Free Research Paper on Cognitive Psychology:
Cognitive psychology is said to be the branch of psychology that investigates internal mental processes and covers memory, reading, problem solving, etc. This research paper will discuss two aspects of cognition, visual attention and language processing, as well as explain how psychologists seek to understand them through such research methods as computational modeling and neuropsychological case studies. The objective of this paper is to show the evidence that cognitive processes cannot be ‘seen’ directly, but should be investigated through the series of research methods that are to b compared and adequately interpreted.
2. Visual attention
Attention and visual attention in particular is a very complex issue in psychology and it consists of the following key components: the selection of the object of interest in the area of interest, the selection of feature dimensions and values of interest, information flow control through the network of neurons, which form visual system and finally the shift from one object of interest to the other in time. The system of visual attention can be classified in accordance with various aspects. From the point of view of the stimulus, it can attract the attention by exogenous and endogenous methods. Exogenous components are predominantly defined by external stimulus characteristics, while endogenous mainly depend on the intentions and actions of the subject. From the standpoint of the subject, it can actually switch the fixation point of the gaze to the point being attended (Ward, 2004).
Computational models provide the basis for specifications of theoretical assumptions, as well as examination of their complex interactions by means of stimulation. In the ideal situations, models assist in explanation of the existing data and provide with predictions, which serve as a guidance for the further research.
The first plausible computational model for visual attention control was proposed by Koch and Ullman in 1985. Their model was centered on a ‘saliency map’, which is said to be an explicit two-dimensional map that encodes conspicuity of saliency or stimuli, at each place in the visual scene. The saliency map obtains inputs from early visual processing, and ensures the effective strategy control in which the attention focus just scans the saliency map in order of diminishing saliency (Koch & Ullman, 1985). On the basis of this computational architectural model, it is possible to illustrate five important components of any bottom-up attention model. These include the pre-attentive computation of early visual features across the total visual scene, integration of them to output a single control command of attention, the generation of scan paths of attention, the interaction between overt and covert deployment of attention, eye movements, and the interaction between scene understanding and factual attention (Wright, 1999).
Being just a computational hypothesis, the concept that saliency can be explicitly encoded by special cortex neurons has also obtained experimental support from many electrophysiological case studies.
Speaking about neuropsychological case studies in relation to visual attention the backbone of neuropsychological assessment should be mentioned Wechsler Adult Intelligence Scale (WAIS). This test can be supplemented by many additional tests, such as Wisconsin Card Sorting Task and verbal fluency, for instance (Parker & Crawford, 1992). WAIS was invented in the early 50s and was not the neuropsychological assessment instrument at first.
In the sphere of visual attention, two subtests from the list have been viewed as good measures of this functioning aspect. The Block Design task demands from the person to construct designs from blocks that have by turn colored faces. This demands a fair degree of strategizing and planning, in particular for the harder items. It is generally considered to be sensitive to frontal lobe lesions.
Cognitive deficits may be brought to bear on issues of regular cognition only through what is called task dissociation logic. From this standpoint, cognitive neuropsychology is said to be the method for drawing inferences of the form, “Task A and task B include different processing mechanisms”. The method is implemented by testing patients on multiple tasks, and further interpreting of the observed dissociations and associations of deficits in accordance with particular principles.
In case with single dissociations, it is finding of impaired performance on one task with normal performance on another suggests that the tasks differentiate in several of their processing mechanisms. Furthermore, this results pattern – a single dissociation – does not compose valid evidence for various processing mechanisms; the other interpretation is that both tasks need the same processing mechanisms, but one task requires more from these mechanisms than the other, and therefore reveals greater impairment when the mechanisms are endamaged (Shallice, 1988; Wright, 1998).
For the reason that single dissociations are tightly connected with this potential resource artifact interpretation (Shallice, 1988), stronger evidence is required to ensure a strong conclusion that two tasks differentiate in underlying processing mechanisms. Particularly, double dissociation is needed, in which one or more patients reveal poor performance on task A with good performance on task B, when one or more other patients reveal good performance on task A with poor performance on task B. Double dissociation excludes resource artifact interpretations. For the proper interpretation of the A-good-B-poor dissociation in terms of resource artifacts it is essential to assume that task B places stronger requirements than task A on the needed processing mechanisms; in order to interpret the complementary A poor- B-good dissociation it is necessary to make the contradictory assumption that task A requires more than task B from the mechanisms.
Another test is said to be the Digit Symbol task, in which the person is confronted by a number grid, with numbers from 1 to 9 alongside a diversity of symbols. Below it is a sequence of numbered boxes that is longer. The task is to copy the right symbol from the grid above into the box near the number in the lower grid. The person is given just two minutes to copy as many symbols as he/she can. This test is aiming to reveal the capability to hold concentration during the task period. Like all WAIS subtests, poor performance is also acceptable and can be explained by different factors. In relation to this, interpretation of the results demands experience and bringing together different information sources. For instance, the Digit Symbol subtask also is governed by good manual dexterity.
