Jordan Pola - Academia.edu (original) (raw)

Papers by Jordan Pola

Research paper thumbnail of A model of perisaccadic flash mislocalization in the presence of a simple background stimulus

Journal of Vision, Aug 6, 2010

Research paper thumbnail of Visual Perception of Direction During a Saccade May Involve an Extravisual Signal that Changes as Rapidly as the Saccade

Investigative Ophthalmology & Visual Science, 2002

Research paper thumbnail of Vernier discrimination with sequentially-flashed lines: Roles of eye movements, retinal offsets and short-term memory

Vision Research, 1981

The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec d... more The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec dark interval) while the subject tried to maintain an earlier position of fixation in total darkness. Vernier discrimination deteriorates with increasing dark interval: acuity threshold increases from 29"-26'; constant error generally increases. The errors are a joint result of: (1) displacements between the retina1 images of the two lines that are not present in the target; these are produced by involuntary eye movements in the dark interval and (2) deterioration of memory for spatial location signalled by the first line flashed. The entire contribution of involuntary eye movements is due to its effect on retinal offset; extraretinal signals related to involuntary changes in eye position during the dark interval do not influence the discrimination at any dark interval. A systematic influence of eye-movement-produced retinal offset is measured even for the shortest dark interval of 0.2 msec (2.2 msec between centers of flashes). Memory

Research paper thumbnail of The perception of target motion during smooth pursuit eye movements in the open-loop condition: Characteristics of retinal and extraretinal signals

Vision Research, 1989

During smooth pursuit eye movement, the perception of target motion appears to come from retinal ... more During smooth pursuit eye movement, the perception of target motion appears to come from retinal and extraretinal influences. To explore this, two open-loop conditions (experimental stimuli stabilized at the retina) were used: one to look at the combined effect of retinal and extraretinal signals on perception (using sinusoidal target motion); and the other to look at the characteristics of an extraretinal signal alone (using a complex target and square-wave motion). In both conditions subjects tracked target motion in the dark, and subsequently compared it to motion of a similar target in the light. The main findings of the study are that the magnitude of the extraretinal signal decreases with frequency, and that the retinal and extraretinal signals combine additively. This system appears to involve a transport-time, which could be in the form of a time advance. These features of perception have a variety of implications for motor control.

Research paper thumbnail of Models of the mechanism underlying perceived location of a perisaccadic flash

Vision Research, Nov 1, 2004

A variety of experiments have shown that subjects tend to perceive a target flash as mislocalized... more A variety of experiments have shown that subjects tend to perceive a target flash as mislocalized when the flash is presented just before, during or shortly after the occurrence of a saccade. The characteristics of this mislocalization suggest that it arises from an anticipatory, slow extraretinal signal, i.e., the signal starts to change before a saccade and continues to change during and after the saccade. However, a target flash creates a visual signal that can persist for as long as 300 ms. Interaction of this visual persistence with the extraretinal signal could have a significant influence on the perceived location of the target flash, and thus on features of the extraretinal signal as inferred from the perceived location. In this study, several different types of models were used to explore how retinal signal persistence together with an extraretinal signal might affect perception. According to these models, the anticipatory, slow extraretinal signal may be an artifact of using a target flash, and the actual extraretinal signal may begin to change only after saccade onset and relatively quickly.

Research paper thumbnail of Eye movements following autokinesis

Bulletin of the psychonomic society, Nov 1, 1977

Eye movements in the dark interval following extinction of an autokinetic target are systematical... more Eye movements in the dark interval following extinction of an autokinetic target are systematically related to the direction of the target's autokinetic movement.

Research paper thumbnail of A Model of the Perceived Locations of Two Successively Flashed Targets during a Saccade

Investigative Ophthalmology & Visual Science, 2003

Research paper thumbnail of Pontomedullary reticular projections into the region of the ascending medial longitudinal fasciculus in cat

Experimental Brain Research, 1978

The medial longitudinal fasciculus (MLF) and immediately adjacent reticular formation were stimul... more The medial longitudinal fasciculus (MLF) and immediately adjacent reticular formation were stimulated electrically just caudal to the trochlear nucleus in the cat. In the pontomedullary reticular formation within 1.5 mm of the midline, antidromically excited neurons were detected in (1) the contralateral abducens nucleus, (2) the contralateral reticular formation just caudal and caudoventral to the abducens nucleus, and (3) the ipsilateral nucleus reticularis pontis caudalis beneath and rostral to the abducens nucleus. The possible involvement of these neurons in eye or body movements is discussed.

