Physiology and behaviour Flashcards
tinbergens 4 questions
-causation- ‘how’ does it happen
-function ‘why’ does it happen? (function in individuals (f) adaptive function in species (F)
-ontogeny- ‘how’ does it develop
-phylogeny- ‘how/when’ does it evolve
-we look at the ‘how’ for physiology
what behaviours if tinbergs questions do we look at for physiology
-we look at the ‘how’ for physiology
-immediate or proximate causation
-development (ontogeny)
what does behaviour involve
-behaviour involves a coordinated muscular response
-sensory system>nervous system> behaviour
-touch something hot>finger tip> neurons> brain> neurons> muscle remove your hand
peripheral nervous system
-simple reflexes- PNS
-nerves ganglia outside of brain/spinal cord (connects CNS to limbs/organs)
central nervous system
-complex behaviours- CNS
-much more protected (spinal collum/skull) so less damage
-often modulated by hormones (facilitate or inhibit a specific behaviour but dont cause it)
example of the interaction of physiology and behaviour
-high testosterone leads to increased aggression
-but
-losing a fight decreases testosterone production
the two physiological systems
-neural and sensory systems
-hormonal and pheromonal systems
characteristics of neural and sensory systems
-electrical
-fast acting
-central and peripheral nervous systems
characteristics of hormone and pheromonal systems
-chemical
-longer acting (ie. seasonal)
-target specific tissues
how are the hormone + pheromonal and and neural + sensory systems interconnected
-neural —> hormonal via hypothalamus
-pheromonal —> neural via sensory systems
neural connections and hypothalamus
-NS affects hormonal system via the hypothalamus
-hypothalamus is loacted deep in the brain (protection is important)
-functions:
-controls master glans (pituitary)
-2Hs homeostasis and hormones
-senses what is wring
where does the hypothalamus receive information from
-visceral sensory information form the vagus (blood pressure, gut digestion)
-information from the spinal cord (body temp)
-visual information (light/dark cycle)
-complex sensory information (smell, emotion)
how does the visceral sensory relay info form the vagus
blood pressure, gut digestion—nucleus of the solitary tract—hypothalamus—digestion
how is info from the spinal cord relayed
spinal cord—body temprature—brain stem reticular formation—hypothalamus—body temprature control
how is info from the visual information relayed
light/dark cycle—retina—hypothalamus—circadian rhythm
how is the info the complex sensory info relayed
smell, emotion—limbic and olfactory system—hypothalamus—feeding and reproduction
neural control of behaviour: simple reflexes
patellar, blink, swallow
neural control of behaviour: complex behaviours
courtship, nesting, feeding
properties of neural response:
1) initiation
2) coordination
-response inhibition
3) control
-latency, refractory period, homeostasis
initiation characteristics
-stimulus internal or external
-threshold and action potential (response)
-summation-temporal or spatial (weather or not enough to cause action)
-elec activity of neurons
-moving ions to reach state where membrane potential is depolized to initiate AP
-response to stimulus (neural responce must exceed threshold to initiate an AP
-all or nothing resonse
summation
-multiple inputs combine to initiate a response
-temp summation: stimulus is repeated overtime, single neuron rapid firing
-spatial summation: multiple site, multiple neurons sending signals
inhibition and coordination
-inhibition is necessary for coordination
-neural inhibition (walking opposing muscles are inhibited)
-behavioural inhibition
-can only do one thing at a time
-alternate bouts of feeding and drinking
homeostasis
-physiology and behaviour balance each other out to maintain homeostasis
-energy balance ( input and output/ growth and maintenance
models of homeostasis (closed system)
-closed loop systems
-feedback mechanisms: preforming the behaviour results in inhibition (-)
-examples:
-thermoregulation
-feeding
-drinking
homeostasis examples
-thermoregulation
-cold: leads to huddling, shivering
-heat: panting, wallowing, shade seeking, drinking
energy balance & hydration
-hunger: hunting, foraging
-thirst: seek water, drinking
thermoregulation physiological response
-cold exposure +
-thyrotropin-releasing hormone
-anterior pituitary+
-thyrotropin
-thyroid+
-thyroxine+
-thyroxine can send a negative feedback to anterior pituitary to slow process
hormones and connection to behaviour
-they dont cause behaviour
-they do initiate physiological actions which may be necessary for behaviour
-release could cause another hormone to be released
-or release could directly cause an organ to change behaviour
