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    Ahlâkî uzaklaşma ölçeğinin Türkçeye uyarlanması
    (2016) Yalçın, Meral Gezici; Şenyurt, Ahmet Yasin; Gültepe, Bedirhan; Coşkun, Hamit
    Bu çalışmanın amacı Ahlâkî Uzaklaşma Ölçeği'nin (Moral Disengagement Scale) Türkçe uyarlamasını yapmak ve psikometrik özelliklerini incelemektir. Bu amaçla Bandura ve arkadaşları (1996) tarafından geliştirilen ölçek, 285 üniversite öğrencisine (194 kadın, 91 erkek) uygulanmıştır. Ölçeğin yapı geçerliğinin belirlenmesi amacıyla doğrulayıcı faktör analizi yapılmıştır. Ölçeğin güvenirliği, Cronbach alfa katsayısı ve iki-yarım güvenirliği ile hesaplanmıştır. Ölçeğin Türkçe formunun orijinal ölçek gibi tek faktörlü bir yapıya sahip olduğu ve uyum göstergelerinin yeterli düzeyde olduğu bulunmuştur. Ölçeğin Cronbach Alpha katsayısı .86 ve iki-yarım güvenirliği .78'dir. Ölçeğin ayrılık geçerliğini sınamak için sosyal beğenirlik ölçeği, ölçüt geçerliğini test etmek için ise saldırganlık ölçeği kullanılmıştır. Ahlâkî Uzaklaşma Ölçeği'nin, saldırganlıkla orta düzeyde ilişkili olduğu (r=.33) ancak sosyal beğenirlikle anlamlı ölçüde ilişkili olmadığı (r=.03) bulunmuştur. Ölçeğin psikometrik özelliklerinin yeterli düzeyde olduğu değerlendirilmiştir
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    Anxiolytic, antioxidant, and neuroprotective effects of goji berry polysaccharides in ovariectomized rats: experimental evidence from behavioral, biochemical, and immunohistochemical analyses
    (Tubitak Scientific & Technical Research Council Turkey, 2020) Pehlivan Karakaş, Fatma; Coşkun, Hamit; Soytürk, Hayriye; Bozat, Bihter Gökçe
    Recent studies have indicated that polysaccharides, the main component of the Lycium barbarum L. fruit, have beneficial effects (e.g., anxiolytic, antioxidant, and neuroprotective) on humans and rodents. However, the effects of different dosages of such polysaccharides on ovariectomized rats and their underlying mechanisms in the brain have not been evaluated in the literature. Here, we aimed to evaluate the effects of the high and low doses of polysaccharides obtained from Lycium barbarum fruits (HD-LBP and LD-LBP, respectively) on anxious behaviors via behavioral (using the OFT and EPM), biochemical (using ELISA), and immunohistochemical (using immunohistochemical staining) measures in detail. Two weeks after ovariectomy, the rats were randomly assigned to either the treatment conditions [control (DW, 3 mL/kg, p.o., per day), LD-LBP (20 mg/kg, 3 mL/kg, p.o., per day), HD-LBP (200 mg/kg, 3 mL/kg, p.o., per day), 17 beta-ES (1 mg/kg, 3 mL/kg, p.o., per day), DZ(1 mg/kg, 3 mL/kg, p.o., per day)] or operation type [SHAM (pseudo-ovariectomized) and OVX (ovariectomized)]. The treatments were applied for 30 consecutive days, and then serum and brain tissue samples of all rats were collected. Biochemical (SOD, CAT, GPX, MDA, and 17 beta-ES) and immunohistochemical (BDNF, SER, and apoptosis) analyses of the samples were performed as well. The rats administered HD-LBP and LD-LBP were less anxious than the control groups. The HD-LBP-treated rats had high levels of SOD and low levels of MDA in their serum samples. Moreover, HD-LBP and drug-treated groups had a high number of SER receptors and BDNF-positive cells and a low number of TUNEL-positive cells in their hippocampal brain tissues. The HD-LBP treatments decrease anxious behavior by increasing antioxidant enzyme activities, hippocampal SER and BDNF neurotransmitter levels and decreasing the TUNEL-positive cell count of ovariectomized rats. Given these findings, we suggest that menopause-induced symptoms of anxiety can be reduced by polysaccharides obtained from goji berry fruits, and that these findings will be beneficial for the production studies of natural herbal-origin antianxiety (anxiolytic) drugs in the future.
