Questions of the Neurophysiology of Learning and Memory - Essay Example

Running Head: EXAM PAPER Exam Paper Name Institution Date Qn. 1 The role of the US (reinforcer) in learning changed with the rise and fall of S-R learning theory The accepted assumption states that whatever is done in classroom is as a result of the understanding of the nature of children and how they learn. There are three main types of theories prevalent in classroom learning .these include learning as a form of mental discipline, due to the response to stimulus and learning as a form of cognitive interactions. In the avoidance learning, there is warning signal which is followed by aversive outcome, the unconditioned stimulus. Though there have been attempts to find the mechanism that leads to avoidance learning, only two theories, both the theory of stimulus response and the cognitive theory (avoidance) are yet to be experimentally compared. Changes in stimulus response do affect the habit strengths in that when the stimulus response is high the unconditioned stimulus becomes more effective and strong while the reduction in stimulus response could lead to slow, hence delayed response of the unconditioned stimulus (Bolles, 1975). Qn. 2. How retention of information in long term memory is achieved. With reference to theories and experimental evidence Memory can be referred to as the ability to recall information. Chemical reactions within the brain encode the information from the environment hence memory is formed. Long term memory can be termed as the memory that the subconscious mind stores for decades and which results from correct triggering from the stimulus. It is caused by motivations and positive experiences without emotional blocks and trauma. The long term memory works through the processes of coding, storage and retrieval with the information getting permanently stored in the brain’s prefrontal lobe, the cortex. The brain has over 100 billion neurons that feed it with the information not only from within the body but also from the environment. Scientists, psychologists and researchers have always been puzzled by how the brain stores long term information. Some theories and models that try to explain this include: The Atkinson-Shiffrin model Also referred to as the multi- store model, was formed in 1968 by Atkinson and Shiffrin and it suggests that the information can only be stored for a long time through rehearsal, that the permanent storage is due to multiple subcomponents and also portraying that both memory stores and sensory have single unit stores . It was criticized for being very simple. A diagram illustrating the Atkinson-Shiffril model The working memory model The memory has three basic stores which are the central executive, the visual-spatial sketchpad, episodic buffer and the phonological loop. The central executive is the attentive store, supplying information to the other three processes. Phonological loop is responsible for storage of auditory information by silent articulatory process e.g. repetition of mobile number continuously, hence leading to remembrance of short list of information.Visuospatial sketchpad stores spatial and visual data when tasks related to space(e.g. comparing distances) and sight(e.g. imagining images) are involved . Episodic buffer is responsible for connecting all the information and coming up with integrated units for the verbal, visual and spatial information as well as doing chronological ordering. Although it explains several practical observations like the reasons why two different tasks(verbal and visual) can be done more easily than two tasks that are similar(for example two visuals),and the effects of the length of words, the central executive concept has faced criticism as vague and also inadequate. A diagram illustrating the working memory model Currently memory is being attributed to the process that takes place at the molecular level where new proteins are formed in the translation process which are responsible for subsequently stabilizing any changes in the memory. This means that new memories get well represented in the brain (Dr Sandhi, 2000). A diagram showing the various processes involved in storing of information in the long-term memory. However, Aryeh Routtenberg, a neuroscientist, has completely changed the perspective on memory storage by claiming that the dynamic meta-stable process is responsible for memory maintenance and it is not the formation of new memories responsible for this as from the above view. This theory claims that permanent memory comes as a result of the process of memory re-duplication in the different networks of the brain. It further gives an example of a person’s name which is represented in several neural circuits hence becomes hard to forget. The components are malleable as well as transient, and since the neural networks don’t last forever, forgetting one’s name is inevitable. This kind of storage mechanism is most flexible hence enhancing quick retrieval of even elements that are not frequently retrieved, hence having greater benefits over other permanent storage models. The long term memory is caused by the rapid transformation of the protein shape present at the learning-activated synapses. Even though there is universal agreement that proteins are crucial for the storage of information in the memory, this hypothesis challenges the long-held idea that, for the stabilization of long term memory to be attained, the proteins that are newly synthesized must be delivered to the freshly activated synapses. However, generally the brain uses the coordination of the processes of retrieval, encoding, and storage for memory storage. Encoding determines how the brain keeps the memories. The hippocampus and frontal cortex decide whether the information is worth storing after analyzing it from senses. Hypothalamus is involved in declarative (information that can be put in to words) and spatial memory (describes a person’s location in space). The amigdala records emotional and stressful cases. The neurons produce electric signals and communicate as synapses. They amplify signals hence giving cell communication an advantage. The diagram below illustrates the processes (Dr Sandhi, 2000). Qn. 3. An account of the development of theories of the biopsychology of emotion The expression of emotions in man and animals’ was the first greatest event in studying the biological reasons for the occurrence of emotions. This piece of work was done by Charles Darwin. His idea was that emotions evolved right from the behaviours indicating the next action an animal would take in the given situation. James-Lange theory was the first theory that tried to offer an explanation on physiological reasons for emotions .It was the work of William James (1884) and Carl Lange (1885). It attempted to explain reasons behind the emotional occurrences