Dichotic Listening Experiment

Dichotic Listening ExperimentGeorge PapamanolioudakisDichotic listeningAbstractIn this experiment we quiet entropy from seventeen (17) first y auricle psychology students in order to identify the contrarietys in expression realisation between the left field and the correct ear. base on previous findings we expect that on that point will be a signifi cleart difference between them, as the left hemisphere of the flair which controls the the pay off way situation of humans bodies, contains major arenas controlling speech producing and recognition (G everyese Stamenov, 2002). A dichotic show was produced, using headphones, presenting the participants nonsense syllables such(prenominal) as ka and ta at the same time to both left and right ear. Our goal was to give way scores from both ears and ratify if there would be a difference between them. The data we collected was ratio, within participants, and they were analyzed using a non-parametric test (Man-Whitney) due to th e small sample given. The results have sh receive that we can confirm the above meditation, although later research with higher sample, would help as finalize the findings, and provide disparateiate with diametric methods.IntroductionIn this study, we are leaving to examine whether peoples ability to cross words accurately, is affected by which ear they hear them in. In order to investigate this, we are going to perform a dichotic listening task. Previous research (Kimura, 1961) on this subject, showed that the left hemisphere deals speech sounds repair than the right. As the brain is connected with the body almost contra-lateral we assume that the right ear will be more capable of receiving words than the left. We can question this experiment, as it was performed to patients with epileptogenic foci, in different parts on the brain. Later on, based on an annual meeting of the academy of Aphasia in Chicago 1966, Doreen Kimura (1967) reviewed all endorse relating the asymmetr y in speech recognition between the cardinal hemispheres of the brain, confirming that the right ear of all humans was more able to recognize verbal stimuli due to dampen connections with the left hemisphere of the brain. an separate(prenominal) experiment (Molfese, Freeman, Palermo, 1975), which recorded auditory evoked responses from both cerebral hemispheres of humans in all ages, concord that the left hemisphere responded more dynamically in speech stimuli, than the right which responded better in non-speech stimulus. The undercoat that makes the left hemisphere more accurate in verbal speech stimuli, is that many theaters related to speech are located there. Variety of evidence can prove that, such as many trip studies of damaged brain cells on the left hemisphere of individuals that ca employ speech dysfunctions. More specific Brocas stadium among other areas of the left hemisphere, has been repeatedly reported to be very important in the verbal human race (Gallese S tamenov, 2002). All these studies would not be so accurate if scientists were not able to analyze brain drill through specialized technology such as Magnetic encephalography (MEG), functional magnetic resonance imaging and PET scans. Using FMRI scientists Embick, Marantz, Miyashita and ONeil (2000) concluded that Brocas area is specialized in the syntactic process of our brain, therefore there is a certain correlation given. Another area of the brain seems to play a crucial image on language understanding. Scientists found that when they increased the mean arterial pressure (pharmacologically) of a patient with a left frontal-temporal stroke, they managed to improve his language deficits as the Wernickes area (located on the left hemisphere) had improved perfusion (Hillis, et al., 2001) some other interesting findings have been discovered by examining patients with split brain. These patients had their school principal callosum removed (the part that unites the left with the rig ht hemisphere), for other medical reasons, and gave scientists the opportunity to explore the differences between the connected brain and the split brain. Those findings showed that in the split brain condition the individual could not identify verbally an object presented on his left eye only, (left eye right hemisphere) because there was no connection between the two hemispheres (Gazzaniga, 1967). many researchers have apply the dichotic listening test in order to examine whether the left or the right ear (right or the left hemisphere of the brain) would analyze better speech stimulus or other sounds (birds, music etc.). In this experiment we will introduce the same method in order to hang up with a conclusion, as we expect that there will be a significant difference between the left and the right ear.MethodParticipantsSeventeen first year undergraduate psychology students participated in this experiment. Ten (10) males and seven (7) females. Mean age =22.3, and the