Perception Adaptation Lab Report
The Effects of Disrupted Visual Fields on Perception:
Perception Adaptation
Submitted in Partial Fulfillment of requirements for Psychology 1100E
Abstract
Kornheiser and Stratton are responsible for much of the modern day understanding of perception and adaptation. The purpose of this experiment was to examine the affects of sensory changes on perception adaptation. In this particular experiment, 105 Huron University College students completed a simple task. At a certain point the participants had their visual field displaced 11.5 degrees to the right by glasses and then some participants did the task 10 times and others did it three times. They repeated the task again once the glasses had been removed …show more content…
the task was repeated and the results of the two groups were then analyzed. The results suggested that there was little difference in the ability to perform the task between the two groups, which did not support the hypothesis that longer time spent with a displaced visual field would yield stronger effects once the glasses were removed.
Perception is an age old concept distrusted by enlightenment philosopher Plato. However, many others had faith in perception which they believed to be based on experience gained as a child. Depth perception in particular was believed by Berkeley to come from touching objects and seeing many things at a range of distances as a child. Gregory and Wallace conducted an experiment in which a patient regained sight at the age of 50. In the beginning, the patient couldn’t differentiate between visual images however over time the patient developed normal depth perception, this backed up the beliefs that Berkeley had that visual perception was developed by experience and not maturation. …show more content…
Experiments conducted by Stratton in 1896, hoped to prove that changing a visual field could lead to adaptation and that the disrupted vision field would appear normal. His experiment taught him that he was able to quickly adapt to his new vision. Kornheiser came up with a few terms to describe the process of adaptation: Adaptation Phase - when the visual field is disrupted or changed. Aftereffect Phase - the time period after the vision has been disrupted and the entire experience is called Perceptual Adaptation. Participants’ hand -eye coordination is then tested without a disrupted field of vision, then alternating back and forth between a disrupted and not disrupted field. Most participants had a similar result, they were more accurate in hand eye coordination tasks during the aftereffect phase than they were during the adaptation phase, which concurs with Stratton’s original hypothesis. Kornheiser talks about theories of what people adapt to during adaptation phase and how they must readjust in the aftereffect phase: Proprioception Change: This theory says that what the changes is the position sense of the arm. The feeling of where the arm is in space without the need to see is proprioception. So when the vision field is shifted, the arm goes into adaptation to get used to reaching/pointing to things that have appeared to have moved. Efferent Change: This theory says that what changed are the efferent commands given to the arm. It suggests that the participant changes the way the motor cortex sends efferent commands to the arm. Central Change: Argues that perception changes. This means that the patient would be viewing the change as normal. If the patient were to point straight ahead (according to them) both the target and arm would actually be left or right depending on the glasses. Proprioceptive Change is the most commonly accepted theory as a result of experiments done by Harris, whose work with prisms uncovered findings, which agreed with Proprioceptive and Efferent Change. In this experiment it is being hypothesized that the participants who have to do a task 10 time in the adaptation phase will have stronger effects in the after effect stage as apposed the participants who perform the task three times.
Method
Participants From 105 Huron University College students, 50 were randomly selected for this study. There were both males and females, with a large majority being in their late teens to early twenties. The participants were selected from the Psychology 1100E lab sections.
Materials The experiment was conducted in the V107 Lab, there was a desk, which was approximately 120 cm in length, which was used to keep the participant at a consistent distance from the wall. On the wall hung a white felt board, 60 cm in width and 40 cm in length. Down the middle of this board runs a vertical Velcro line 5 cm in width. Two ping pong balls are covered in Velcro strips. Three recording sheets were handed out to the participants. Glasses from The Bernell Corporation, these glasses had lenses designed to displace vision 11.5 degrees to the right. The final material included were cleaning the supplies for the glasses such as alcohol solution and paper towels.
