PSYCH260:

PSYCH 260
Lesson 1 – Introducing Biological Psychology

 

Slide 1 - Lesson 1: Introducing Biological Psychology

 

Slide 2 - Learning Goals

[Slide text: Learning Goals

1. Define biopsychology and outline the main divisions of the field
2. Explain the four major biological explanations of behavior
3. Discuss the difference between behavioral and somatic interventions in biopsychology
4. Apply these concepts to real-life situations]

 

Slide 3 - Lesson Introduction

[Slide text:

"The Brain is wider than the Sky-

For put them side by side-

The one the other will contain

With ease and You beside.

The Brain is deeper than the sea-

For hold them Blue to Blue-

The one the other will absorb-

As Sponges-Buckets-do-"

Emily Dickinson (1830-1886), American Poet]

 

Slide 4 - Lesson Question

[Slide text: How would you define Biopsychology? What comes to mind when you hear this term?]

 

Slide 5 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes.]

INSTRUCTOR: While this is a simple question, there is no agreed upon definition. For example, I earned my degree in applied biopsychology where I studied frontal lobe function. Other students in the same department were studying anything from the electrophysiology of inmates to rodent models of addiction - even motion sickness models for space travel. Yet all of these laboratories fell under the discipline of biopsychology.  In other words, it’s a pretty broad field of study. However, most would maintain that it is a field of science the goal of understanding how various biological systems influence the way we think, feel, and act. Other terms you might have heard that are also sometimes used to describe the field include: biological psychology, behavioral biology, or behavioral neuroscience. Simply put, biopsychology can be outlined as a subdivision of neuroscience, where we interpret psychological constructs through the lens of the nervous system. Due to its diversity, some researchers further differentiate the field into subdivisions. Let’s go ahead and outline 5 of the major divisions associated with biopsychology.

 

Slide 6 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes. Major divisions: physiological psychology.]

INSTRUCTOR: Physiological Psychology focuses on exploring the brain-behavior relationship primarily through psychosurgery and electrical stimulation of the brain.  Due the extreme nature of these experimental designs, a majority of laboratory work within physiological psychology is carried out on animals.  In general, while the results of physiological studies greatly assist the development of neuroscientific theories, they tend to lack immediate practical benefit.

Slide 7 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes. Major divisions: physiological psychology, psychopharmacology.]

INSTRUCTOR: A 2nd subdivision of biopsychology is psychopharmacology. As you’ve probably already guessed by the name, this approach uses various chemical compounds and drugs to manipulate neural circuits. In contrast to physiological psychology, those in this area of study are more likely to use human subjects in experiments and the results are more likely to have direct applications.

 

Slide 8 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes. Major divisions: physiological psychology, psychopharmacology, neuropsychology.]

INSTRUCTOR: On the other hand virtually all neuropsychological studies involve human participants. This particular approach often focuses on the impact of traumatic brain injury including diagnosing, assessment of function, and recommendations for rehabilitation. Because of this, neuropsycological studies are more likely to involve case studies. However, it is considered to be one of the most applied divisions as the results of their studies are more likely to have a direct benefit for the participants being assessed.

 

Slide 9 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes. Major divisions: physiological psychology, psychopharmacology, neuropsychology, psychophysiology]

The goal of cognitive neuroscience is to uncover the neural basis of cognitive functioning. Research often involves examining brain function activation and changes during mental tasks. Recording is usually done with the help of modern imaging techniques. This division is considered a relatively new but rapidly growing area within biopsychology primarily due to significant advances in imaging technology over the past several decades.      

 

Slide 10 - Defining the Field

[Slide text: What is biopsychology? Study of the influences of biological systems on behavior, emotions and mental processes. Major divisions: physiological psychology, psychopharmacology, neuropsychology, psychophysiology, cognitive neuroscience.]

