Biopsychology Flashcards
The central nervous system
Made up of the brain and spinal cord
The spinal cord function
The spinal cord transmits messages from and to the brain
The nervous system
Made up of the central nervous system (CNS)
And
The peripheral nervous system (PNS)
The Peripheral nervous system (PNS)
relays messages from the environment to the CNS, via sensory neurons, and from the CNS to effectors, via motor neurones.
Subdivided into the autonomic nervous system and the somatic nervous system
The autonomic nervous system
Controls involuntary, vital functions of the body, such as maintaining heart rates and breathing rate.
The somatic nervous system
receives information from sensory receptors belonging to each of the 5 senses, and results in effectors being stimulated by the CNS, via motor neurones
The parasympathetic and sympathetic branches
These branches work as part of an antagonistic pair during the ‘rest and digest’ response, and are crucial in producing the physiological arousal needed to maintain the fight or flight response.
The sympathetic nervous system
the sympathetic nervous system increases heart rates, breathing rate, causes vasoconstriction and pupil dilation,
The parasympathetic nervous system
whilst the parasympathetic nervous system decreases heart rate, breathing rates, causes vasodilation and pupil constriction.
The endocrine system
The main chemical messenger system of the body, where hormones are secreted into the bloodstream from glands, and then are transported towards target cells in the blood, with complementary receptors.
The thyroid gland
the thyroid releases the hormone thyroxine, which increases heart rate and therefore increases the rate of growth.
The Adrenal gland
The adrenal gland releases adrenaline which creates the physiological arousal preceding the fight or flight response, through increasing the activity within the sympathetic branch of the nervous system.
The fight or flight response
The fight or flight response:
1.The body senses and becomes aware of a stressor in the environment e.g. the sound of a speeding car.
- Through sensory receptors and sensory neurones in the PNS, this information is sent to the hypothalamus in the brain which coordinates a response and triggers increased levels of activity in the sympathetic branch of the ANS.
- Adrenaline is released from the adrenal medulla in the adrenal glands, and is transported to target effectors, via the blood and through the action of the endocrine system.
- This results in the rectum contracting, saliva production being inhibited and a greater breathing rate. This creates the physiological response needed to sustain the fight or flight response, whose adaptive purpose is to enable us to escape the stressor and so increase the likelihood of our survival.
- Once the stressor is no longer a threat, as part of an antagonistic pairing, the hypothalamus triggers less activity in the sympathetic branch and more activity in the parasympathetic branch of the ANS. This is also referred to as the rest and digest response, due to the parasympathetic branch decreasing the activity which was originally increased through the action of the sympathetic branch.
Synaptic transmission
Synaptic transmission is a method of neurons communicating with each other, relaying information to the CNS across sensory neurons and carrying out responses dictated by the brain through sending information to effectors via motor neurons
Inhibitory neurotransmitters
Synaptic transmission is a method of neurons communicating with each other, relaying information to the CNS across sensory neurons and carrying out responses dictated by the brain through sending information to effectors via motor neurons