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    Aromatik Kokuların Bilişsel ve Duygusal EtkileriÜzerine Bir İnceleme
    (2018) Akben, Cantürk; Coşkun, Hamit
    İnsan yaşamında koku duyusu diğer duyulara göre daha az kullanılan bir duyudur. Psikoloji alanında da görsel, işitsel ve dokunmayla ilgili pek çok uyarıcı farklı amaçlarla kullanılırken, kokusal uyaranlar daha az çalışılmaktadır. Bu makalenin amacı psikoloji alanında koku değişkeninin davranışa olan etkisini araştıran çalışmaları incelemektir. Yapılan araştırmalar aromatik kokuların bellekte geri çağırmayı kolaylaştırdığını, duygudurumu olumlu etkilediğini, dikkati artırdığını ve yatıştırıcı etkilerinin olduğuna işaret etmektedir. Beyinde kokunun amigdala ve prefrontal korteksle ilişkili olduğu bulunmuştur. Bu makalede gelecek araştırmalara ışık tutulmaktadır.
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    Beyin fırtınası sürecinde çağrışım alıştırmalarının düşünce üretimine etkisi
    (2009) Coşkun, Hamit
    Literatürde beyin fırtınası gruplarında üyelerden gelen farklı düşüncelerle bilişsel uyarılmaların ortaya çıktığı savunulmakta ve bu durum çağrışımsal bellek yaklaşımıyla açıklanmaktadır (Paulus, 2000). Bununla birlikte, bilişsel uyarılma görüşünün tersine, çağrışımsal bellek yaklaşımı farklı veya uzak olanlara göre birbirine yakın olan düşünceler veya çağrışımlarla beyin fırtınasındaki performansın daha fazla artacağını öngörmektedir (Collins ve Loftus, 1975). Bu farklı iki yaklaşımı test etmeyi amaçlayan 1. deneyde sözcük türü (soyutluk ve somutluk) ile çağrışım türünün (yakın ve uzak), 2. deneyde düşünme türü (ıraksak ve yakınsak) ile çağrışım türünün, 3. deneyde çağrışım türünün düzeyi (yakın, orta ve uzak) ve 4. deneyde gruplarda çağrışım türü ile problem türünün beyin fırtınası performansına etkileri incelenmiştir. Araştırmanın bulguları, çağrışımsal olarak yakın sözcük çiftlerinde alıştırmalar yapan katılımcıların, uzak çiftlerde alıştırma yapanlara göre daha fazla düşünce ürettiklerini göstermektedir. Ayrıca, ıraksak düşünmenin yakın çağrışımlı sözcüklerle düşünce üretim performansını daha fazla artırdığı bulunmuştur. Bu bulgular çoğunlukla çağrışımsal bellek yaklaşımını desteklemektedir.
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    Beyin fırtınasında sosyal kimlik değişiminin üretkenlik üzerine etkisi
    (2005) Coşkun, Hamit
    Bu araştırmada, deneklerin (üniversite öğrencisi) ait oldukları sosyal grup hakkında olumsuz ve olumlu düşünmelerini sağlayan yönergelerle değişimlenen sosyal kimliğin, etkileşim ve nominal (tek başına çalışma) ortamlarda beyin yazımı (düşüncelerin yazılarak paylaşıldığı) modelinde düşünce üretkenliğine etkisi incelenmiştir. Sosyal kimlik iki beyin fırtınası oturumu öncesinde olumludan olumsuza ve olumsuzdan olumluya olmak üzere değiştirilmiştir. Sonuçlar olumsuz-olumlu kimlik değişimi koşulunda bulunanların, olumlu-olumsuz kimlik koşulundakilere kıyasla daha fazla düşünce ürettiklerini göstermektedir. Ayrıca, üniversiteli olmaya yönelik kimliklenme düzeyi yüksek olanlar, düşük olanlara kıyasla daha fazla düşünce üretmektedir. Sonuçlar, sosyal kimlik kuramı ile ilgili beyin fırtınası literatürü ışığında tartışılmıştır.