The goal of cognitive neuroscience is to uncover the neural basis of cognitive functioning. Research often involves examining brain function activation and changes during mental tasks. Recording is usually done with the help of modern imaging techniques. This division is considered a relatively new but rapidly growing area within biopsychology primarily due to significant advances in imaging technology over the past several decades.      

Slide 11 - Defining the Field

Biopsychology Division	Applied Examples to the Study of Memory
Physiological Psychology	Removal of the hippocampus in a group of rats and studying the impact on memory tasks.
Psychopharmacology	Investigating the impact of certain acetycholinergic drugs designed to assist Alzheimer's patients.
Neuropsychology	Assessing potential memory impairments of a patient after a work-related head injury.
Psychophysiology	Examining the change in galvanic skin response to familiar faces.
Cognitive Neuroscience	Utilizing an fMRI to examine which areas of the brain are activating while participants engage in a spatial memory task.

INSTRUCTOR: Take a look at the table here for an example of how each division might approach the study of memory. A physiological psychologist might remove certain areas of the brain, such as the hippocampus, in a sample of rats. Then record how it impacts their memory. For example, they may have them run a maze repeatedly, recording the number of errors and how long it takes them to reach the end. This data could then be compared to a control group of rats, who haven’t had their hippocampus removed.

A psychopharmacologist on the other hand might study the impact of certain drugs made to slow down the progressive decline in memory functioning found in dementias. Many of these drugs increase the efficiency of a neurochemical called acetylcholine. Thus, one study might include testing the effectiveness of a new acetylcholinergic drug on a group of Alzheimer’s patients. A neuropsychologist might see patients who were injured at the work place and have filed for workman’s compensation. One of the chief complaints related to traumatic brain injury is lingering memory difficulties. A neuropsychologist may be called in to test the validity of the memory complaints with such cases. Additionally, they can assess the severity of the memory deficits as well as provide feedback on capacity of functioning and outcome.

A psychophysiology study of memory might include analyzing changes in the autonomic nervous system to the presentation familiar and unfamiliar faces. For example, they may use a galvanic skin response recorder (known as a GSR) to assess these changes. A GSR is a small device usually placed on the hand and/or fingers of the individual. It’s extremely sensitive to changes in electrical conductance across the surface of the skin. This conductance has been found to change in response to triggering of emotions, such as those evoked from familiar faces. Finally, a cognitive neuroscientist might design a study where they record the ongoing changes to activity in the hippocampus during a memory examination. For example, the study could require participants to lie in a functional magnetic resonance imager (or fMRI) while trying to recall a list of words presented earlier in the study. While they tend to be expensive, many of the modern imaging techniques have the advantage of not being invasive. In other words, there isn’t any penetration of tissue, which is more common in physiological psychology studies.

 

Slide 12 - Lesson Question

INSTRUCTOR: In the previous table, I hypothesized how one might approach the study of memory from each of the five subdivisions of biopsychology. For practice, why don’t you think of another construct and try to hypothesize how each division might study it.

 

Slide 13 - Defining the Field

[Slide text: Main biological explanations of behavior:

• Cytoarchitectonic Explanation: directly ties behavior to brain and neurochemical functioning
• Ontogenetic Explanation: integrates the behavior as a function relying on developmental trajectories]

INSTRUCTOR: While there are a number of different subdivisions, explanations of behavior within the field often fall into one of four main categories. The first explanation, which is also probably the most often represented, is the Cytoarchitectonic approach. This explanation focuses on determining the structures of the brain involved with engaging in the task. To this extent, it also includes investigations into neurochemical correlates. Ontogeny is defined as the progressive growth of an individual. So, an ontogenetic explanation would be searching for relationships between the behavior and certain developmentally related issues. For example, an ontogenetic explanation might state that language development is based on exposure. And this exposure must occur during a critical window of time during one’s development. The ontogenetic explanation focuses on the progressive developmental changes in an individual’s lifespan.

