Biological Basis of Behaviour

Music:

“Insane in the Membrane” Cypress Hill

“Comfortably Numb”Pink Floyd

Chapter 3: Agenda• 1. Mind-body Questions• 2. Communication Systems Within the Body:

– a) Endocrine b) Nervous• 3. The Central Nervous System:

– a) The hindbrain– b) The midbrain– c) The forebrain – d) Left and right hemisphere specialization

• 4. The Peripheral Nervous System• 5. Neurons in Action • 6. Tutorial: Practice questions

1. Mind-Body Questions

• Why learn about the brain?

• Is the mind reducible to biological mechanisms?– Biological reductionism

• Two-way interactions:– Can ‘mind’ affect biology?– Reciprocal effects

2. Two Communication Systems Within the Body:

• 1. Endocrine System (p. 106)– Basic building block:

• Hormones released in bloodstream regulate basic body processes

– Endocrine glands: hypothalamus, down to pituitary and others found throughout body

– Fig. 3.23

• 2. Nervous System– Neurotransmitters carry signals between nerve

cells– Central Nervous System: brain & spine– Peripheral Nervous System: extends outward

from the spine to organs and limbs

3. Central Nervous SystemFig. 3.15, p. 96

• a) Hindbrain:– Cerebellum – Medulla– Pons

• b) Midbrain:– Reticular formation

• c) Forebrain:– Thalamus (relay center)– Hypothalamus – Limbic System– Cerebrum

3. c) Forebrain (cont’d)

• Hypothalamus:– Regulation of basic biological drives related to survival

• 4 F’s (including fight or flight response)

– Control of hunger, thirst, sex, body temperature

• Limbic System:– Center of emotion, memory, motivation– Amygdala (emotion)– Hippocampus (memory)– Pleasure Centers

• includes dopamine releasing neurons in hypothalamus

3. c) Cerebrum

Cortex: What makes us distinctively human 100 trillion synaptic connections! 4 lobes:

• Occipital

• Parietal

• Temporal

• Frontal

3. c) Illustration of the 4 lobes

3.c) Frontal Lobes: Motor Cortex

3. d) Right brain/Left Brain

Differentiation of functions See application section for critical appraisal

3. Split-Brain Research (p. 102-103)

4. The Peripheral Nervous System

Beyond the brain and spinal cord Somatic and autonomic nervous system Autonomic:

most relevant for psychology

4. The Autonomic System (p. 89)

Fight or flight Hypothalamic pituitary axis (HPA)

5. Neurons in Action (p. 82-83)

Figures 3.3 & 3.4

6. Tutorial/Practice Questions• Perhaps the greatest advantage associated with descriptive research

methods is: – a) a sensitivity to ethical concerns– b) the isolation of cause and effect linkages in behaviour– c) the ability to focus on specific, isolated behaviours – d) the ability to explore questions that cannot be examined using experimental

procedures

• Maria plans to study the relationship between self-esteem and being raised in a single-parent or a two-parent family. Maria is most likely to chose a correlational method because correlational studies:– a) tend to be more accurate than experiments– b) have higher internal validity than experiments when there are two

dependent variables– c) can be used to investigate factors that would be impossible to manipulate in

an experimental study– d) can be used to study either positive or negative relationships, whereas

experiments can only be used to study positive relationships

Practice Questions (cont’d)

• A correlation coefficient of zero indicates: – a) a positive relationship between 2 variables– b) a negative relationship between two variables– c) the lack of a relationship between 2 variables– d) a perfect relationship between 2 variables

Practice Questions (cont’d)• Imagine that a picture of a spoon is briefly flashed in the

left visual field of an individual with a severed corpus callosum. At the same time, a picture of a cup is briefly flashed in the right visual field. Based on the work with split brain patients, you could predict that this individual will say: – a) “I didn’t see anything.”– b) “I saw a spoon resting in a cup.”– c) “I saw a spoon.” – d) “I saw a cup.”– e) It does not really matter since both hemispheres “talk

to one another.” • Short answer:

– What are the three layers of the brain? Briefly list the functions of one layer.

See you next week!