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    Beyin yaziminda iraksak düşünme ve grup ortaminin düşünce üretimine etkisi
    (2005) Coşkun, Hamit
    The aim of the current study was to assess the influence of convergent and divergent tasks on the idea generation performance. The participants were randomly instructed to generate as many words as they could come up with on the either similarities (convergent task) or differences (divergent task) for the given dual words within the 10 minutes and then brainstormed as dyads in either nominal (nonsharing) and interactive (sharing) condition in a brainwriting paradigm (Paulus & Yang, 2000). All participants as dyads were randomly assigned to either divergent-divergent, divergent-convergent, or convergent-convergent thinking conditions. The dyads in the divergent thinking condition generated more ideas than those in the convergent and mixed thinking conditions. Interactive dyads had also higher number of ideas than nominal ones. These findings were discussed in the lights of the cognitive stimulation and matching perspectives.
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    Beyin yazımında ıraksak düşünme ve grup ortamının düşünce üretimine etkisi
    (2005) Coşkun, Hamit
    Bu araştırmanın amacı, düşünce üretim performansı üzerinde ıraksak ve yakınsak düşünme görevlerinin etkisini değerlendirmektir. Denekler, mümkün olduğunca çok sayıda verilen sözcük çiftlerinin benzerlikleri (yakınsak görev) veya farklılıklarıyla (ıraksak görev) ilgili sözcükleri 10 dakika içinde yaratmaya yönlendirildikten sonra, çiftler halinde nominal (paylaşmama) ve etkileşim (paylaşma) koşullarında beyin yazımı modeline (Paulus ve Yang, 2000) uygun bir beyin fırtınası yöntemiyle düşünceler üretmişlerdir. Tüm denekler çiftler halinde ıraksak-ıraksak, ıraksak-yakınsak (karma) ve yakınsak-yakınsak düşünme koşullarına seçkisiz olarak atanmışlardır. Iraksak düşünme koşuluna atanan çiftler, yakınsak ve karma koşullarda bulunan çiftlere göre daha fazla düşünce üretmişlerdir. Ayrıca, etkileşim çiftlerinin nominal çiftlere göre daha fazla düşüncesi bulunmaktadır. Bu bulgular, bilişsel uyarılma ve eşleştirme açıklamaları ışığı altında tartışılmaktadır.
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    Close associations and memory in brainwriting groups
    (Wiley, 2011) Coşkun, Hamit
    The present experiment examined whether or not the type of associations (close (e. g. apple-pear) and distant (e. g. apple-fish) word associations) and memory instruction (paying attention to the ideas of others) had effects on the idea generation performances in the brainwriting paradigm in which all participants shared their ideas by using paper slips (Paulus & Yang, 2000). All participants were randomly subjected to exercising on either close or distant word associations ten minutes before the brainstorming session started. The findings showed that exercising on the close associations prior to the brainstorming session led to the generation of more unique ideas, category scanning, and depth of ideas than exercising on the distant ones in a subsequent brainstorming task. Memory instruction led to the generation of fewer ideas than no memory instruction. These findings were discussed from the aspect of the associative memory approach and cognitive stimulation approaches.
