Reyna Avila

Sonia Ramirez

Eric Culqui

Article Summary:

 

Contributions mainly related to comparative psychology

By

Leland Swenson, Ph.D.

 

Sociobiology and instinctively biased behavior in humans

 

The new natural/social science referred to as sociobiology is a reflection of innate patterns that increase the survival of genes.  Along these lines, it would then hold true that altruism (the cost of one's own life for that of another) is adaptive and in fact is a selfish act on the part of the gene.  Aggression, when viewed in context, can be defined as an improvement in the survival of human genes.  A modern example may be seen in the competition for more resources.  Making that person more desirable a possible mating partner.  Nepotism, the favoring of relatives to that of friends, is also seen in reference to gene survival.  It can be seen as an adaptive behavior.  To the extreme, sociobiological thought would state that love is nothing but DNA acting in its own self-interest.  When presented with these ideas, one can take the next step by assessing patterns of behavior.  For example, based on these definitions, attempting to change traditional sex roles shows a resistance of inherited/ innate behaviors to that of modification of learning.  In other words by attempting to change sex roles we are attempting to relearn an innate behavior pattern.

In the search for an acceptable mate, according to Swenson, natural selection has an integral part in the preferences that people show.  Assortive mating, the tendency for individuals to marry a person who is similar to them, is reinforced in that the similar genes were successful in perpetuating themselves.  Therefore there is a higher degree to which the gene that poses the similar characteristic will survive.  More specifically when choosing a mate, the genders differ.  Patterns such as selection can be attributed to innate characteristics.  For example, it is seen that males tend to be less selective in their choices of possible female partners.  Why?  One possible reason is that because the reproductive cost to the male is less than that of females.  Because females put a great deal of energy in reproduction, they are going to be more selective in their choices.

The bottom line is that sociobiology, on the subject of learning, identifies that there is an evolutionary mechanism or an innate behavioral characteristic, that influences human behavior.

 

 

 

The Misbehavior of Organisms

            A study by Breland and Breland (1961) discovered what they named instinctual drift. This is the interference of instinctual behavior on reinforced behavior. In their study, they were in the process of training raccoons to pick up coins and place them in the slot of a piggy bank for an advertisement. The reinforcement used was food, and as whole, the conditioning was successful. Breland and Breland ran into problems when the raccoons were given two coins to place in the bank. Instead of putting the coins in the piggy bank, the raccoons would pick up the coins, rub them together, place them in the slot of the bank, pull them out and rub them together again. This behavior is similar to food washing behavior found in wild raccoons. The conditioned raccoons associated the task of handling the coins with food, resulting in instinctual drift. This occurrence of natural food related behaviors in the context of food reinforcement supports the adaptive model developed by Staddon and Simmelhag (1971). Their model states that these instances of instinctual drift occur as a result of two things. First, the appropriate motivational context, in the case of the raccoons, was the presence of food in the reinforcement, must be present. The mood of the organism, or in this case, the possibility that the raccoons were hungry is the second criteria.

 

Species-specific defense relations

 

            According to Robert Bolles, avoidance reactions to aversive stimuli may be innate, defensive reactions.  Predators catch their prey more often than not. There is no time to develop a defense mechanism, by trial and error that will allow them to escape future attacks. There for animals that have these innate defense mechanisms are able to survive and successfully pass on their genes.  These reactions are called species-specific defense reactions (SSDR).  They are defined as any new, sudden or aversive stimulus.

            Defense reactions are organized in a hierarchy.  At the peak of the hierarchy are the proponent responses, which are innately organized.  Next are the behaviors that can be learned with moderate ease once the innate responses are suppressed.  At the bottom of the hierarchy are the behaviors that are not familiar to the species or behaviors that are to the contrary of their natural defensive reactions, which are learned with great difficulty.

            Learning certain behaviors may come with difficulty as a result of direct interference from instinctual response patterns.  A study conducted by Bolles (1975), using rats, showed that hey had difficulty avoiding shocks by pressing a bar press and showed their SSDR by freezing.

