts of Visual attention some neurons in posterior parietal cortex participated in the initiation and control of visually-guided saccadic eye movements and visual pursuit movements, while another group argued that all neural activity in the posterior parietal lobe was related to visual attention rather than oculomotor control, and that only the frontal eye field, located in prefrontal association cortex, participated in active oculomotor control. From this difference of interpretation grew more than thirty years of active investigation and discussion that has involved many different laboratories as they worked toward further understanding of the neural circuitry underlying visual attention and oculomotor control. Neurophysiological, neuroanatomical, and functional imaging studies have led to the present concept of cortico-cortical networks which incorporate nodes that play a role in both oculomotor and visual attention functions. In fact, recent research results suggest that the functions of visual attention and oculomotor control may be inextricably linked with one another perhaps two sides of the same coin. The present paper is intended to be a brief historical overview of the development of some of the current concepts of the interaction between the neural mechanisms of attention and those of oculomotor control.