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The current manuscript was submitted to American Journal of Psychology in Sept 2023. It is a revision of a manuscript submitted to Psychological Review in Jun 2023 and an additional revision of the same manuscript that was submitted to New Ideas in Psychology in Jul 2023.
The submission to Psychological Review appears as a post in Visual Perception Science with a date of Jun 6 2023. The submission to New Ideas in Psychology appears as a post in Visual Perception Science with a date of Oct 10 2023.
The start of the Oct 10 2023 post in Visual Perception Science indicates a theoretical error in the manuscript submitted to Psychological Review. Accordingly, the manuscript submitted to New Ideas in Psychology is a revision of the manuscript submitted to Psychological Review. Nevertheless, the majority of the revision is essentially the same as the manuscript submitted to Psychological Review.
The current manuscript that was submitted to American Journal of Psychology is a condensation of the manuscript submitted to New Ideas in Psychology. Otherwise, the current manuscript is similar to the manuscript submited to New Ideas in Psychology, although it should be an improvement of it.
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Abstract
A proposition: A single assimilation process enables (contributes to bringing about) several general results. Accordingly, the following statements are supported. A perceived location assimilates (becomes similar) to a different perceived location. A perceived three-dimensional (3D) location assimilates to a different perceived 3D location. A perceived conditioned stimulus assimilates to a retained unconditioned stimulus and thereby the conditioned response occurs. A perceived response-correlated-stimulus completely assimilates to (matches) a retained stimulus produced by the instrumental response and thereby the instrumental response occurs again. (A response-correlated stimulus is the stimulus that accompanies the execution of a response.) An observer’s perceived response-correlated-stimulus assimilates to a retained stimulus produced by a demonstrator’s response and thereby delayed imitation occurs. A young animal’s perceived fear assimilates to the perceived calmness (absence of fear) produced by stimuli of a mother and hence its fear is reduced. The assimilation process also enables contrast.
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A proposition to be supported is that a perception becomes similar (assimilates) to another perception or retention of a perception for perceived location, perceived three-dimensional (3D) location, classical conditioning, instrumental conditioning, delayed imitation, and a mother decreasing a young animal’s fear. Assimilation is basically defined as occurring when a perception becomes similar to including the same as another perception. Presumably, a single process of assimilation enables all of these general results and conceivably also the general result of contrast. (Enables means contributes to bringing about.) Each of these general results is covered in a separate section.
1. A Perceived Location Assimilates to Another Perceived Location
A result is that the location of a target object is perceived as similar (assimilated) to the location of a nontarget object (e.g. Ganz 1964; Prinzmetal, 2005; Rentschler, Hilz, & Grimm, 1975). For example, the location of a lower luminance vertical target line was perceived as similar to the location of an adjacent higher luminance vertical nontarget line (Rentschler et al.).
In accord, assimilation between perceived locations will be said to occur. Likewise, an object will be said to assimilate to the perceived location of another object (not only a nontarget object). Assimilation between perceived locations is also called “attraction” (e.g. Smith, 1954) and “spatial compression” (e.g. Born, Kruger, Zimmermann, & Cavanagh, 2016).
When assimilation between perceived locations occurs, the locations of objects may not be consciously perceived. For instance, only a target object’s assimilation-produced location may be consciously perceived. Still, encodings for (neural information of) assimilation-involved locations should exist.
A claim is that assimilation between perceived locations occurs broadly. This claim is supported in the remainder of this section.
Assimilation between perceived locations was complete (100%) (Morrone, Ross, & Burr, 1997). The target’s duration was quite brief, it appeared at about the time a saccade was executed, the second object was the goal for a saccade, and the target was perceived at the goal object’s location. In addition, a target was perceived at almost the same location as a nontarget when the target’s duration was rather brief and also when its contrast was rather low (Born et al., 2016).