 

 

The Preparedness Continuum-The relationship of genes to learning

 

            The development of preparedness theory and bait aversion

 

            In the process of developing the theory of Taste Aversion, Swenson naturally leads the reader into the development of the preparedness theory.  Taste aversion can be defined as an organism having a super sensitive reaction to that of taste cues.  In other words, if the animal experiences nausea after the consumption of food, that animal will avoid further contact with that food.  Garcia and Koelling, (in Swenson) conducted research that demonstrates this theory of taste aversion.

            Two groups of rats were allowed to drink a saccharin-flavored solution.  Upon consumption of the solution a tone-light burst was presented with every lick, then followed by either a shock [which will be referred to as group A] or an injection of lithium chloride [will be referred to by group B].  The lithium chloride caused nausea feeling for the rats.  Group A avoided the water, solution or pure, that was presented in the presence of the light burst.  Group B avoided only the solution water and would consume the plain water, regardless of the light burst.  These results suggest that there is an innate mechanism that allows rats to quickly learn by taste cues; Further more to learn by specific taste cues, which allow for the avoidance of potentially harmful foods.

            Looking further into the Taste Aversion theory, it has been shown that novelty tastes are much more easily associated with nausea.  When presented with both a novel taste and a familiar taste then followed by sickness, aversion is only developed to the novel taste.  Swenson hypotheses that the avoidance may occur due to the fact that new foods are more likely to be poisonous than the foods that have been tasted before. 

            Taste aversion has been demonstrated in coyotes as well.  Gustavson and colleagues, (in Swenson), left sheep carcasses with lithium chloride around for the coyotes to consume.  It was reported that captive subjects in fact avoided the sheep as a possible food source.  In so far as to actually run from live ones.  While forms of Taste Aversion can also be seen in Humans a more complicated element arises in that humans may only need one encounter to the poison once in order to learn the behavior of avoidance to that food.  Seligman and Hager (in Swenson), report that a subject went out to eat and hours later he became violently ill with the stomach flu.  Later when he attempted to eat the food that he had eaten the night he got sick, he became nauseated with the mere thought of eating the food.  What does this imply?  According to Swenson none of the learning theories can account for the magnitude and rapidness of the learning.  Therefore he suggests that the laws of contiguity and conditioning be modified to take into account the selective associations of the cues found in innate mechanisms for learning; One such theory has been developed by Seligman. 

Taking into account these innate mechanisms, this learning theory bases it assumption that evolution makes some types of learning easier than others, prepared learning versus contraprepared learning.  Prepared learning being the predisposed learning ability in animals and contraprepared learning being that mechanism that makes it difficult for a learning to occur.  Both of these terms are based on the assumption of the equipotentiality doctrine, which states that all types of learning fit onto a preparedness continuum (Fig. 1).  The continuum begins with total prepared learning (instinct) and ends with Contraprepared learning.  This theory predicts various types of learning based on the evolutionary history of each species.  Seigman and Hager (in Swenson) suggest that the learning of food preferences and food aversion be a prepared type of learning, which would account for the craving of foods and specific hungers, based on the body’s need for specific nutrients.


INSERT FIGURE 1

Evidence for preparedness in other behaviors

 

            Chomsky (1972) and Pinker and Bloom (1992) propose an innate basis for language learning in general and grammar in particular. They feel this is due to the fact that the structure of the human brain prepares infants for fast, durable, and shaped learning of human language that is consistent with appropriate speech. Evidence is present in the research of Gopnik and Crago (1991) who discovered certain irreversible language disorders that were located on specific genes. This lead them to believe that many genetic localized and generalized brain structures are partially responsible for the production of normal human speech. Also, the human vocal tract is highly specialized for speech (Pinker and Bloom, 1992). Some animals such as the great apes, and dolphins can learn to use a form of language, including some grammar. However, no species can reproduce the complexity of human speech. The current popular belief is that speech is a result of Darwinian evolution, while some believe that speech is a by-product of other environmental adaptations.

Pinker and Bloom offer two possible explanations for the existence of multiple human languages. First, the development of new tools and other man made goods would require a learning mechanism to assign sounds to new meanings. Second, is the impossibility of a completely inborn language system. This would take up entirely too much genetic “space” to encode.