range was e ighteen (18) to twenty-nine (29). All participants were right handed. anatomyThe independent variable of this experiment was the left and the right ear, and the dependent was the correct identifications of the syllables provided both from the left and right ear. The experiment was within participants, as we measured correct answers from each participant individually.MaterialsEach participant used a pair of headphones which provided stimuli for each ear. The stimuli was 15 combination of nonsense syllables, consisted of one of a series of consonants (b, d, g, k. p, t) opposite with the vowel a. These sounds were recorded in 16 bit mono-aural mode and edited to 500 millisecond duration. Each person listened 30 presentations of the stimuli, carefully balanced for both ears, each one providing a different consonant vowel pairing. For example the sounds ka and ta were presented at the same time on a different ear. The presentation of the sounds was reversed for a total of 30 trials. For example the sounds ka and ta were presented in both ears equally. here is the link to the test (Dichotic Listening)ProcedureAll participants arrived on CityU on time. They were welcomed by the instructors and placed on their seats. They were asked to get hold of the information sheet and after all questions were answered they signed the consent form. Each participant used his/her own com modeler with her/his own headphones. They were asked to visit the link to the test, and when everyone was ready they completed the dichotic listening test individually. The test that was used was from APA webpage ( http//opl.apa.org/Experiments/AlphabetList.aspx) on the experiments section located under word d (for dichotic listening). After clicking in the test they were asked to put the class ID number in order to collect the data from each of them. After they finished, they were thanked for their participation in the study and left.ResultsThis experiment took place in order to confirm that t he right ear would recognise better syllables due to the immediate connection to the left hemisphere, than the left ear. The data we collected was ratio, within participants, and a non-parametric test was carried out (Man-Whitney) because of the small number of participants. The data shows that there was a significant difference understanding syllables from left and right ear. More specifically the right ear scored much higher (m=11,76 sd= 3,63) than the left (m=6,71 sd=3,08). The hypothesis was two tailed, and based on Man Whitneys non parametric test z=3,64 pDiscussionBased on previous research, we were able to perform a dichotic listening test in order to confirm that there would be a difference understanding syllables from right to left ear. As Doreen Kimura suggested (1961) the right ear was more capable recognising verbal stimulus as it is connected directly to the left hemisphere of the brain. arrogance which was made after many dichotic listening tests (Kimura, 1961), brain dysfunctions especially in the Brocas and the Wernickes area (Gallese Stamenov, 2002), and specialized brain scanning through MEG, FMRI and PET technology (Embick, Marantz, Miyashita ONeil, 2000). The absence of corpus callosum in many case studies confirmed that after separating the two hemispheres of the brain (split brain), the patients were not able to recognize verbally an object presented on their left eye, as the connection to the left hemisphere was lost (Gazzaniga, 1967).Our hypothesis was that there would be a significant difference understanding speech stimulus from the left to the right ear, and our findings can confirm those differences showing a huge possibility to find the same results to the whole universe of discourse pReferencesEmbick, D., Marantz, A., Miyashita, Y., ONeil, W., Sakai, K. L. (2000). A syntactic specialization for Brocas area. Proceedings of the National Academy of Sciences, 97(11), 6150-6154.Etard, O., Mellet, E., Papathanassiou, D., Benali, K. , Houd, O., Mazoyer, B., Tzourio-Mazoyer, N. (2000). Picture naming without Brocas and Wernickes area. Neuroreport, 11(3), 617-622.Gallese, V., Stamenov, M. (2002, April 1). reverberate Neurons and the Evolution of Brain and Language. Retrieved from ebscohost http//web.a.ebscohost.comGazzaniga, M. S. (1967). The split brain in man. Scientific American, 217(2), 24-29.Hillis, A. E., Barker, P. B., Beauchamp, N. J., Winters, B. D., Mirski, M., Wityk, R. J. (2001). Restoring blood pressure reperfused Wernickes area and improved language. Neurology, 56(5), 670-672.Kimura, D. (1961). Cerebral dominance and the perception of verbal stimuli. Canadian Journal of Psychology/Revue canadienne de psychologie, 15(3), 166.Kimura, D. (1967). functional asymmetry of the brain in dichotic listening. Cortex, 3(2), 163-178.Molfese, D. L., Freeman, R. B., Palermo, D. S. (1975). The ontogeny of brain lateralization for speech and nonspeech stimuli. Brain and language, 2, 356-368.