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230 PSY 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 hypothalamus!! -has secretomotor neurons that send axons to the pituitary secretes hormones that control thirst, hunger, sexual motivation, and rage -lesions of the hypothalamus cause a loss of control over these behaviours **HYPOTHALAMUS** -controls activity in all three motor systems and receives all three corresponding inputs (somatomotor = voluntary = cerebral, autonomic visceromotor = reflex, neuroendocrine = state = neurotransmitters) -controls behaviours for ingestion, reproduction, and defense -to do this, neuroendocrine motor zone sends hormones that control thirst, hunger, sexual motivation, rage, thermoregulation, sleep/wake -responsible for the social behaviour of survival -rostral = goal-oriented behaviour = ingestive and social (reproductive and defensive) -caudal = exploratory and foraging behaviour (control orientation of eyes and body) receives input from the ventral tegmental area -receives triple descending projection from cerebral hemispheres -proposed that all part of cerebral hemisphere belong to either cerebral cortex or basal ganglia -hypothalamus receives input from virtually all part of the cerebral hemisphere -hypothalamic medial nuclei is at the top of the motor hierarchy and receives all three inputs **-ventromedial column of the hypothalamus forms the core of the behavioural control column at the top of the motor hierarchy *-divided into rostral (front) = goal-oriented behaviour = ingestive and social (reproduction and defense) behaviours *-caudal (rear) = exploratory and foraging behaviour responsible for orienting movement of the eyes, head, neck, and body for exploration essential for survival and establishing goals for survival -motivated behaviour has 3 phases = initiation, proucurement, and consummatory -view motivational systems in terms of the various classes of inputs that they receive (sensory, cognitive, state) different inputs allow for the initiation of different goals -motivated behaviour control column is at the apex of the motor system hierarchy *-cerebral hemispheres have three parts which generate a triple descending projection to the behavioural control column at the brain stem -cortex excitatory = glutamatergic (excitatory neurotransmitter) -striatum inhibitory = GABAergic (inhibitory neurotransmitter) -pallidum disinhibitory = GABAergic the cerebral hemispheres communicate with the motor system via these three connections to the hypothalamus at the apex of the motor control system in order to generate different responses -olfactory is the only sense that receives direct sensory input, not mediated by thalamus **-ventral tegmental area controls movement of head and neck and projects to the caudal part -triple descending model applies to all part of cerebral hemispheres but is differentiated in different regions -projections usually have multiple targets -cortex sends divergent input to striatum and pallidum has multiple targets within these regions -differentiations/specializations of the triple descending projection to the motor system associated with different regions - different regions control different pattern generators for different behaviours -limbic system = expression and elaboration of emotions (described by Broca) -medial cortex = part of limbic = what we feel -lateral neocortex = what we know -old brain = reflex and instinctive behaviours -new brain = connecting associations and elaborating anticipatory behaviour -basal ganglia and thalamocortical loop both send input to lower levels of the motor system A Few Degrees of Separation -all neurons in brains are linked by a small number of connections, but in reality the flow of information between neurons is selective -the number of possible connections is greater than the number of neurons because the dendrites branch to many other neurons -to map connection of neurons in an emotional state you need a behavioural task to elicit the specific emotion -fear conditioning is important in understanding fear behaviour -turns meaningless stimuli into warning signs and danger cues on the basis of past experience variation on classic conditioning (Pavlov) -*fear behaviour is inborn, a natural reflex therefore fear conditioning does not involve response learning because the response is inborn and can be activated by natural or learned triggers -fear conditioning occurs quickly -spontaneous receovery is seen in treating phobias -fear is good because we learn protection but bad because it can creep into the everyday and make us anxious -because humans have autonomic fear responses, fear responses have been used to study unconscious emotional processing in humans because it's autonomic and doesn't need to go through cognitive processing -presuming that there's a conscious state of fear is unnecessary conscious fear is a consequence not a cause of the conditioned fear response -typical fear response = freezing autonomic nervous system is activated and helps the freezing response by releasing stress hormones, suppress reactivity to pain, and reflexes are potentiated measure these bodily reactions as a measure of the conditioned fear response -limbic system is involved