            Seligman and Hager (1972) suggest that preparedness also applies to the development of human phobias. They suggest that prepared fears account for the greater number of people who fear snakes as opposed to bees, which kill more people every year than snakes. Seligman also suggests that encounters with bees are far more common than encounters with rats, snakes and spiders, which indicate that fears of the latter three are genetically prepared and easy to learn. Other evidence suggests that fears of social situations can be traced to cognitive or conditioning experience, while the sources of animal fears could not be traced.

Artificially produced phobias are more successful if made within an appropriate context. Evidence for this is found in the research of Lamon, Wilson and Leaf (1977). Their research concluded that nausea-producing effects were more successful in producing aversions to selected beverages than electric shock.

 

Environmental genetics

 

            Plomin & Neiderhiser remark on the genetic influence on personality, psychopathology, and cognitive abilities as now accepted. This was proven through studies conducted on families, twins, and adoptions.

            Now genetic researchers have gone beyond investigating the influences genes have on humans. Their new direction is called environmental genetics. This is defined as a study of how environmental influences are affected by our genetic heritage.

Environmental measures that are measurements of an experience can be seen as extended phenotypes. Phenotypes are gene characteristics that can be seen. Then the usual methods of quantitative genes are expressed in individuals. Next, the usual methods of quantitative genetics are applied. With these methods the average heritability estimates at about .30. Therefore, only about a third of the variance of the environmental measure can be accounted for by genetic differences.

            A multivariate genetic analysis can show the extent of the relationship between an environmental measure and outcome that is genetically mediated. Genetic mediation is the product of paths from latent variable G genes. G genes are the genetic contribution between the environmental and outcome measure. G genes may be capable of making a person vulnerable to a depression or indirectly predispose to other events that can trigger the depression.


INSERT FIGURE 16.3

 


Evolutionary psychology

 

“The central assumption of evolutionary psychology is that current psychological processes were adaptive in ancestral environment (Swenson).” Learning theorists assume that there was not one set of laws that could be applied to all species, reinforcements, stimuli and responses. As a result they did an evolutionary analysis for each species. “As a general rule evolution determines the how of learning for a given species (Swenson).”

            The sensitivity to innateness was studied in the Guthrie and Hortons’ cat puzzle box studies. The cats in the study would rub against a pole that was in the center of the box before escaping. But in later studies, Moore and Stuttard found that they only rubbed against the pole because a human was not in their immediate presence. The cats had learned to rub against humans who did not object to being rubbed. Since the human was not available they substituted him/her with the pole, thus showing how the cat learned to rub against the pole.

            Cognitive psychologists still believe that there is one set of laws pertaining to learning for all species. They just assumed that cognitive mechanisms were used for a general purpose and not for survival needs.

            On the contrary, Evolutionary psychologists say that the brain supports a large number of specialized psychological mechanisms that each is designed by a certain evolutionary problem. Since solutions to problems differ, mechanisms used in finding a mate may differ from one used in finding preferred food. As we have previously learned, “learning is a hierarchical process with specialized brain mechanisms to process different information in different information in different situations (Swenson)”.

            Evolutionary psychology and sociobiology promise to build a deeper understanding by adding layers of analysis to the study of human psychology. 


Reyna Avila

Sonia Ramirez

Eric Culqui

Article Outline:

 

I.) Sociobiology and instinctively biased behavior in humans

-Sociobiology is a reflection of innate patterns that increase the survival of genes. 

 

Key Terms

¨      Altruism is the cost of one's own life for that of another

 

¨      Aggression is an improvement in the survival of human genes.

 

¨      Nepotism is the favoring of relatives to that of friends

 

-Sociobiological thought states that love is DNA acting in its own self-interest.

 

-Natural selection has an integral part in the preferences that people show in mate selection. 

 

-Assortive mating is the tendency for individuals to marry a person who is similar to them, is reinforced in that the similar genes were successful in perpetuating themselves. 

 

-Sociobiology, on the subject of learning, identifies that there is an evolutionary mechanism or an innate behavioral characteristic, that influences human behavior.