Assimilation between perceived locations can occur when a target and second object appear simultaneously (e.g. Ganz, 1964; Rentschler et al., 1975). The target and second object can also partially overlap in time of occurrence (e.g. Smith, 1954; Zimmermann, Fink, & Cavanagh, 2013). They can also appear at nonoverlapping times (e.g. Cicchini, Binda, Burr, & Morrone, 2013; Yamada, Kawabe, & Miura, 2008). When a target and two nontargets appeared, the target’s perceived location became similar to the location of one or the other nontarget depending on the similarity between the target’s tilt and one of the nontarget’s tilt (Cicchini et al.). A target assimilated to the location of a moving object (Eagleman & Sejnowski, 2000).
Arguably, assimilation enables an accurate perceived location when an object in space produces disparity. An object in space that produces a relatively large disparity is known to result in diplopic percepts (e.g. Vieth, 1818, as cited in Howard, 2002). Also, a diplopic percept’s perceived location became similar (assimilated) to the second diplopic percept’s perceived location (Rose & Blake, 1988; Werner, 1937). This result supports the possibility that when an object in space produces a relatively small disparity, each diplopic percept’s original location assimilates to the other diplopic percept’s original location by the same amount and to a sufficiently large extent that the two assimilation-produced perceived locations become the same, equivalently, come to be at the unweighted average of these diplopic percepts’ original locations. Because these two assimilation-produced perceived locations would be the same, they would likely become integrated (perceived as one location). Hence one location that is at the unweighted average of the locations of the diplopic percepts’ original locations could be perceived. Furthermore, this perceived location would be accurate.
Arguably, assimilation between perceived locations occurs very rapidly. Support for this possibility begins with the result that when a saccade is to be aimed (land) at a target and a nontarget is also present, the aim of the saccade is somewhat (or more than somewhat) similar to the location of the nontarget (Bucker, Belopolsky, & Theeuwes, 2015; Coren & Hoenig, 1972; Findlay & Gilchrist, 1997). The perceived location of a target is also similar to the location of a nontarget per this section’s opening paragraph. In addition, a proposition about saccades is that a saccade’s aim toward an object (the saccade’s landing position) indicates the object’s perceived location. Evidence is that an association exists between a saccade’s aim toward a target and the target’s perceived location per traditional measures of perceived location (Aitsebaomo & Bedell, 1992; Miller, 1980; Vishwanath & Kowler, 2003). For instance, the perceived location of a target was relatively accurate per both the aim of a saccade toward its location and the reproduction of its location (Miller). In addition, the same association also exists per the results of different papers (Hadani, Meiri, & Guri, 1984 and Heeman, Van der Stigchel, Munoz, & Theeuwes, 2019; also, Donk & van Zoest, 2011 and Zehetleitner, Krummenacher, Geyer, Hegenloh, & Muller, 2011). For instance, the perceived location of a lower luminance single object was less accurate than that of a higher luminance single object per both the accuracy of a saccade’s aim toward the target (Heeman et al.) and the accuracy of a judgment of the target’s perceived location (Hadani et al). Given the validity of this proposition about saccades, this paragraph’s previously indicated saccade results (e.g. Coren & Hoenig) reveal that the target assimilated toward the perceived location of the nontarget. The latency of a saccade is fast in general. In addition, when a saccade’s aim was similar to the location of a nontarget, its mean latency for some conditions was less than 200 ms (Findlay & Gilchrist). In conclusion, the possibility that assimilation between perceived locations occurs very rapidly has been supported.
2. A Perceived 3D Location Assimilates to Another Perceived 3D Location
When the three-dimensional distance (3D) of an object differs from that of another object, each object’s location will be called a 3D location. This section provides evidence that an object’s 3D perceived location becomes similar (assimilated) to another object’s perceived 3D location. Assimilation between perceived 3D locations will be said to occur.
There is broad evidence that assimilation between perceived 3D locations occurs (Gogel, 1965). One piece of evidence from Gogel is that monocular viewing of threads that were at different physical 3D locations resulted in the perception of these threads at the same 3D (Judd, 1893, as cited in Gogel 1965). Presumably, assimilation-produced averaging of the different perceived 3D locations of the threads occurred. Another result is that a target’s perceived 3D was similar to a near panel’s physical 3D and that the same target’s perceived 3D was also similar to the panel’s far physical 3D (Gogel, 1964). There is more evidence (e.g. Foley & Richards, 1978; Westheimer, 1986). For example, dichoptic lines that produced crossed disparity and dichoptic lines that produced uncrossed disparity resulted in the perception of two lines at the same 3D (Foley & Richards).
