Biological Level of Analysis

Annotations:

• evolution plays a key role in behavior

1. mirror neurons
   1. Gallese et al. 1996

      Annotations:

      • isolate neural response in rhesus monkeys reaching for food When another individual reached for food, the neural response was still seen in the monkeys even though they weren't reaching for food
2. inheritance

   Annotations:

   • Genes and DNA are passed from parents to offspring
   1. twin studies
      1. Minnesota Twin Study - Bouchard et al. 1990

         Annotations:

         • Compared MZA's (monozygotic raised apart) and MZT's (monozygotic raised together) Cross-cultural validity - global study determines heritability estimate of 70% for intelligence
   2. intelligence
      1. Bouchard and McGue 1981

         Annotations:

         • Found that closer the kinship, the higher the correlation for IQ --- individuals 100% genetic relationship but different nurture = any IQ similarity will be genetics
3. Darwin & natural selection
   1. hormones
      1. oxytocin

         Annotations:

         • creates bonding within families and society -- evolutionary strength in community
      2. adrenaline

         Annotations:

         • causes flight/fight response  -- evolutionary survival
   2. disgust

1. Martinez and Kesner 1991
2. humans share 93% of genes with rhesus monkeys
3. Gallese et al. 1996

1. neurotransmission

   Annotations:

   • method by which messages are sent throughout the body --- cause body to respond to stimuli
   • neuron - nerve cell axon - body of neuron neurotransmitters - cross synapses, stored in terminal buttons synapse - gab between neurons dendrites - receive information
   1. acetylcholine

      Annotations:

      • muscle contraction
      1. Martinez and Kesner 1991

         Annotations:

         • Aim: determine role of acetylcholine in memory rats were trained to go through a maze, some given shots to block acetylcholine Findings: acetylcholine important role in creating memory of maze
   2. dopamine

      Annotations:

      • voluntary movement, learning, and feelings of pleasure --- excess = schizophrenia
   3. norepinephrine

      Annotations:

      • arousal, alertness, and stimulation of the sympathetic nervous system
   4. serotonin

      Annotations:

      • sleep, arousal levels, and emotion
      1. Kasamatsu and Hirai 1999

         Annotations:

         • aim: how sensory deprivation affects the brain serotonin levels increased in monks' brains -- sensory deprivation triggered release of serotonin
2. hormones
   1. oxytocin

      Annotations:

      • mother-child attachment -- secreted by pituitary and hypothalamus
   2. adrenaline
   3. cortisol
   4. testosterone & oestrogen
   5. melatonin

      Annotations:

      • SAD - seasonal affective disorder individuals are sleepy and lethargic because of an increase in melatonin --- genetically based explanation for behavior