 

 

II.) The Misbehavior of Organisms

-Instinctual drift is the interference of instinctual behavior on reinforced behavior.

¨      e.g. Raccoon coin washing behavior

 

-Natural food related behaviors occur in the context of food reinforcement

 

-Staddon and Simmelhag (1971) model states that these instances of instinctual drift occur as a result of two things.

1.      First, the appropriate motivational context

2.      The mood of the organism

 

III.) Species-specific defense relations

 

-According to Robert Bolles, avoidance reactions to aversive stimuli may be innate, defensive reactions

 

-These reactions are called species-specific defense reactions (SSDR) defined as any new, sudden or aversive stimulus.

 

-Defense reactions are organized in a hierarchy.

1.      Proponent responses are innately organized.

2.      Behaviors learned with moderate ease once innate responses are suppressed. 

3.      Behaviors not familiar to the species or behaviors that are to the contrary of their natural defensive reactions, which are learned with great difficulty.

 

-Learning certain behaviors may come with difficulty as a result of direct interference from instinctual response patterns 

 

IV.) The Preparedness Continuum-The relationship of genes to learning

 

A.) The development of preparedness theory and bait aversion

 

-Taste aversion is an organism having a super sensitive reaction to that of taste cues.

¨      e.g. Garcia and Koelling, rat and saccharin-flavored solution research

           

-Learning by specific taste cues allows for the avoidance of potentially harmful foods.

 

-Novelty tastes are much more easily associated with nausea. 

 

-Humans may only need one encounter to the poison in order to learn avoidance.

 

-Seligman innate mechanism learning theory

¨      Assumes that evolution makes some types of learning easier than others Prepared learning vs. Contraprepared learning

¨      Equipotentiality doctrine

§        All types of learning fit onto a preparedness continuum

Total prepared learning (instinct) ŢContraprepared learning

§        Predicts various types of learning based on the evolutionary history of each species.

 

B.) Evidence for preparedness in other behaviors

 

-Chomsky (1972) and Pinker and Bloom (1992) propose an innate basis for language learning in general and grammar in particular.

 

-Structure of the human brain prepares infants for fast, durable, and shaped learning of human language that is consistent with appropriate speech.

¨      E.g. research of Gopnik and Crago irreversible language disorders located on specific genes.

 

-The human vocal tract is highly specialized for speech; no species can reproduce the complexity of human speech.

 

-Current popular belief is that speech is a result of Darwinian evolution, while some believe that speech is a by-product of other environmental adaptations.

 

-Pinker and Bloom offer two possible explanations for the existence of multiple human languages.

1.      The development of new tools and other man made goods would require a learning mechanism to assign sounds to new meanings.

2.      The impossibility of a completely inborn language system.

 

-Seligman and Hager (1972) suggest that preparedness also applies to the development of human phobias.

 

-Artificially produced phobias are more successful if made within an appropriate context. Evidence for this is found in the research of Lamon, Wilson and Leaf (1977).

 

C.) Environmental genetics

 

-Acceptance of the genetic influence on personality, psychopathology, and cognitive abilities more widespread

 

-Environmental genetics is a study of environmental influences that are affected by our genetic heritage.

 

-Environmental measures are measurements of an experience that can be seen as extended phenotypes.

 

-Phenotypes are gene characteristics that can be seen.

 

-Approximately one third of variance of the environmental measure can be accounted for by genetic differences.

 

V.) Evolutionary psychology

 

-Learning theorists assume that there was not one set of laws that could be applied to all species, reinforcements, stimuli and responses.

¨      E.g. sensitivity to innateness was studied in the Guthrie and Hortons’ cat puzzle box studies.

 

-Cognitive psychologists still believe that there is one set of laws pertaining to learning for all species.

¨      Have assumed that cognitive mechanisms were used for a general purpose and not for survival needs.

 

-States the brain supports a large number of specialized psychological mechanisms that each is designed by a certain evolutionary problem.

 

-Since solutions to problems differ, mechanisms used in finding a mate may differ from one used in finding preferred food.