Evidence also comes from the perception of drawings with depth. For example, the 3D location of an internal white area of a line drawing of a cube is perceived as similar to the perceived 3D location of a rather close point on a line of this drawing per anecdotal evidence.
3.0. A Perceived CS Assimilates to a Retained US
This section supports the theory “that the CS assimilates to the US” (D. L. King, 2001, p. 35). Likewise, via an assimilation process, the perception of a CS becomes sufficiently similar (assimilated) to a retained US for this perception to result in the CR. A retained stimulus is the retention of a previously perceived stimulus. A CS, US, and CR are a conditioned stimulus, unconditioned stimulus, and conditioned response, respectively. Although the CS and the next two section’s “response-correlated stimulus” may not be consciously perceived, they should be encoded.
Support for this assimilation theory is that CS-US pairings can result in a CR that is highly similar to the unconditioned response (UR). This result is support, because the high CR-UR similarity may be due to the perception of the CS as highly similar to the retained US. Evidence of this highly similar perception includes that pairing the illumination of a plastic response key with food made pigeons peck the key as they do when they perceive food (Jenkins & Moore, 1973). Also, pairing the entering of a ball bearing into an experimental enclosure with food made rats put the ball bearing into their mouths (Timberlake, Wahl, & D. A. King, 1982).
Assimilation theory works for less dramatic CRs. For example, the classical conditioning of salivation using food is attributable to a CS-produced partial perception of food, likewise, an image of food. In addition, this partial perception produces the salivation CR. Support for this attribution is that when humans have an image of food, they often salivate. Additional less dramatic CRs are also attributable to a CS-produced partial perception (image) of the US. This is because “images of stimuli lead to responses similar to the ones produced by real stimuli” (D. L. King, 1973, p. 403).
A word (e.g., “red”) is frequently paired with its referent (e.g., a red color). Also, the familiar Stroop result is evidence that a word can result in the partial perception of its referent. Hence assimilation theory is supported.
More evidence for assimilation theory is that a CS resulted in verbal responses that suggest that the CS was perceived as similar to the US (Ellson, 1941; Powers, Mathys, & Corlett, 2017). In addition, such verbal responses were associated with activation of a brain region that is also activated by perceiving the US (Powers et al.).
4. A Perceived Response-correlated Stimulus Completely Assimilates to the Retained
Response-Correlated Stimulus that Accompanied the Instrumental Response
This section supports an assimilation theory of instrumental conditioning. The reward learning type of instrumental conditioning is covered.
A response-correlated stimulus is the stimulus that accompanies the execution of a response; a currently perceived response-correlated stimulus means that a response is being executed. The assimilation theory of instrumental conditioning maintains that an assimilation process enables a response-correlated stimulus to be perceived as extremely similar to, that is, match, the retained response-correlated stimulus that accompanied previously executed instrumental responses (or only one of them). The indicated match means that the assimilation-enabled perceived response-correlated stimulus and the execution of the instrumental response occur together, thus explaining how the instrumental response occurs again. Similarly, “The animal brings about a match between a response-produced stimulus and an image of the same stimulus” (D. L. King, 1979, p. 449) and thus the instrumental response occurs again.
The assimilation theory of instrumental conditioning is supported by classical conditioning’s occurrence as follows. The stimulus that is correlated with an execution of an instrumental responses should be a CS, because it is paired with the reward that the instrumental response produces. Similarly, classical conditioning should occur between “the response-produced stimuli and the goal” (D. L. King, 1974, p. 1115). In addition, it is known that animals instrumentally respond to perceive a CS (this CS is called a conditioned reinforcer). Hence an animal should attempt to perceive the CS of the stimulus that is correlated with an execution of the instrumental response. Presumably this attempt is successful, because this success explains why the instrumental response occurs again. Finally, the reason that this attempt is successful is that an assimilation process enables a perceived response-correlated stimulus to match the retained response-correlated stimulus that accompanied previously executed instrumental responses (as the preceding paragraph also maintains).