Procedure
To begin the experiment participants had to sign a consent form. Next they sorted themselves into groups of three and found a target board. The participants were divided into two groups, if they had an even birthday they were put into the “3 Group” which got three throws during the adaptation phase. If they were born on an odd day then they were placed into the “10 Group” which got 10 throws during the adaptation phase. Amongst the three participants the jobs of Participant, Experimenter and Data Recorder were divvied up. The experiment began when the Participants legs were touching the table. At this time the Experimenter told them to throw and the Data Recorder kept track of whether the throw was a hit or miss. A hit is defined as when the Velcro covered ping pong ball stuck to the black strip or there was no visible white felt in between the ball and target line. A miss is when the ball does not come intact with the black target line. The Participant was not to move away from the table and after each throw the Experimenter retrieved the ball for the Participant. The Participant continued to throw until they got five “hits” in a row. At this time the vision displacement goggles were put on the Participant to shift their vision 11.5 degrees to the right. Then the Participant would throw again, either three or 10 times depending on if they were in the “3 Group” or “10 Group”, the time that the Participant had the glasses on is referred to as the Adaptation Phase. During the Adaptation Phase the trials were conducted in the same manner as before, with the Data Recorder keeping track of the “hits” or “misses” and the Experimenter handing the ball to the Participant and declaring either a “hit” or “miss”. The next step is for the Participant to remove the goggles and begin the After Effect Stage in which they continue to throw until the get five consecutive “hits” as declared by the Experimenter who is still handing them the ball and the Data Recorder writing down the results. Each member of the group gets a turn in each role until all have done each job once. At this time the experiment is finished.
Results
From a sample of 105 participants, 50 were randomly selected. Of these fifty, 25 were from the “3 Group” and 25 were from the “10 Group”. The average number of throws required by the “3 Group” to gets five successive “hits” during the After Effect Phase was 17.64 and the average number of throws taken by the participants in the “10 Group” to get five “hits” in a row was 20.92. A t-test proved that there was no significant difference between the amount of throws required by the “3 Group” and “10 Group” to hit the target five times in a row (t(48)=0.2, p > 0.05). Since the calculated t value was 0.2 this means that a null hypothesis can be accepted.
Discussion
The hypothesis of this experiment was that the “10 Group” would have more substantial after effects as apposed to the “3 Group”.
This calculated results determined that there was very minor relation between the amount of time spent in the adaptation phase and how substantial the effects would be in the after effect stage. “As proven by the experiment, there was very little difference between the two groups. Experiments conducted by Stratton in 1896 suggested that the longer a person had to adjust to a visual field the more accurate their proprioceptive senses would be. “when visual and position senses are in conflict, people learn to adjust the sense of where parts of their body are so that visual and position sense no longer disagree” (Cole, 2013). If the visual field were to be interfered with (as it was with the goggles) the proprioceptive senses would adjust to fit the circumstances. However, the results obtained from the experiment conducted would
disagree. There were many methodological issues that may have skewed the results of this experiment. Had the experiment be conducted in a much more controlled and monitored environment the results could have been more accurate. Several factors may have been involved in sewing the data, such as the demographic. With the majority of participants being in their late teens to early twenties this does not best represent a universal population. Secondly, this experiment was does done primarily with first year university students who, for the most part, were unfamiliar with their classmates. The added pressure of trying to impress their peers could have acted as a factor. To solve these problems the participant could perform the task in a room by themselves so as to eliminate any social anxieties as well as to create a substantially more controlled and monitored environment. Mechanical problems were also an issue in this experiment. If the Velcro on the ball did not stick to the Velcro target than it was up to experimenter to use their best judgment as to whether or not the ball hit the target. Secondly, the target board would tend to sway during the experiment, which increased the difficulty. Having a touch sensitive board that could one hundred percent guarantee a “hit” or “miss” that was also locked into position would solve both of these problems. A potential reason for the unsubstantial difference in results between to the groups may have been caused by the minor difference in time spent during the adaptation phase. In future experiments, there should be a significant time difference in the adaptation phase. The “3 Group” could still have three throws but perhaps give the “10 Group” one hundred, this would give the “10 Group” more time to adapt and theoretically give a stronger effect in the after effect stage. The results of this experiment do not concur with the earlier stated hypothesis. Research in this area of psychology goes a long way back but there is still much more to be explored. Gaining a better understanding of how the afferent and efferent changes work together with one another could lead to many incredible discoveries. For example, developing prosthetic limbs for amputees could take an incredible leap forward if a greater knowledge of this area in psychology were had. The benefits of the brain to adapt to information it is receiving from the senses is immeasurable.