in emotion -to determine the pathway, start at the known starting point = auditory system go through auditory hierarchy and work downward until conditioning is affected -cortex has no effect but thalamus does -track by injecting tracer -signal flows from thalamus to amygdala -amygdala = small region in forebrain, used in emotion -conditioned fear bypasses the cortex and goes straight from the thalamus to the amygdala -**in amygdala is the central nucleus linked to the brain stem areas that control the autonomic responses of fear conditioning (responses are elicited by different projections from the amygdala to different regions of the brainstem) -**lateral nucleus of the amygdala receives info from the thalamus and transmits it to the central nucleus and then to the brainstem which elicits the response therefore the lateral and central regions of the amygdala are essential in fear conditioning -in conditioning involving 2 similar tones, info goes to cortex which can discriminate, the thalamus cannot -neurons from thalamus to cortex are narrowly tuned and discriminate whereas neurons from the thalamus to amygdala are broadly tuned -low primordial survival path which is shorter therefore for helpful survival, shorter because it uses less links -cortex is responsible for stopping the wrong response, not for providing the right response -contextual conditioning = incidental learning good for survival because it increases the number of danger cues you have -**hippocampus creates a representation of the context and is essential for contextual conditioning -pools all the stimuli together sends info to amygdala -amygdala is the hub of fear receives inputs from thalamus(low level input), cortex, and hippocampus (high level input) -the amygdala is therefore responsible for appraising the emotional significance -people with dominant thalamic or uncoupled cortical pathways may create emotional memories that don't coincide with perceptions of the cortex and therefore have poor insight into their emotions -uncoupled hippocampus = express inappropriate emotions -can't elicit fear if amygdala is damaged in mammals and non-mammals -damage to amygdala = can't turn stimuli into fear cues, can't read fear on people's faces -role of amygdala is same in most animals just controls diff sort of fear response -we have prepackaged involuntary response programmed to protect us -having cognition means we can plan our next response automatic response gives us time to decide on the next move turn reaction into action -prefrontal cortex makes new plans and weighs the consequences -damage to the frontal lobe = difficulty planning -prefrontal and basal ganglia link to amygdala and allow for emotional actions -bigger brains = better plans, but we pay the price of anxiety -emotional coping = cognitive planning once we're in the midst of an involuntary response -our reactions are affected by our genes, experience, and creativity A Model of the Limbic System and Basal Ganglia -together, limbic system and basal ganglia is responsible for behavioural function and information processing *it's a mechanism for the attainment of goals -limbic system controls sensory aspects of goal direction (recognizing and evaluating) -basal ganglia controls the motor aspects (establish and execute goal-directed motor programs -final goals are innate, develop sub-goals -set up series of linked sub-goals by forming associations between neutral stimuli and primary reinforcers etc. to make a plan that gets to the goal -once cue-reinforcer association has been established, animal can approach or avoid the cue **accomplished by transmitting signal from amygdala to basal ganglia -amygdala is associated with cue-reinforcer learning **nucleus accumbens is the interface between the limbic system and basal ganglia and releases dopamine in association with rewarded behaviour (rewards the frame) **nucleus accumbens uses info about cue-reinforcer relations to establish and run sequences of motor programs to get the goal (but doesn't contain info about the steps), motor steps are executed by the dorsal striatal system, switching to the next step of the program is triggered by a release of dopamine in the ventral tegmental area -**goal-monitoring comparator is mediated by the septohippocampal system and the Papez circuit -Papez loop makes predictions -comparison takes place in the subicular neurons make a match-mismatch decision (match = release of dopamine) *anxiety= activity in the behavioural inhibition system (BIS responds to threats of punishment and non-reward and novel stimuli output is behavioural inhibition, increased arousal and attention = anxiety -anti-anxiety drugs impair BIS so threats can't evoke anxious behaviour -neural substrate of anxiety must regulate activity in the BIS = septohippocampal system because it works to detect threat and novelty (because it acts as the predictor -symptoms of anxiety fall into three states = autonomic, behavioural, and cognitive *schizophrenia = structural disorganization in brain loss and abnormal packing of neurons -overreactivity in ascending dopaminergic path exacerbates psychotic symptoms -propose an abnormality in connection between basal ganglia and limbic system motor system fails to receives