5. An Observer’s Perceived Response-correlated Stimulus Assimilates to the Retained
Response-Correlated Stimulus that Accompanied a Demonstrator’s Response
Recollecting, a response-correlated stimulus is the stimulus that accompanies an executed response. Hence an imitated response occurs when an observer produces a response-correlated stimulus that is similar to the perceived stimulus produced by a demonstrator’s response. Thus imitation reveals that a perception becomes similar (assimilated) to another perception. Accordingly, an assimilation theory of imitation is that an assimilation process enables an observer’s response-correlated stimulus to be perceived as similar to the perception of the stimulus that accompanies a demonstrator’s response. Also, because the observer’s perceived stimulus is response-correlated, the imitated response is executed.
Delayed imitation supports the assimilation theory of instrumental conditioning as follows. The assimilation theory of imitation for specifically delayed imitation is that an assimilation process enables an observer’s response-correlated stimulus to be perceived as similar to the retained response-correlated stimulus that accompanied the demonstrator’s response. The imitation theory for instrumental conditioning (section 4) is about analogous: An assimilation process enables a response-correlated stimulus to be perceived as extremely similar to, that is, match, the retained stimulus that accompanied previously executed instrumental responses. Similarly, “The matching involved in delayed imitation appears to be quite similar to the matching that occurs in straightforward instrumental conditioning” (D. L. King, 1979, p. 449). In addition, the similarity between an observer’s response-correlated stimulus and a demonstrator’s prior response-correlated stimulus can be obvious to a third party. Furthermore, delayed imitation occurs widely. For example, delayed imitation of visually perceived responses by rats (Will, Pallaud, Soczka, & Manikowski, 1974) and dogs (Fugazza & Miklosi, 2014) occurred. Because the assimilation theories for delayed imitation and instrumental conditioning are about analogous, the similarity between an observer’s response-correlated stimulus and a prior demonstrator’s response-correlated stimulus can be obvious, and delayed imitation occurs widely, the assimilation theory of instrumental conditioning theory is supported.
Delayed imitation’s occurrence additionally supports the assimilation theory of instrumental conditioning. An observer’s perceived response-correlated stimulus is frequently somewhat different from a perceived demonstrator’s response-correlated stimulus. For example, the perceived stimulus produced by touching an ear is somewhat different for an observer and a demonstrator. Hence it should be relatively difficult for an observer to extract the similarity between its perceived response-correlated stimulus and the demonstrator’s response-correlated stimulus. The overcoming of this difficulty increases the probability that the about theoretically analogous instrumentally conditioned response is also enabled via an assimilation process.
6. A Young Animal’s Perceived Fear Assimilates to the
the Perceived Calmness Produced by Stimuli of the Mother
A young animal’s perception of fear is produced by a novel (strange) stimulus and also by a punishing stimulus (a first conclusion). A young animal’s perception of calmness (absence of fear) is produced by stimuli of a mother or substitute mother (a second conclusion). A young animal’s perception of fear is decreased by stimuli of a mother or substitute mother (a third conclusion).
The third conclusion is explained by an assimilation theory. The theory posits that an assimilation process enables the perceived fear to become similar (assimilate) to the perceived calmness (absence of fear) and this is why the perceived fear is decreased. This theory is supported because it explains the decrease in fear.
The third conclusion is supported by the result that young animals that perceive a fear producing stimulus approach, remain close to, and/or contact the mother. These responses presumably occur because they increase the perception of calmness likewise decrease the perception of fear. Some decrease in fear results follow. Young monkeys that perceived a novel object were relatively likely to approach a cloth mother and tactually contact her (Harlow & Zimmermann, 1959). Young dogs that were both physically punished and rewarded by an experimenter were more likely to remain close to and in contact with the experimenter than young dogs that were only rewarded (Fisher 55, as cited in Rajecki, Lamb, and Obmascher, 1978). Young birds exposed to novel stimuli exhibit less fear when they remain close to their imprinting object (Moltz, 1960).
