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You can find similar aftereffects when you stare out the front window of a moving vehicle for a couple of minutes and then stop: the landscape suddenly seems to slowly move away from you for some time; or when you stare out the widow of a train: when it stops the landscape appears to slowly move in the opposite direction. Aftereffects of this type can have any direction: when you stare at a rotating image and the rotation stops, the image appears to rotate in the opposite direction. Depending on the stimulus, this can be a smooth motion or it "jumps" forward and back.

This is called the direction aftereffect (DAE), "whereby prolonged exposure to a moving pattern affects the perceived direction of subsequent motion" (Clifford, 2002). This is an effect of perceptual adaptation, where the brain compensates for a supposed error in perception.

The mechanism behind this phenomenon was tested by Schrater and SmoncelliSimoncelli (1998):

Adaptation to a moving visual pattern induces shifts in the perceived motion of subsequently viewed moving patterns. Explanations of such effects are typically based on adaptation-induced sensitivity changes in spatio-temporal frequency tuned mechanisms (STFMs). An alternative hypothesis is that adaptation occurs in mechanisms that independently encode direction and speed (DSMs). Yet a third possibility is that adaptation occurrs in mechanisms that encode 2D pattern velocity (VMs). We performed a series of psychophysical experiments to examine predictions made by each of the three hypotheses. The results indicate that: (1) adaptation-induced shifts are relatively independent of spatial pattern of both adapting and test stimuli; (2) the shift in perceived direction of motion of a plaid stimulus after adaptation to a grating indicates a shift in the motion of the plaid pattern, and not a shift in the motion of the plaid components; and (3) the 2D pattern of shift in perceived velocity radiates away from the adaptation velocity, and is inseparable in speed and direction of motion. Taken together, these results are most consistent with the VM adaptation hypothesis.

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You can find similar aftereffects when you stare out the front window of a moving vehicle for a couple of minutes and then stop: the landscape suddenly seems to slowly move away from you for some time; or when you stare out the widow of a train: when it stops the landscape appears to slowly move in the opposite direction. Aftereffects of this type can have any direction: when you stare at a rotating image and the rotation stops, the image appears to rotate in the opposite direction. Depending on the stimulus, this can be a smooth motion or it "jumps" forward and back.

This is called the direction aftereffect (DAE), "whereby prolonged exposure to a moving pattern affects the perceived direction of subsequent motion" (Clifford, 2002). This is an effect of perceptual adaptation, where the brain compensates for a supposed error in perception.

The mechanism behind this phenomenon was tested by Schrater and Smoncelli (1998):

Adaptation to a moving visual pattern induces shifts in the perceived motion of subsequently viewed moving patterns. Explanations of such effects are typically based on adaptation-induced sensitivity changes in spatio-temporal frequency tuned mechanisms (STFMs). An alternative hypothesis is that adaptation occurs in mechanisms that independently encode direction and speed (DSMs). Yet a third possibility is that adaptation occurrs in mechanisms that encode 2D pattern velocity (VMs). We performed a series of psychophysical experiments to examine predictions made by each of the three hypotheses. The results indicate that: (1) adaptation-induced shifts are relatively independent of spatial pattern of both adapting and test stimuli; (2) the shift in perceived direction of motion of a plaid stimulus after adaptation to a grating indicates a shift in the motion of the plaid pattern, and not a shift in the motion of the plaid components; and (3) the 2D pattern of shift in perceived velocity radiates away from the adaptation velocity, and is inseparable in speed and direction of motion. Taken together, these results are most consistent with the VM adaptation hypothesis.

Sources:

You can find similar aftereffects when you stare out the front window of a moving vehicle for a couple of minutes and then stop: the landscape suddenly seems to slowly move away from you for some time; or when you stare out the widow of a train: when it stops the landscape appears to slowly move in the opposite direction. Aftereffects of this type can have any direction: when you stare at a rotating image and the rotation stops, the image appears to rotate in the opposite direction. Depending on the stimulus, this can be a smooth motion or it "jumps" forward and back.

This is called the direction aftereffect (DAE), "whereby prolonged exposure to a moving pattern affects the perceived direction of subsequent motion" (Clifford, 2002). This is an effect of perceptual adaptation, where the brain compensates for a supposed error in perception.

The mechanism behind this phenomenon was tested by Schrater and Simoncelli (1998):

Adaptation to a moving visual pattern induces shifts in the perceived motion of subsequently viewed moving patterns. Explanations of such effects are typically based on adaptation-induced sensitivity changes in spatio-temporal frequency tuned mechanisms (STFMs). An alternative hypothesis is that adaptation occurs in mechanisms that independently encode direction and speed (DSMs). Yet a third possibility is that adaptation occurrs in mechanisms that encode 2D pattern velocity (VMs). We performed a series of psychophysical experiments to examine predictions made by each of the three hypotheses. The results indicate that: (1) adaptation-induced shifts are relatively independent of spatial pattern of both adapting and test stimuli; (2) the shift in perceived direction of motion of a plaid stimulus after adaptation to a grating indicates a shift in the motion of the plaid pattern, and not a shift in the motion of the plaid components; and (3) the 2D pattern of shift in perceived velocity radiates away from the adaptation velocity, and is inseparable in speed and direction of motion. Taken together, these results are most consistent with the VM adaptation hypothesis.

Sources:

Source Link
user3116
user3116

You can find similar aftereffects when you stare out the front window of a moving vehicle for a couple of minutes and then stop: the landscape suddenly seems to slowly move away from you for some time; or when you stare out the widow of a train: when it stops the landscape appears to slowly move in the opposite direction. Aftereffects of this type can have any direction: when you stare at a rotating image and the rotation stops, the image appears to rotate in the opposite direction. Depending on the stimulus, this can be a smooth motion or it "jumps" forward and back.

This is called the direction aftereffect (DAE), "whereby prolonged exposure to a moving pattern affects the perceived direction of subsequent motion" (Clifford, 2002). This is an effect of perceptual adaptation, where the brain compensates for a supposed error in perception.

The mechanism behind this phenomenon was tested by Schrater and Smoncelli (1998):

Adaptation to a moving visual pattern induces shifts in the perceived motion of subsequently viewed moving patterns. Explanations of such effects are typically based on adaptation-induced sensitivity changes in spatio-temporal frequency tuned mechanisms (STFMs). An alternative hypothesis is that adaptation occurs in mechanisms that independently encode direction and speed (DSMs). Yet a third possibility is that adaptation occurrs in mechanisms that encode 2D pattern velocity (VMs). We performed a series of psychophysical experiments to examine predictions made by each of the three hypotheses. The results indicate that: (1) adaptation-induced shifts are relatively independent of spatial pattern of both adapting and test stimuli; (2) the shift in perceived direction of motion of a plaid stimulus after adaptation to a grating indicates a shift in the motion of the plaid pattern, and not a shift in the motion of the plaid components; and (3) the 2D pattern of shift in perceived velocity radiates away from the adaptation velocity, and is inseparable in speed and direction of motion. Taken together, these results are most consistent with the VM adaptation hypothesis.

Sources: