BIOPSYCH INTRO
The nervous system is made up of:
● CNS (central nervous system)
● PNS (peripheral nervous system)
The central nervous system (CNS)
● Brain + spinal cord
🧠 The brain consists of:
● Cerebrum (4 lobes) - frontal lobe (speech, thought, learning), parietal lobe (sensory
info), temporal lobe (hearing, memory), occipital lobe (visual)
● Cerebellum - Control of motor skills/balance, if damaged problems arise in speech,
motor problems or epilepsy
● Diencephalon - Contains the thalamus (relays nerve impulses from senses to
brain), and the hypothalamus (regulates body temperature, hunger and thirst). Also
links the nervous system to the endocrine system in order to release hormones from
the pituitary gland
● Brain stem - Regulates breathing and heartbeat (automatic functions) 🫁🫀 Motor and
sensory neurons go through the brain stem which allows impulses to pass between
spinal cord and brain
🩻 The spinal cord:
● Relays messages between the brain and body to regulate processes + coordinate
voluntary movement
● Circuits of nerve cells perform involuntary reflex movement
● If an area of spine is damaged, nerves below the damage can be cut off and unable
to function
The peripheral nervous system (PNS)
● Consists of all other nerves outside of CNS
2 main divisions:
● Somatic nervous system (SNS) - Controls voluntary movement for muscular
skeletal system, receives info from sensory receptors (eg eyes, skin) 💪
● Autonomic nervous system (ANS) - Controls essential life-maintaining involuntary
processes (eg breathing, heartbeat, digestion). 🫁 Prepares body for fight/flight. ANS is
made up of the:
- Sympathetic nervous system - Fight/flight. 😟 Activated when threatened/aroused.
(Threat->amygdala activated->sends distress signal to hypothalamus->hypothalamus
activates the SAM pathway running to the adrenal medulla->adrenal medulla is
stimulated->secretes adrenaline and noradrenaline into bloodstream. Adrenaline =
faster heart rate, blood flow (=more blood to brain and muscles (=more oxygen)),
respiration (breathing), sweating to regulate temperature. Digestion stops bc is not an
essential process, bladder relaxes)
- Parasympathetic nervous system - Rest and digest. 😌 ACTH released. Deals with
normal body functioning. Relaxes body when threat has passed (slows down and
regulates heart rate, blood pressure, breathing + digestion starts again)
The nervous system is made up of:
● CNS (central nervous system)
● PNS (peripheral nervous system)
The central nervous system (CNS)
● Brain + spinal cord
🧠 The brain consists of:
● Cerebrum (4 lobes) - frontal lobe (speech, thought, learning), parietal lobe (sensory
info), temporal lobe (hearing, memory), occipital lobe (visual)
● Cerebellum - Control of motor skills/balance, if damaged problems arise in speech,
motor problems or epilepsy
● Diencephalon - Contains the thalamus (relays nerve impulses from senses to
brain), and the hypothalamus (regulates body temperature, hunger and thirst). Also
links the nervous system to the endocrine system in order to release hormones from
the pituitary gland
● Brain stem - Regulates breathing and heartbeat (automatic functions) 🫁🫀 Motor and
sensory neurons go through the brain stem which allows impulses to pass between
spinal cord and brain
🩻 The spinal cord:
● Relays messages between the brain and body to regulate processes + coordinate
voluntary movement
● Circuits of nerve cells perform involuntary reflex movement
● If an area of spine is damaged, nerves below the damage can be cut off and unable
to function
The peripheral nervous system (PNS)
● Consists of all other nerves outside of CNS
2 main divisions:
● Somatic nervous system (SNS) - Controls voluntary movement for muscular
skeletal system, receives info from sensory receptors (eg eyes, skin) 💪
● Autonomic nervous system (ANS) - Controls essential life-maintaining involuntary
processes (eg breathing, heartbeat, digestion). 🫁 Prepares body for fight/flight. ANS is
made up of the:
- Sympathetic nervous system - Fight/flight. 😟 Activated when threatened/aroused.
(Threat->amygdala activated->sends distress signal to hypothalamus->hypothalamus
activates the SAM pathway running to the adrenal medulla->adrenal medulla is
stimulated->secretes adrenaline and noradrenaline into bloodstream. Adrenaline =
faster heart rate, blood flow (=more blood to brain and muscles (=more oxygen)),
respiration (breathing), sweating to regulate temperature. Digestion stops bc is not an
essential process, bladder relaxes)
- Parasympathetic nervous system - Rest and digest. 😌 ACTH released. Deals with
normal body functioning. Relaxes body when threat has passed (slows down and
regulates heart rate, blood pressure, breathing + digestion starts again)