 

Slide 14 - Defining the Field

[Slide text: Main biological explanations of behavior:

• Evolutionary Explanation: examines the evolutionary history and origins of an existing behavior
• Functional Explanation: attempts to describe why a structure or behavior came into being in the first place]

INSTRUCTOR: In comparison, the evolutionary approach is searching for explanations of behavior over many generations. In other words it uses a more Darwinian perspective for explaining the relationship between neural systems and the expression of behavior. The fourth explanation is functional. As its name implies, this explanation outlines why the behavior exists in the first place. What purpose or function does it serve. If you recall your intro psychology lessons, you can see that it closely follows the functionalism paradigm introduced by William James. In the end, while a biopsychologist may focuses on one of these explanations more than another, possibly due to their subdivision specialization for example - a good biopsychologist recognizes and acknowledges all of these perspectives as possible explanations of behavior.

Slide 15 - Defining the Field

[Slide text: Application example: Yawning

• Cytoarchitectonic
• Ontogenetic
• Evolutionary
• Functional]

Yawn! To further illustrate the differences among these explanations, let me use an example of a common behavior to all of us, yawning. Before I give you explanations for all these perspectives though, I want you to try and think of types of questions you might pose for all four of them. For example, what types of questions would someone looking for a Cytoarchitectonic explanation ask? What would they be looking for in their research? Once you’ve had time to come up with your own questions, click to continue and I’ll provide you with some of the research results from each of the different explanations.

You might have asked why yawns are contagious. One evolutionary perspective is that the yawn once served a purpose to communicate a time to relax after a period of high alert in a large community of people. As almost representing an “alls clear” signal, the yawn would pass amongst the group, spreading the word quickly. While this behavioral means of communication may no longer be needed, it still remains. In a way then, they would say that a yawn represent the appendix of behavior. We’ve evolved to no longer need it, but it still exists. Not many researcher support the evolutionary explanation for why we yawn.  Instead they offer a number of other functional explanations.

For example, some believe that yawning allows us to get more oxygen at critical points. So when we yawn we expel a large amount of CO2 and take in a larger amount of oxygen.  Unfortunately, studies investigating this functional explanation have not been supported. For example, in one study they placed participants in rooms varying in concentrations of CO2 and oxygen. However, they didn’t find that there was a difference in the amount of yawns produced across the groups. Another functional explanation suggests that yawning helps cool down the brain. It’s essentially the human version of panting. To investigate this explanation, one study had participants hold either a hot or cold pack to their foreheads while watching a television program. In support of this explanation, they found those will the hot packs were more likely to yawn. Again, not everyone agrees with this explanation  For example, one caveat is that other species which pant, such as dogs, also yawn. Why would they have two mechanisms for the same function? Finally, others have suggested that yawning is a good stretch – temporarily increasing the blood flow and heart rate of the individual. This would lead to an increase in attention and alertness in the individual. Supporters of this functional explanation state this is the reason we yawn when we first wake up, when we’re bored, or trying to stave off sleep.

 

Slide 16 - Lesson Question

[Slide text: What types of questions might be asked by each of these biological explanations in regards to the behavior you came up with previously?]

INSTRUCTOR: You can see here that something as simple as a yawn is still a bit of an enigma for researchers. Why don’t you go ahead and imagine how you might investigate each of the possible explanations for the behavior you suggested on the last Lessons Question slide.

 

Slide 17 - Defining the Field

[Slide text: Researchers often look for circular relationships between the brain and behavior.

• Somatic interventions: investigating the impact of manipulating brain structure or function on behavior
• Behavioral interventions: intervening in the ongoing behavior of an individual and recording the resulting changes in brain structure and function]

Researchers often look for circular relationships between the brain and behavior. The two main types being Somatic and Behavioral Interventions. Now before we begin, t to understand these two types of interactions, we need to do a quick review of experimental designs from introductory psychology. Remember, that an experimental design is looking for a cause and effect relationship. In order to do so, the experimenter does the best they can to hold all variables between the control group and experimental group constant – except for one. The independent variable. In a perfectly controlled experiment then, only the independent variable is manipulated between the groups. Both groups – the experimental and control groups – are then measured on a particular outcome variable, known as the dependent variable. The researchers are looking for differences between the groups on this particular outcome variable. If a difference occurs, then they conclude it was caused by the manipulation they presented in the independent variable. In other words they conclude that the independent variable had a direct impact on the dependent variable. 

