PSY 230 Test 1 Cerebral hemisphere regulation of motivated behaviour-consciousness is a product of activity of the cerebral hemispheres-voluntary control of behaviour is mediated by cerebral influences descending onto the sensorimotor nerves of the brainstem **-behaviour is therefore a product of activity in the motor system – it is just muscle contractions controlled by the somatic motorneurons-there are three types of inputs to the motor system: sensory (responsible for reflexes, go from senses to actions, involuntary reflexes we don’t have to think of), behavioural state (responsible for state control, inputs come from chemical feedback, ex. neurotransmitters, controls wakefulness and level of arousal and spontaneous activity), cognitive (voluntary control because we think about what we want to do and then send the message to the motor system)-each input maps onto its own set of motorneurons-motor system gets input – creates action = behaviour ***sensory systems have a dual projection – projects directly to the motor system (reflexes, needed for survival) and projects to the cerebral cortex where sensations and perceptions are processed and elaborated on – can use this info for voluntary actions on the environment-motor system is organized as a hierarchy-locomotor pattern controller in subthalamic locomotor region (master controller) – locomotor pattern initiator in mesenchephalic motor region (initiates blast off) – locomotor pattern generator in spinal chord (generates movements) – somatomotor neuron pools – locomotor behaviour **evidence from this hierarchy is seen when a paraplegic can walk on a moving treadmill – shows that movement patterns are mapped into our body and the patterns for movement reside in the spinal chord therefore, the hierarchy is a two-way street and input from the bottom (muscles moving) can make the locomotion happen-locomotor pattern controller generates spontaneous inputs and passes them down-no mesencephalic region in brain = no spontaneous movement because the hierarchy/chain is broken and the messages can’t get down to the motorneurons-somatomotor system = voluntary muscle-autonomic visceromotor system = smooth and cardiac muscle – involuntary-neuroendocrine secretomotor system = exerts influence via pituitary gland ***the hypothalamus coordinates the activity in all three motor systems = essential for survival (hypothalamic controller takes input from sensory, state, and cerebral and filters it down to the appropriate motor system)-can consider hypothalamus to be in the forebrain-**hypothalamus controls behaviours that are essential for the survival of individuals and the species = ingestion, reproduction, defense-animals with only hypothalamus are hyperactive, exploratory, can regulate body functions and defend themselves
-hypothalamus also controls thermoregulation and sleep/wake cycle and has higher control of the motor systems = crucial-**the neuroendocrine motor zone is the most characteristic feature of the
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