Lecture 2: GLOBAL ISSUES OF BIOLOGICAL PSYCHOLOGY Sept 29th, 2015 Lecture Outline

Transcription

1 Lecture 2: GLOBAL ISSUES OF BIOLOGICAL PSYCHOLOGY Sept 29th, 2015 Lecture Outline 1) More about the Mind/Brain Problem Monism vs. Dualism, Results of Survey 2) Different Levels of Psychology Social, Cognitive, Developmental, Biological 3) Different Levels of Biological Psychology Physiological, Ontogenetic, Evolutionary, Functional 4) Correlational, Causal, Necessary Evidence 5) Examples of Physiological Bases of Bird Song

2 Physiological Psychology attempts to understand the neural bases of: 1) Mentation or The Mind : Sensation, Perception, Thought 2) Behavior e.g., Emotion, Sexual, Language, Sleep Does the Mind = Brain? Dualism vs. Monism Dualism The mind exists independently of the brain, the two are of different substances (brain = physical, mind = metaphysical) Interactionism: the brain and mind interact, René Descartes, 1600s (Brain <-> Pineal Gland <-> Mind). Parallelism: mind and brain exist separately, but do not affect each other.

3 Monism The mind is the brain! Identity position: Mind and brain are two ways of talking about the same thing. *** Mentalism: The material word exists only in one s mind (i.e., the physical world is an illusion ). Materialism: The brain is a material machine and consciousness is irrelevant (i.e., the mind is an illusion or an epiphenomenon ). A practical question: Can the mind study the mind?

4 Different Levels of Psychology LANGUAGE example: a behavioral and mental process Social Psychology: How do social pressures influence speech? (e.g., peer vs. non-peer audience?) Cognitive Psychology: Does expectation or context affect language production/comprehension? (e.g., homonyms and unintentional puns ) Developmental Psychology: How and when does language develop? Is there a critical period for the acquisition of language? Biological Psychology: What are the neural underpinnings for the production and comprehension of language?

5 3) Functional: understanding why a structure or behavior evolved. How did a particular gene increase reproductive success? - e.g., Monogamy vs. Polygamy - e.g., Infant/Parent Similarities (N. Christenfeld) - e.g., Homosexuality- benevolent uncle, or maybe just survived in gene pool because gay men were still forced to procreate (and stay in the closet) 4) Evolutionary: relating a structure or behavior across species (Similar to comparative biology) - e.g., effects of sex hormones on sexual behaviors). Different Levels of Biological Psychology SEX example: a behavioral (and mental?) process 1) Physiological: understanding how the nervous system functions and is responsible for a given mental process or behavior (i.e., neural underpinnings of sexual behavior) 2) Ontogenetic: understanding how a structure or behavior develops (i.e., development of sexual behavior)

6 HOW TO INTERPRET DIFFERENT TYPES OF EVIDENCE: As scientists, we want to know what causes what! 1) CORRELATIONAL Mistakes people make from correlational evidence: X= CHURCHES Y= BARS Z Correlational" Real cause" X = RACE Z Y = SAT SCORES More Examples: - Power lines - Breast feeding 2) CAUSAL (or sufficient ) 3) NECESSARY

7 So now, let s look at another EXAMPLE: What accounts for (causes) singing behavior in songbirds? - male birds sing in the spring and summer (during the mating season) Physiological Account: What are the neural underpinnings of this behavior? Two nuclei in the hypothalamus: caudal nucleus of the hyperstriatum ventrale (CNHV) robust nucleus of the archistriatum (RNA) Size of these two nuclei - males vs. female songbirds - sparrow and finches vs. chickens and pigeons Inject testosterone into a female, which increases the size of these two nuclei -> female starts to sing

8 Damage the nuclei -> Male birds don t sing (also Female birds will respond to all songs) Still Many Questions to Answer: e.g., How exactly does activity in these two nuclei produce motor activity that makes the bird sing a song? Functional Account: What is the function of this capacity? - Attract females to reproduce - Defend territory - use high pitch sounds

9 Ontogenetic Account: How does this capacity develop? - Male birds need to learn their song from other birds - Born in the Summer - Learn the song in the late Summer / early Fall - Sensitive Period: Between post-natal days But only start singing the next Spring! Evolutionary Account: How did the capacity evolve? Song birds that are close on the evolutionary tree have similar songs, will have some general acoustic features in common