7. An Assimilation Process May Enable Contrast
This section provides an account of how an assimilation process may enable the general result that the similarity between different perceived parts decreases. This decrease is frequently referred to as contrast, as it will be here. A perceived part can be both a perceived location and a perceived feature. One contrast result is that when a line and an adjacent square were less near, the line’s perceived location became less similar to the square’s location (Ganz, 1964). The account follows.
A single physical element results in multiple neural values that are on the same neural dimension. For example, a point with a certain intensity results in these multiple neural values. The nervous system also computes an average of these multiple neural values. This average is called a neural average. An average is a single event. Hence the neural average is a single neural event. Critically, the neural average results in a single perceived part on a perceptual dimension.
Accordingly, two elements frequently result in two sets of multiple neural values that are on the same neural dimension. Hence two ensuing neural averages that are on the same neural dimension frequently occur. Thus these two neural averages ordinarily result in two perceived parts on the same perceptual dimension.
For exposition, a first element results in two neural values on a neural dimension. Also, these neural values are 0 and 6. Hence the first element results in a neural average of 3. Thus the element-produced first perceived part is 3 when the element occurs individually (alone). Additionally, for exposition, a second element also results in two neural values that are on the same neural dimension. Also, these neural values are 7 and 13. Therefore the second element results in a neural average of 10. Consequently, the element-produced second perceived part is 10 when the element occurs individually. Accordingly, these two perceived parts are on the same perceptual dimension.
In addition, an assimilation process operates on neural values that are on the same neural dimension. Also, this assimilation process operates similarly to a way that assimilation between locations frequently occurs. This way is that a target assimilates toward a nontarget but hardly vice versa (e.g. Born et al., 2016; Ganz, 1964; Rentschler et al., 1975). Hence an assimilation process may change an element’s neural values or it may not.
In accord with the preceding paragraph, when the first and second elements appear at about the same time, the first element’s neural values of 0 and 6 assimilate (become similar) to the neural values of 7 and 13, whereas the second element’s neural values of 7 and 13 are unchanged. The amount of this assimilation is called moderate. This moderate assimilation results in the first element’s neural values of 0 and 6 becoming, for exposition, 2 and 8, respectively.
The first element’s assimilation-produced neural value of 8 is larger than the second element’s unchanged neural value of 7. Critically, consequently the neural value of 8 no longer affects the neural average that the first element results in. The first element’s sole remaining neural value is 2. Hence the first element’s neural average is also 2. Thus the first element produces a first perceived part of 2.
Summing, when the first element appears individually, the first perceived part is 3. Also, when a second element appears at about the same time and hence an assimilation process operates, the first perceived part is 2. Additionally, the second perceived part continues to be 10. Hence the first perceived part of 2 is less similar to the second perceived part of 10 when an assimilation process operates than when it does not. Thus the possibility that an assimilation process enables contrast between perceived parts is supported.
The described assimilation process also brings about assimilation. The same two elements and their neural values when these elements occur individually are used for exposition. Now the first element’s two neural values assimilate toward the second element’s two neural values by a greater extent that is called sizable. The second element’s two neural values are again unchanged. The sizable assimilation results in the first element’s neural values of 0 and 6 becoming, for exposition, 4 and 10, respectively. The first element’s neural value of 10 is larger than the second element’s neural value of 7. Critically, therefore the first element’s neural value of 10 no longer affects the neural average that the first element results in (analogous to the claim for moderate assimilation). The first element ’s sole remaining neural value is 4. Hence the first element’s neural average is also 4. Thus the first perceived part is 4.
Summing, when the first element appears individually, the first perceived part is 3. Also, when the second element also occurs and when the assimilation is sizable, the first perceived part is 4. Additionally, the second perceived part continues to be 10. The perceived part of 4 is more similar to the perceived part of 10 than is the perceived part of 3. Hence the first perceived part assimilates (becomes similar) to the second perceived part, as to be explained.
How an assimilation process may enable contrast has been indicated. An assimilation process may also enable assimilation between locations, assimilation between 3D locations, classical conditioning, instrumental conditioning, delayed imitation, and a mother decreasing a young animal’s fear per the preceding.
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