Research paper thumbnail of The intermittent light illusion and constancy of visual direction during voluntary saccades

Research paper thumbnail of Visual persistence: Effects of flash luminance, duration and energy

Research paper thumbnail of Vernier discrimination with sequentially-flashed lines: Roles of eye movements, retinal offsets and short-term memory

Vision Research, 1981

The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec d... more The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec dark interval) while the subject tried to maintain an earlier position of fixation in total darkness. Vernier discrimination deteriorates with increasing dark interval: acuity threshold increases from 29"-26'; constant error generally increases. The errors are a joint result of: (1) displacements between the retina1 images of the two lines that are not present in the target; these are produced by involuntary eye movements in the dark interval and (2) deterioration of memory for spatial location signalled by the first line flashed. The entire contribution of involuntary eye movements is due to its effect on retinal offset; extraretinal signals related to involuntary changes in eye position during the dark interval do not influence the discrimination at any dark interval. A systematic influence of eye-movement-produced retinal offset is measured even for the shortest dark interval of 0.2 msec (2.2 msec between centers of flashes). Memory

Research paper thumbnail of Visual perception of direction when voluntary saccades occur: II. Relation of visual direction of a fixation target extinguished before a saccade to a subsequent test flash presented before the saccade

Perception & Psychophysics, 1970

Research paper thumbnail of Flash and

model of the mechanism for the perceived location of a single

Research paper thumbnail of Perisaccadic flash mislocalization depends on whether a background stimulus appears or disappears around the time of the flash

Journal of Vision, 2011

... These predictions are compared with experimental results of a study with background visible j... more ... These predictions are compared with experimental results of a study with background visible just after a flash (Matin, Matin, Pola & Kowal, 1969), and the findings of a study with background disappearing at the time of a flash (Dassonville, Schlag & Schlag-Rey, 1995). ...

Research paper thumbnail of The perceived location of one flash or two successive flashes at the time of a saccade involves an extraretinal signal that begins changing at the onset of or following the saccade

Research paper thumbnail of Models of the Saccadic and Smooth Pursuit Systems

Saccadic and smooth pursuit movements are among several eye movements that we make as we visually... more Saccadic and smooth pursuit movements are among several eye movements that we make as we visually attend to objects in our environment. An important function of these two movements is to shift the direction of gaze (i.e., an imaginary line directed outward from the central fovea) to clearly view an object of interest. Both movements are concerned with the horizontal-vertical coordinates of objects. This is in contrast to vergence movements that deal with the proximal location of objects (see Chapter 11: Models of Saccadic-Vergence Interactions). A saccade is a rapid movement, perhaps the fastest of skeletal muscle movements, that quickly takes our direction of gaze from an initial point in space to some other point or target. A smooth pursuit movement is a slow to medium velocity movement that allows us to visually follow a moving target, and thus maintain our gaze on or near the target. It is generally thought that the stimulus for a saccade is target position with respect to the fovea, whereas the stimulus for smooth pursuit is target velocity relative to the retina. Saccades can occur without pursuit, and vice versa, but in many circumstances, the two types of movement act conjointly. For example, during visual following of a target moving at moderate to high velocity, smooth pursuit is typically supplemented by saccades. These saccades quickly reduce target offset from the fovea that develops when pursuit velocity is less than target velocity.

Research paper thumbnail of The Conversion of Signals in the Vestibulo-Ocular Reflex

Research paper thumbnail of Eye movements following autokinesis

Bulletin of the Psychonomic Society, 1977

Eye movements in the dark interval following extinction of an autokinetic target are systematical... more Eye movements in the dark interval following extinction of an autokinetic target are systematically related to the direction of the target's autokinetic movement.

Research paper thumbnail of Oculomotor signals in medial longitudinal fasciculus of the monkey

Journal of neurophysiology, 1978

APA PsycNET Our Apologies! - The following features are not available with your current Browser c... more APA PsycNET Our Apologies! - The following features are not available with your current Browser configuration. - alerts user that their session is about to expire - display, print, save, export, and email selected records - get My ...