References
Cole, M.R. (2013). Perceptual Adaptation
Perception Adaptation
Submitted in Partial Fulfillment of requirements for Psychology 1100E
Abstract
Kornheiser and Stratton are responsible for much of the modern day understanding of perception and adaptation. The purpose of this experiment was to examine the affects of sensory changes on perception adaptation. In this particular experiment, 105 Huron University College students completed a simple task. At a certain point the participants had their visual field displaced 11.5 degrees to the right by glasses and then some participants did the task 10 times and others did it three times. They repeated the task again once the glasses had been removed …show more content…
the task was repeated and the results of the two groups were then analyzed. The results suggested that there was little difference in the ability to perform the task between the two groups, which did not support the hypothesis that longer time spent with a displaced visual field would yield stronger effects once the glasses were removed.
Perception is an age old concept distrusted by enlightenment philosopher Plato. However, many others had faith in perception which they believed to be based on experience gained as a child. Depth perception in particular was believed by Berkeley to come from touching objects and seeing many things at a range of distances as a child. Gregory and Wallace conducted an experiment in which a patient regained sight at the age of 50. In the beginning, the patient couldn’t differentiate between visual images however over time the patient developed normal depth perception, this backed up the beliefs that Berkeley had that visual perception was developed by experience and not maturation. …show more content…
Experiments conducted by Stratton in 1896, hoped to prove that changing a visual field could lead to adaptation and that the disrupted vision field would appear normal. His experiment taught him that he was able to quickly adapt to his new vision. Kornheiser came up with a few terms to describe the process of adaptation: Adaptation Phase - when the visual field is disrupted or changed. Aftereffect Phase - the time period after the vision has been disrupted and the entire experience is called Perceptual Adaptation. Participants’ hand -eye coordination is then tested without a disrupted field of vision, then alternating back and forth between a disrupted and not disrupted field. Most participants had a similar result, they were more accurate in hand eye coordination tasks during the aftereffect phase than they were during the adaptation phase, which concurs with Stratton’s original hypothesis. Kornheiser talks about theories of what people adapt to during adaptation phase and how they must readjust in the aftereffect phase: Proprioception Change: This theory says that what the changes is the position sense of the arm. The feeling of where the arm is in space without the need to see is proprioception. So when the vision field is shifted, the arm goes into adaptation to get used to reaching/pointing to things that have appeared to have moved. Efferent Change: This theory says that what changed are the efferent commands given to the arm. It suggests that the participant changes the way the motor cortex sends efferent commands to the arm. Central Change: Argues that perception changes. This means that the patient would be viewing the change as normal. If the patient were to point straight ahead (according to them) both the target and arm would actually be left or right depending on the glasses. Proprioceptive Change is the most commonly accepted theory as a result of experiments done by Harris, whose work with prisms uncovered findings, which agreed with Proprioceptive and Efferent Change. In this experiment it is being hypothesized that the participants who have to do a task 10 time in the adaptation phase will have stronger effects in the after effect stage as apposed the participants who perform the task three times.
Method
Participants From 105 Huron University College students, 50 were randomly selected for this study. There were both males and females, with a large majority being in their late teens to early twenties. The participants were selected from the Psychology 1100E lab sections.
Materials The experiment was conducted in the V107 Lab, there was a desk, which was approximately 120 cm in length, which was used to keep the participant at a consistent distance from the wall. On the wall hung a white felt board, 60 cm in width and 40 cm in length. Down the middle of this board runs a vertical Velcro line 5 cm in width. Two ping pong balls are covered in Velcro strips. Three recording sheets were handed out to the participants. Glasses from The Bernell Corporation, these glasses had lenses designed to displace vision 11.5 degrees to the right. The final material included were cleaning the supplies for the glasses such as alcohol solution and paper towels.