confirmatory messages therefore expected outcomes appear novel -or, abnormal connection between septohippocampal comparator and prefrontal cortex therefore expected outcomes appear novel -or lack of one dopamine pathway leads to overcompensation in another Goals and Behaviour -behaviour is a feedback process adjust behaviour to keep on track of goals -goal = goal behing a set of activities plan = subgoals and strategies to achieve your goal -people use strategies that fit with their style to achieve the same goals -self-concept = a goal in dynamics of behaviour -approach goals and avoidance goals -goals energize and direct behaviour and give meaning to life *-the self is composed partly of goals therefore, to understand someone you have to understand their goals -goals give tasks a particular meaning and influence how you approach them learning vs. performance goals -performance is better when a high goal is set but too high = don't adopt goal = lower performance -goals are organized in a hierarchy of abstraction and broken into subgoals that eventually become concrete actions *-feedback loops exist in the goal hierarchy high loops act to reset the reference value of the lower loops based on perception and actions the reference values therefore become more concrete and restricted the lowest level = performing a task hierarchy = system concept (ideal self guiding principles) principle control (principles and traits qualities) programs (course of action behaviour) sequences (automatic actions) motor control -enact programs using sequences (programs become sequences when they are automatized) -there are "be" (abstract), "do" (concrete) and "motor control goals" (physical movement) -lower goals can contribute to several higher goals -means-end analysis = end- higher goal, means lower goal -however, this implies conscious effort whereas the goal execution process is largely automatic (means-end can keep people on track in their daily lives) -*control at all levels is simultaneous all the lowest muscular acts are embedded and engaged in the abstract goal whenever one level is engaged, all levels beneath it are engaged -- can't separate abstract goals from their lowest physical responses -people identify actions at high or low levels of abstraction -naturally drift towards high abstraction as long as it can be maintained (until a difficulty crops up) -movement from low to high depends on an emergent property at the high level -people like to stick with a single abstract property won't switch -people at low levels are vulnerable to cues implying different directions impulsive, less stable -when people report on ideal self, usually list several facets of a unitary self -usually break down hoped-for-self goalds into qualities of principles ("be" goals, relating to higher abstraction on goal hierarchy) and programs ("do" goals, relating to lower, programs levels of hierarchy) -helpless children have performance goals and fail boast to compensate demonstrate how people can have the same intermediate goal but some are rigid (performance) and others view it dynamically (learning) -goals shape how you approach something -hierarchies are used in symbolic self-completion theory (regulate behaviour to conform to a specific ideal), positivie sense of self (regulate behaviour for a positive sense of self), terror management theory (hold on to a world view that allows access to symbolic immortality, avoid their own mortality) Development of Markers for the Big-Five factor Structure -want shorter test -alternative is the NEO-PI -use the large inventory clusters to evaluate the convergent validity of shorter tests -factor marker = generates a target structure when factor analyszed -personality scales = measures of individual differences -representative sampling of domain, uniform sampling, cluster sampling -cluster is best because you can ensure the same number of variables are selected and reduces discrepancies in reliabilities and will be more applicable and robust -easier to get univocal markers from unipolar scales (variables load on to the marker factor) vs. bipolar scales -organizing scales transparently made participants sensitive to the similarities therefore the loadings were more accurate -transparent is more univocal and has more within trait convergence and homogeneity within answers for the same marker however, prone to subject's giving higher selfratings -small sets can serve as markers of big 5 -unipolar scales are more robust across samples -hard to select same number of variables for each factor because big 5 are disproportionately represented in the lexicon (symptoms of neuroticism have no direct antonyms -when antonyms are presented unipolarly, they're not always considered antonyms -use a test with half antonyms pairs and half variables that map to the factors -test for reliability should elicit the same factors in descriptions of self and others -tested against NEO-PI and Hogan-PI and found to be congruent -shorter but still reliable the price of brevity is that it may not be a reliable marker for one or more factors -unipolar are more univocal but univocality can be maximized in bipolar scales using a transparent layout ... 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