Research paper thumbnail of The role of attention and cognitive processes

Reviews of oculomotor research, 1993

Research paper thumbnail of A model of perisaccadic flash mislocalization in the presence of a simple background stimulus

Journal of Vision, Aug 6, 2010

Research paper thumbnail of Visual Perception of Direction During a Saccade May Involve an Extravisual Signal that Changes as Rapidly as the Saccade

Investigative Ophthalmology & Visual Science, 2002

Research paper thumbnail of Vernier discrimination with sequentially-flashed lines: Roles of eye movements, retinal offsets and short-term memory

Vision Research, 1981

The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec d... more The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec dark interval) while the subject tried to maintain an earlier position of fixation in total darkness. Vernier discrimination deteriorates with increasing dark interval: acuity threshold increases from 29"-26'; constant error generally increases. The errors are a joint result of: (1) displacements between the retina1 images of the two lines that are not present in the target; these are produced by involuntary eye movements in the dark interval and (2) deterioration of memory for spatial location signalled by the first line flashed. The entire contribution of involuntary eye movements is due to its effect on retinal offset; extraretinal signals related to involuntary changes in eye position during the dark interval do not influence the discrimination at any dark interval. A systematic influence of eye-movement-produced retinal offset is measured even for the shortest dark interval of 0.2 msec (2.2 msec between centers of flashes). Memory

Research paper thumbnail of The perception of target motion during smooth pursuit eye movements in the open-loop condition: Characteristics of retinal and extraretinal signals

Vision Research, 1989

During smooth pursuit eye movement, the perception of target motion appears to come from retinal ... more During smooth pursuit eye movement, the perception of target motion appears to come from retinal and extraretinal influences. To explore this, two open-loop conditions (experimental stimuli stabilized at the retina) were used: one to look at the combined effect of retinal and extraretinal signals on perception (using sinusoidal target motion); and the other to look at the characteristics of an extraretinal signal alone (using a complex target and square-wave motion). In both conditions subjects tracked target motion in the dark, and subsequently compared it to motion of a similar target in the light. The main findings of the study are that the magnitude of the extraretinal signal decreases with frequency, and that the retinal and extraretinal signals combine additively. This system appears to involve a transport-time, which could be in the form of a time advance. These features of perception have a variety of implications for motor control.

Research paper thumbnail of Models of the mechanism underlying perceived location of a perisaccadic flash

Vision Research, Nov 1, 2004

A variety of experiments have shown that subjects tend to perceive a target flash as mislocalized... more A variety of experiments have shown that subjects tend to perceive a target flash as mislocalized when the flash is presented just before, during or shortly after the occurrence of a saccade. The characteristics of this mislocalization suggest that it arises from an anticipatory, slow extraretinal signal, i.e., the signal starts to change before a saccade and continues to change during and after the saccade. However, a target flash creates a visual signal that can persist for as long as 300 ms. Interaction of this visual persistence with the extraretinal signal could have a significant influence on the perceived location of the target flash, and thus on features of the extraretinal signal as inferred from the perceived location. In this study, several different types of models were used to explore how retinal signal persistence together with an extraretinal signal might affect perception. According to these models, the anticipatory, slow extraretinal signal may be an artifact of using a target flash, and the actual extraretinal signal may begin to change only after saccade onset and relatively quickly.

Research paper thumbnail of Eye movements following autokinesis

Bulletin of the psychonomic society, Nov 1, 1977

Eye movements in the dark interval following extinction of an autokinetic target are systematical... more Eye movements in the dark interval following extinction of an autokinetic target are systematically related to the direction of the target's autokinetic movement.

Research paper thumbnail of A Model of the Perceived Locations of Two Successively Flashed Targets during a Saccade

Investigative Ophthalmology & Visual Science, 2003

Research paper thumbnail of Pontomedullary reticular projections into the region of the ascending medial longitudinal fasciculus in cat

Experimental Brain Research, 1978

The medial longitudinal fasciculus (MLF) and immediately adjacent reticular formation were stimul... more The medial longitudinal fasciculus (MLF) and immediately adjacent reticular formation were stimulated electrically just caudal to the trochlear nucleus in the cat. In the pontomedullary reticular formation within 1.5 mm of the midline, antidromically excited neurons were detected in (1) the contralateral abducens nucleus, (2) the contralateral reticular formation just caudal and caudoventral to the abducens nucleus, and (3) the ipsilateral nucleus reticularis pontis caudalis beneath and rostral to the abducens nucleus. The possible involvement of these neurons in eye or body movements is discussed.