Procedure
To begin the experiment participants had to sign a consent form. Next they sorted themselves into groups of three and found a target board. The participants were divided into two groups, if they had an even birthday they were put into the “3 Group” which got three throws during the adaptation phase. If they were born on an odd day then they were placed into the “10 Group” which got 10 throws during the adaptation phase. Amongst the three participants the jobs of Participant, Experimenter and Data Recorder were divvied up. The experiment began when the Participants legs were touching the table. At this time the Experimenter told them to throw and the Data Recorder kept track of whether the throw was a hit or miss. A hit is defined as when the Velcro covered ping pong ball stuck to the black strip or there was no visible white felt in between the ball and target line. A miss is when the ball does not come intact with the black target line. The Participant was not to move away from the table and after each throw the Experimenter retrieved the ball for the Participant. The Participant continued to throw until they got five “hits” in a row. At this time the vision displacement goggles were put on the Participant to shift their vision 11.5 degrees to the right. Then the Participant would throw again, either three or 10 times depending on if they were in the “3 Group” or “10 Group”, the time that the Participant had the glasses on is referred to as the Adaptation Phase. During the Adaptation Phase the trials were conducted in the same manner as before, with the Data Recorder keeping track of the “hits” or “misses” and the Experimenter handing the ball to the Participant and declaring either a “hit” or “miss”. The next step is for the Participant to remove the goggles and begin the After Effect Stage in which they continue to throw until the get five consecutive “hits” as declared by the Experimenter who is still handing them the ball and the Data Recorder writing down the results. Each member of the group gets a turn in each role until all have done each job once. At this time the experiment is finished.
Results
From a sample of 105 participants, 50 were randomly selected. Of these fifty, 25 were from the “3 Group” and 25 were from the “10 Group”. The average number of throws required by the “3 Group” to gets five successive “hits” during the After Effect Phase was 17.64 and the average number of throws taken by the participants in the “10 Group” to get five “hits” in a row was 20.92. A t-test proved that there was no significant difference between the amount of throws required by the “3 Group” and “10 Group” to hit the target five times in a row (t(48)=0.2, p > 0.05). Since the calculated t value was 0.2 this means that a null hypothesis can be accepted.
Discussion
The hypothesis of this experiment was that the “10 Group” would have more substantial after effects as apposed to the “3 Group”.
This calculated results determined that there was very minor relation between the amount of time spent in the adaptation phase and how substantial the effects would be in the after effect stage. “As proven by the experiment, there was very little difference between the two groups. Experiments conducted by Stratton in 1896 suggested that the longer a person had to adjust to a visual field the more accurate their proprioceptive senses would be. “when visual and position senses are in conflict, people learn to adjust the sense of where parts of their body are so that visual and position sense no longer disagree” (Cole, 2013). If the visual field were to be interfered with (as it was with the goggles) the proprioceptive senses would adjust to fit the circumstances. However, the results obtained from the experiment conducted would
disagree. There were many methodological issues that may have skewed the results of this experiment. Had the experiment be conducted in a much more controlled and monitored environment the results could have been more accurate. Several factors may have been involved in sewing the data, such as the demographic. With the majority of participants being in their late teens to early twenties this does not best represent a universal population. Secondly, this experiment was does done primarily with first year university students who, for the most part, were unfamiliar with their classmates. The added pressure of trying to impress their peers could have acted as a factor. To solve these problems the participant could perform the task in a room by themselves so as to eliminate any social anxieties as well as to create a substantially more controlled and monitored environment. Mechanical problems were also an issue in this experiment. If the Velcro on the ball did not stick to the Velcro target than it was up to experimenter to use their best judgment as to whether or not the ball hit the target. Secondly, the target board would tend to sway during the experiment, which increased the difficulty. Having a touch sensitive board that could one hundred percent guarantee a “hit” or “miss” that was also locked into position would solve both of these problems. A potential reason for the unsubstantial difference in results between to the groups may have been caused by the minor difference in time spent during the adaptation phase. In future experiments, there should be a significant time difference in the adaptation phase. The “3 Group” could still have three throws but perhaps give the “10 Group” one hundred, this would give the “10 Group” more time to adapt and theoretically give a stronger effect in the after effect stage. The results of this experiment do not concur with the earlier stated hypothesis. Research in this area of psychology goes a long way back but there is still much more to be explored. Gaining a better understanding of how the afferent and efferent changes work together with one another could lead to many incredible discoveries. For example, developing prosthetic limbs for amputees could take an incredible leap forward if a greater knowledge of this area in psychology were had. The benefits of the brain to adapt to information it is receiving from the senses is immeasurable.
References
Cole, M.R. (2013). Perceptual Adaptation