Memory can also be involved. There are some test versions that assist in the interpretation of the test results. Experienced clinicians do not completely rely on the results of the WAIS test to evaluate the visual attention of the patient, but also review the case history of the patient, along the observation of the patient’s performance during the whole testing session (Wright, 1999; Treisman & Gelade, 1980).
3. Language Processing
Language processing generally refers to how human beings process writing and speech, as well as understand that as a language.
Speaking about the computational modeling of the language processing, the TRACE model has the greatest depth and breadth of any other model (Martin, 2003). The TRACE model of speech perception is based on the interactive activation principles and information processing takes place by means of inhibitory and excitatory interactions of a big number of simple processing units, and each of them is functioning constantly to its own activation based on the activations of other connected unites. There are two simulation programs of this model. The first one deals with short segments of the speech. And the second one simulates the large number of lexical information for the phonemes identification and takes into consideration the fact that lexical effects can be found under definite conditions (McClelland & Elman, 1986).
The TRACE model also depicts how phonological constraints model can be encapsulated in definite lexical items, but still can be utilized to impact processing of non-word utterances. It also portrays categorical perception and the capability to trade cues off against each other in the identification of phoneme. In other words, it contains the main positive feature of Marslen-Wilson COHORT model that reveals immediate information sensitivity (Martin, 2003).
Speaking about neurological organization of the language processing by human being, it is essential to review the studies of language disorders.
Caramazza in 1990 suggested that beyond the common support for modularity, physiological information can be additional to the psycholinguistic consideration of normal people in specific information provision regarding receptive language processing. Two such rationale from aphasia are being reviewed: first, the statement that the agrammatic aphasic patients performance provides assistance for language processing model in which the closed-class vocabulary plays a central and distinct role in processing of sentences; and, second, a proposition that the receptive language function of certain agrammatic patients provides assistance for a two-stage model of sentence processing (Caramazza, 1990). And then again the author continues to disclose the importance of the pathology in the neuropsychological case studies of language processing claiming that neuropsychological information can be of three main types: selective preservation, selective loss, and exposed encoding. If brain damage can in some situations render a subject that is not capable of performing mental operation X, which is referred as selective loss, but capable of performing operation Y, which is selective preservation, then this dissociation between X and Y presumes that they can be carried out by functionally distinct mechanisms, particularly if one also reveals the converse dissociation: capacity to perform X but not Y. In fact, if the output of the preserved subcomponent would generally be subject to continuous processing by the impaired subcomponent, then the loss of these continuous operations can provide us with a window on the functioning of the preserved subcomponent, which is referred to as exposed encoding.
As to the patients with excessive aphasia or aggramatism, I would like to provide an example of the patient who came to the hospital and was trying to explain how he got there. His speech was not understandable and consisted of separate almost incoherent words. In the most difficult cases, the patient may just say the single word. There are cases when patients can forget words, for instance numbers, etc.
Phonemic, phonetic, lexical-phonological, and semantic representations are said to be involved in recognition of words, and disruptions at any levels can lead to word comprehension deficits.
Patients that are labeled as “pure word deaf” can ensure evidence that various systems are used in speech and non-speech auditory perception, as they have difficulties in perceiving speech but can hear music and sounds from the environment. Few researchers have proposed some evidence that deficit of those patients is not at the phonemic or lexical level, but rather at the level of acoustic cues to speech extraction. In other words, they have difficulties in perceiving fast changes in complicated pitch patterns that influence the speech perception more than other common sounds.
According to this point of view, these patients have hardships discriminating non-speech sounds, which are dependant on perceiving fast temporal changes (Poeppel, 2001).
Pure word deaf patients often have superior temporal lobe bilateral lesions, but some have unilateral lesions, which have been situated to the left hemisphere. The bilateral lesions suggest that both hemispheres are used in the extraction of phonetic cues to speech. The unilateral lesions have also been considered to be consistent with bilateral processing as these lesions commonly contain deep sub-cortical structures and therefore can do harm to both phonetic processing on the left side and reverse the outcomes of this processing on the right side from lexical phonological representations on the left side (Ward, 2004).
Phonetic cues are said to be mapped into phonemes. Some researchers have argued, nevertheless, that phonetic features are mapped immediately onto lexical representations, and therefore a phonemic level is not required. Factually, it comes out to be that no cases have been reported that reveal the pattern predicted from a deficit to the phonemic level, which is consonant perception and impaired vowel but sustained non-speech stimuli perception with acoustic features alike to those in speech. On the contrast evidence lack for a phonemic level, there is evidence that provides the support of the lexical phonological level distinct from semantics (Lehrnert et al., 1982).
Visual attention and language processing are essential aspects of cognitive psychology. Psychologists can understand them through the series of methods, in particular by computational modeling and neuropsychological case studies. Both methods are effective though have different approaches to the matter. Neuropsychological case studies seek to access the needed aspect of cognition through investigation of the possible disorders, and computational models provide the means for specifying theoretical assumptions and examination of their complex interaction through simulation.
It is impossible to perceive and evaluate cognitive processes directly, they can be observed through evidence, experiments and research form difference resources of information.Free research paper samples and term paper examples available online are plagiarized. They cannot be used as your own paper, even a part of it. You can order a high-quality custom research paper on your topic from expert writers:
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