and suggested that in case of an event, the body responds first before the emotions. The stimulus from the environment provokes bodily changes leading to the perception of the changes as emotions within the brain. The brain receives and interprets the stimulus that causes the emotions hence triggering the changes in the abdominal organs or the organs in the thorax. Due to these changes the emotional experience is triggered (Wickens, 2005). Canon-Bard theory was formulated by Philip Bard and Walter Cannon. It suggests that the emotional stimuli does evoke visceral as well as emotional responses and are completely independent of each other. However these theories are not fully correct since in some cases the emotions are triggered by stimuli that won’t produce visceral as well as peripheral response, for example patients with transaction of the spinal cord. Even with the absence of any eliciting stimuli, visceral responses still may frequently produce emotional state for instance a fast heart beat as well as increased respiration may lead to a feeling of fear even with the absence of the eliciting stimuli. Papez’s proposal followed the hypothalamus theory. This suggested that the limbic system controlled emotional expressions due to connections to hypothalamus and linked that to the cortex for emotional perception. This theory had the backing of cluver-bucy syndrome, a rare neurological disorder affecting the cerebral part of the brain (damage to a part of limbic system or amygdala damage).these patients were exploring objects using their mouth, hypersexual, fearless, and placid and with visual distraction. The schater-singer theory was formed by Stanly Schater and Jerome Singer. The theory suggests that for emotional experiences to come about, emotional arousal as well as cognitive activity have to be considered which aid in proper identification of the emotions. They concluded that despite the facts that individuals are aware of the causes of their emotional arousal, if no good reason is available, they will look for clues from their environment to assist them in interpreting the emotions. Even with the extensive research on this theory, experiments support this partially. Arousal theory has been proposed by many researchers, claiming that the behaviours do change due to arousal. The suggestion is that performance will increase with increase in arousal, however if the arousal exceeds given limit the performance decreases, this phenomenon is referred to as Yerkes-Dodson law. According to this, a little anxiety can improve performance (e.g. enhancing thorough preparation), but if it is severe it can impair the performance (e.g. Intense stage fright).however, this theory has not been fully supported by researchers especially on complex tasks. Qn.4. Factors that might influence the accuracy of eyewitness identification Stable eyewitness characteristics These are features of the eye witnesses that are not alterable, like the demographic characteristics. They include: Sex-the meta analysis of Shapiro and penrod points out that females are slightly likely to make correct identification only that their correct identification improvement are hindered by high level of false identification. According to the research the chances of making false identification are d=0.08 compared to the chances of making the correct identification which is d= 0.10. Race-race factor also contributes to the accuracy of eye witness identification. According to the research carried out by Platz and Hosch.According to the study carried out on the clerks of goods store with anglo, Mexican-american and black ethnicity, the average accuracy identification was 42.6%, 54.5% and 38.1%correct. Even though the blacks were more successful than others in their identification, the group did not differ in their number of false identifications (Davis, 2010). Intelligence According to Howells, 1938, the study research found out the link between intelligence and accuracy in facial identification accuracy. People with great verbal ability have also high chances of correct identifications. Age A lot of studies have tried to unveil the link between development and accurate identification with some positive results to show. According to the study of early stages, most of children developed accuracy in identification with age. In the kindergarten level, the correct identification ranges from 35-40%, the ages of 6-8 years have 50-58% correctness and 12-14 years have 70-80% correct eyewitness identification. In the same studies, false identification was found to reduce with age increase. Malleable eye witness characteristics Expectation of future identification test When confronted with the probability of requirement of the accurate identification, especially in legal matters, people always prove to be more accurate. Work conditions like requirement of identification of strangers and robbers always enhances and prepare clerks and bank workers to be very accurate in their identification. Training Training has always improved the accuracy of facial identification. If people are taught how to differentiate and categories different facial features, they tend to improve their skills of hence recognition and accurate identification. Drugs and Alcohol intoxication Drugs do have severe effects on their victims, including hallucinations. When people are under the influence of drugs they can make false claims and stick to that. They hardly remember past occurrences since their memory is also affected. This is also the case with people who always use alcohol excessively. Their vision is always affected hence they cannot be able to view their surrounding accuratey.Generally drugs affect the ability to have accurate eye witness identification. Poor health If a person’s medical health is poor, the person looses concentration due to the pains or fatigue. Severe cases could lead to failure in attention as well as memory. The health problems may be physical or emotional. Thoughts People whose thoughts are not concentrated on the real issue at hand but rather on other issues rarely recognizes actions around them or people next to them hence they can’t. This is so true with people who are faced with decision problems or multiple problems. Related threats and personal issues Eye witnesses might also hide information due to perceived consequences that may result from the disclosure of information, e.g threats, and fear of loosing an individual or even personal choice not to give the information. References Bolles, R.C. (1975). Learning Theory, Holt Rinehart Winston, Chap 1-8. Dr Sandhi, P. (2000). Long Term Memry: Behavioural & Cognitive Neuroscience Wickens, A (2005) Foundations of Biopsychology: Behavioural & Cognitive Neuroscience (2nd ed) Chap 5 Davis, J. (2010). Behavioural and Cognitive Neuroscience: Everyday Memory 2: Eyewitness Testimony. Read More