The brain Flashcards
(98 cards)
Nervous system
Collects and responds to information. Coordinates organs including the brain
Nervous system subdivisions
CNS and PNS
PNS = ANS + SNS
ANS = sympathetic and parasympathetic
CNS= Brain and spinal cord
Central nervous system (CNS)
Right hemisphere controls left side of body and vice versa
Brain = conscious awareness and decision making.
Brain stem = automatic functions, some reflex responses and consciousness.
Peripheral nervous system (PNS)
information from outside world to CNS
Information from CNS to muscles
Autonomic nervous system (ANS)
Automatic functions eg. breathing, heart rate, stress response
Somatic nervous system (SNS)
Voluntary movement of muscles and reflex responses. Sends messages to muscles and takes in information from sensory organs.
ANS in depth
Homeostasis, an automatic system, sympathetic nervous system, parasympathetic nervous system
Homeostasis
Maintains a balanced internal state by monitoring activity of the body organs
Autonomic system
No conscious control because functions are vital to life
Sympathetic nervous system
psychological arousal, triggered when stressed and leads to fight or flight response.
Parasympathetic nervous system
opposite to sympathetic
Produces rest and digest response to return body to resting state.
Fight or flight response
Brain detects threat, Release of adrenaline, the response, Once the threat has passed.
Brain detects threat
hypothalamus identifies a threatening event (a stressor)
triggers the sympathetic division of the ANS to act
Release of adrenaline
ANS changes from parasympathetic rest state to aroused sympathetic state
Stress hormone adrenaline released into bloodstream
Flight or fight response
Immediate and automatic
Psychological changes due to action of adrenaline, e.g. increased heart rate, decreased digestion.
Gets body ready to confront threat (fight) or energy to run (flight)
Once the threat has passed
the parasympathetic division of ANS takes over, ‘rest and digest’.
James-lange theory of emotion
event –> arousal –> interpretation –> emotion
JL theory - psychological arousal first
Hypothalamus arouses sympathetic division of ANS.
Adrenaline released leading to psychological arousal (fight or flight)
JL theory - emotion afterwards
Brain interprets psychological activity
Causes emotion, e.g. love, fear.
JL theory- an example
Meet bear in forest
Sympathetic arousal: muscles tense, heart rate increases
Interpret as fear
JL theory - no physical changes = no emotion
Speaking in front of class, no increase in heart rate means you don’t experience any sense of fear.
JL evaluation 1
There is evidence that emotions do come after arousal in the case of phobias
JL evaluation 2
Challenged by the Cannon-Bard theory which argues that we experience emotions at the same time as psychological arousal. e.g. we feel embarrassed at the same time as we blush
JL evaluation 3
The two-factor theory suggests emotion may be more complex (Schacter and Singer 1962). We need social cues to determine the emotion (For example, your heart racing can be interpreted as fear if in a dark alley or as excitement if you’re kissing someone you like.)