EXSS 380 1st EditionExam # 2 Study GuideInformation Processing and Memory- Sensory info from internal and external must be processed by CNS like info processed by a computer- Primarily focused on reaction time, there’s a delay between presentation of a stimulus and initiation of a response-Stages of Info Processing- Stimulus identification: sensory receptor sense change in environment that’s large enough to meet threshold to cause a reaction, info interpretedo Involves 2 substages=  Stimulus detection: stimulus detected, info transmitted, signal interpreted and inherent meaning determined Pattern recognition: most movements assoc with multiple stimuli so here the pattern is recognized and is essential for an appropriate response- Response selection: have info about the stimulus, decide what motor program to create; takes the longest in normal functioning processingo Influenced by environmental cues and time required is dependent on=  Number of stimulus-response alternatives Hick’s Law As the # of response alternatives increase so does the choice RT, time required to pick response is linearly related to the amount of info that must be processed in making choice Exception to the Law occurs with practice, the more familiar you are with a task the shorter choice RT becomes Stimulus- response compatibility: motor function to stimulus is easy to give- Response initiation/programming: stimulate/prime area on primary motor cortexto initiate the motor responseo Can’t start until the other 2 stages are completedo Most voluntary response are complex and retrieved from motor memory, feedforward in natureo In classical experiment conducted by Henry and Rogers they gave people 3 tasks with increasing complexityo Were measuring time it took for individuals to remove finger from key (first step of each task) so stimulus ID and response selection didn’t change (told subjects what to do)- Because you synapse more neurons in complex responses they saw that the RT were longer for more complex tasks suggesting increase in necessary time to program the responseo Example: approaching traffic lighto Stimulus ID: recognition of light color change (green to yellow)o Response selection: decided whether to stop or go (influenced by factors like current speed, closeness of trailing car, and quality of breaks)o Response programming: activate lower extremity muscles to either press brake or gas- Explain how introduction complexity at each stage can alter info processing- Donder’s Subtractive Methos using 3 tasks to increase complexityo Simple Reaction Time (press key with R index finger when see light stimulus)o Go/No-go Reaction Time: red light means go and blue light means no go  modifies Stimulus IDo Choice Reaction Time: red light raise R hand and blue light raise L hand- Increasing the choice or stimulus causes an increase in reaction time because there are more stages of processing involved- Serial processing: info is processed in sequential order- Parallel processing: info processed simultaneously- The processes of Donder’s occur in series and parallel- Key Parts of Memory: Storing Info, Recalling Info, and Reproducing Movement- What are the problems with multiple theories on memories?- Descartes’ Dualism: body and brain are intertwined, soul and body- Reductionism: EVERY memory we have is two neurons hooking up at a synapse to create a connection- Neodualism: mind is emergent property of body rather than an independent entity, can’t be reduced to particular neurons and synapses- Understand early memory studies- Pierre Paul Broca had damage to left frontal lobe that produced language deficits- Wilder Penfield stimulated areas of the brain and elicited experimental memorieswhen he stimulated the temporal lobe- Dr. Brenda Miller studied H.M. a 27 yr old who had temporal lobe seizures. By removing his hippocampus she controlled the seizures but there was some memory loss. His long term memory and very short term memory was good but he had trouble transferring from short term to long term. His IQ and language stayed the same.o From this we learned that injury to the temporal lobe doesn’t affect all memory equally - Priming: recall improved with prior exposure by raising membrane potential of neurons you want to fire- Memory is reflexive rather than reflective in some instances because HM could complete puzzle faster with practice but didn’t remember completing it before- 2 phenomena classified as memory: storing trace of an event some time after it ends (seeing scar from fall as trace of an event) and active memory retrieval (recalling events that lead to the scar)- Understand the difference in the types of memory and be able to give examples- Types of Memory=- Declarative: memories of what, events, objects, people, etc.o Ex: Abe Lincoln was assassinated.- Non-declarative: memories of how, motor skills, habits, conditioned reflexes, etc. o ex: remembering when/how you learned Abe Lincoln was assassinated, learning to kick a ball, remembering how you cut your finger- Short-term memory: sensory memory, working memory- Long-term memory: declarative explicit memory, events (episodic memory), and facts (semantic memory)- If you retrieve something from long term memory, it’s moved to shorter term memory and then a response is created- If sense a stimulus, either repeat it to keep it in short term memory and then a motor response or put it in long term memory- Memory not simply in one place in the brain- Also, it’s commonly believed that motor memories reside in synapses but that’s inefficient because would only allow a finite number of memories- Memory of a computer is organized sequentially and need to know exact locationto access memory. VERY different from how our memory works (distributed and retrieved based on content)- Distributed memory: synapses and neurons have multiple memories associated with them and depending on how you move info across them you pull up different memories, like hologram- Plasticity: flexibility and may contribute to motor learning and adaptation to injury- Cerebellum may be neuronal learning site and may store long-term memorySensory Contributions to Motor Control- Understand the difference in feedback and feedforward systems influence on motor control- Closed loop (feedback) systems: sensory input (feedback) processed to generate or refine movement commands, CNS changes output based on sensory inputo Ex: homeostasis or