Going back to our interventions then, somatic and behavioral approaches both are looking for that cause-effect relationship between the brain and behavior. However, which one (the brain or the behavior) that is labeled the independent variable and which one that is labeled the outcome variable differentiates between these two intervention types. In a somatic intervention, a biological component, such as a hormone or brain tissue, is manipulated. Thus, the independent variable is the biological component of the equation. The potential resultant change in behavior is considered the dependent variable.  Essentially, the biology is the independent variable and the behavior is the dependent variable in a somatic intervention. 

For example, think back to the example of the hippocampus I used when describing the physiological approach. In that example the experimental group had their hippocampus removed. A biological system was manipulated. They then looked for changes in behavior, essentially how well they could run a maze. This is a dependent variable and is behavioral in nature. In a behavioral intervention, the roles of brain and behavior are reversed.  The neural systems are considered the outcome variable while some aspect of behavior is manipulated. For example, imagine if we are studying Alzheimer’s patients. Now, imagine if we request patients in the experimental group to exercise using the Nintendo Wii every day for one hour. After several months we then investigate if there is any difference between the control group and the experimental group of patients in acetylcholine production.  In this example, we’ve manipulated the behavior between the groups – whether or not they received a regular regiment of exercise. A biological component was our outcome variable – we wanted to see if it made any difference in the amount of acetylcholine produced.

 

Slide 18 - Defining the Field

[Slide text: Somatic variables --> Somatic intervention --> Behavioral variables --> Behavioral intervention --> Somatic variables, etc. ]

INSTRUCTOR: Take a look at this figure here. Considering both somatic and behavioral interventions, biological psychologists are really looking for circular relationships existing between brain and behavior.

Slide 19 - Defining the Field

[Slide text: Application Example: Aggression and Testosterone (Somatic Intervention)]

Somatic Approach – Dilantin is a drug primarily used to help control epileptic seizures. However, researchers also serendipitously noticed that this anti-epileptic drug appeared to reduce impulsive violent acts. To investigate this relationship further, one research group studied its impact on prison inmates with a history of impulsive aggression. In the study, only half, the experimental group, was actually given the drug. The control group was given a pill that looked like the dilantin tablet, but was a generic inert substance. In other words, they were given a placebo. The variable under manipulation in this study was the drug – and its known biological effects. The outcome variable that was measured was behavioral in nature; the amount of violence displayed by both groups during the study. The researchers did find significant differences between the two groups, with dilantin reducing the amount of violent behaviors reported by the experimental group.

Slide 20 - Defining the Field

[Slide text: Application Example: Aggression and Testosterone (Somatic Intervention, Behavioral Intervention)]

INSTRUCTOR: Our behaviors can also influence biological systems. For example, being exposed to violent acts in the media can temporarily influence levels of testosterone, which is implicated in aggression. Some studies have found a tie to sporting events. One group of researchers reported that if your team wins, there is a temporary but significant increase in testosterone levels. If however, your team loses the match, then testosterone levels actually dip for a period of time. This fluctuation in neurochemistry was only seen if the participants had an invested interest in the team. In this particular study, the manipulated variable was the behavioral experience of whether or not their team won the game. The recorded outcome variable was biological in nature; the change in overall testosterone levels.

Slide 21 - Conclusion of Lesson 1

INSTRUCTOR: This brings us to the conclusion of our first lesson. Stay tuned – in our next lesson we’ll follow the origins of biopsychology as a field.