Research paper thumbnail of The intermittent light illusion and constancy of visual direction during voluntary saccades

Research paper thumbnail of Visual persistence: Effects of flash luminance, duration and energy

Research paper thumbnail of Vernier discrimination with sequentially-flashed lines: Roles of eye movements, retinal offsets and short-term memory

Vision Research, 1981

The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec d... more The two lines of a vertical vernier target were sequentially flashed (2 msec/line; 0.2-800 msec dark interval) while the subject tried to maintain an earlier position of fixation in total darkness. Vernier discrimination deteriorates with increasing dark interval: acuity threshold increases from 29"-26'; constant error generally increases. The errors are a joint result of: (1) displacements between the retina1 images of the two lines that are not present in the target; these are produced by involuntary eye movements in the dark interval and (2) deterioration of memory for spatial location signalled by the first line flashed. The entire contribution of involuntary eye movements is due to its effect on retinal offset; extraretinal signals related to involuntary changes in eye position during the dark interval do not influence the discrimination at any dark interval. A systematic influence of eye-movement-produced retinal offset is measured even for the shortest dark interval of 0.2 msec (2.2 msec between centers of flashes). Memory

Research paper thumbnail of Visual perception of direction when voluntary saccades occur: II. Relation of visual direction of a fixation target extinguished before a saccade to a subsequent test flash presented before the saccade

Perception & Psychophysics, 1970

Research paper thumbnail of Flash and

model of the mechanism for the perceived location of a single

Research paper thumbnail of Perisaccadic flash mislocalization depends on whether a background stimulus appears or disappears around the time of the flash

Journal of Vision, 2011

... These predictions are compared with experimental results of a study with background visible j... more ... These predictions are compared with experimental results of a study with background visible just after a flash (Matin, Matin, Pola & Kowal, 1969), and the findings of a study with background disappearing at the time of a flash (Dassonville, Schlag & Schlag-Rey, 1995). ...

Research paper thumbnail of The perceived location of one flash or two successive flashes at the time of a saccade involves an extraretinal signal that begins changing at the onset of or following the saccade

Research paper thumbnail of Models of the Saccadic and Smooth Pursuit Systems

Saccadic and smooth pursuit movements are among several eye movements that we make as we visually... more Saccadic and smooth pursuit movements are among several eye movements that we make as we visually attend to objects in our environment. An important function of these two movements is to shift the direction of gaze (i.e., an imaginary line directed outward from the central fovea) to clearly view an object of interest. Both movements are concerned with the horizontal-vertical coordinates of objects. This is in contrast to vergence movements that deal with the proximal location of objects (see Chapter 11: Models of Saccadic-Vergence Interactions). A saccade is a rapid movement, perhaps the fastest of skeletal muscle movements, that quickly takes our direction of gaze from an initial point in space to some other point or target. A smooth pursuit movement is a slow to medium velocity movement that allows us to visually follow a moving target, and thus maintain our gaze on or near the target. It is generally thought that the stimulus for a saccade is target position with respect to the fovea, whereas the stimulus for smooth pursuit is target velocity relative to the retina. Saccades can occur without pursuit, and vice versa, but in many circumstances, the two types of movement act conjointly. For example, during visual following of a target moving at moderate to high velocity, smooth pursuit is typically supplemented by saccades. These saccades quickly reduce target offset from the fovea that develops when pursuit velocity is less than target velocity.

Research paper thumbnail of The Conversion of Signals in the Vestibulo-Ocular Reflex

Research paper thumbnail of Eye movements following autokinesis

Bulletin of the Psychonomic Society, 1977

Eye movements in the dark interval following extinction of an autokinetic target are systematical... more Eye movements in the dark interval following extinction of an autokinetic target are systematically related to the direction of the target's autokinetic movement.

Research paper thumbnail of Oculomotor signals in medial longitudinal fasciculus of the monkey

Journal of neurophysiology, 1978

APA PsycNET Our Apologies! - The following features are not available with your current Browser c... more APA PsycNET Our Apologies! - The following features are not available with your current Browser configuration. - alerts user that their session is about to expire - display, print, save, export, and email selected records - get My ...

Research paper thumbnail of The role of attention and cognitive processes

Reviews of oculomotor research, 1993