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    Cognitive stimulation with convergent and divergent thinking exercises in brainwriting - Incubation, sequence priming, and group context
    (Sage Publications Inc, 2005) Coşkun, Hamit
    in two studies, the influence of divergent (generating many words on differences for given dual words) and convergent (generating many words on similarities for given dual words) exercises on the subsequent performance was assessed with dyads in either a nominal or interactive condition in a brainwriting paradigm. In the first study, these cognitive exercises were given after the first session. In the second study, these tasks were presented before each of the two sessions in either the divergent-convergent or convergent-divergent sequences with a temporal order. Exercises on these tasks had no effect on productivity when they preceded the first session of brainstorming. However the provision of a divergent thinking exercise and a convergent-divergent sequence led participants to generate more ideas and scan more categories than their counterparts in the second session. These findings are discussed in light of the cognitive stimulation and incubation perspectives.
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    Comparison of somatization in spinal cord injured patients with healthy individuals purpose
    (2012) Coşkun, Hamit; Göktepe, Salim; Alaca, Ridvan
    The aim of the study was to compare the problem of somatization in patients who had spinal cord injury (SCI) with normal healthy individuals matched for a number of variables. Method: 167 hospitalized patients with spinal cord injury in a rehabilitation clinic and 167 healthy subjects participated in this study. Psychopathological symptoms were measured with the SCL-90 Symptom Inventory. Results: Results of the study showed (1) SCI creates an important problem in patients with somatic expressions, (2) SCI patients who were matched in terms of age, sex, education level and income to normal subjects had higher scores in somatization, depression, anxiety, hostility, phobic anxiety and psychoticism than normal individuals. Discussion and Conclusion: This study objectively showed that use of somatic expressions in SCI patients was not an appropriate approach to evaluate their psychological symptoms. In general, research findings indicated that after controlling for some confounding variables, observed symptom differences between patients and normal individuals provided a supporting evidence for the assumptions of stage theorists.
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    Creativity
    (Taylor and Francis, 2012) Paulus, Paul B.; Coşkun, Hamit
    For many years there was a strong research interest in creativity as an individual activity (Simonton, 1984, 1999; Sternberg, 2006), emphasiz-ing the impact of such personal factors as developmental experiences and thinking styles. Great discoveries in science were mostly attributed to personal genius (Simonton, 1984, 2004). However, in the past 20 years there has been an increasing awareness of the social dynamics involved in creativity (Amabile, 1983; Dacey & Lennon, 1998; Purser & Montuori, 1999), and there has been a strong interest in innovation in work teams and organizations (Choi & Thompson, 2005; Zhou & Shalley, 2007). This interest has led to increased research on the group creative process (Mannix, Neale, & Goncalo, 2009; Paulus & Nijstad, 2003).
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    Do De Bono?s green hat and green-red combination increase creativity in brainstorming on individuals and dyads?
    (Elsevier Sci Ltd, 2022) Göçmen, Öznur; Coşkun, Hamit
    How de Bono's hats affect creativity is an interesting research question. Recent research indicates that the green hat enhances creativity more than the emotional red hat. However, the underlying mechanism of this increase is not yet known since the sample size was small in the previous study. It is also not known what effects the combinations of these hats are on creativity in the groups or dyads. For these purposes, two experiments were conducted. In Experiment 1, in individuals, the green hat increased creativity more than the red one by increasing flexibility. In Experiment 2, the pairs were randomly formed as the green-green, red-red, green-red hat ones. The green-red hat dyads were more creative than the red-red hat ones. These findings indicate the beneficial effect of the combination that dictates creativity and emotionality. These findings were discussed in terms of the cognitive stimulation approach.
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    The effect of intra-amygdalar leptin administration on anxiety, depression and learning behaviors in rats
    (Ondokuz Mayis Universitesi, 2021) Soytürk, Hayriye; Bozat, Bihter Gökçe; Coşkun, Hamit; Karakaş, Fatma Pehlivan
    Leptin is released by adipose tissue. Leptin can cross the blood-brain barrier and bind to receptors on neurons in brain areas to exert its biological function when released into circulation. This study aimed to determine the influences of intra-amygdalar administration of high and low doses of leptin on anxiety, depression, learning behaviors of rats. In the experimental protocol I, intra-amygdalar injection of high and low doses of leptin (0.1 and 1?g/ kg) and saline were administered 30 min before the behavioral tests. Then, the animals were exposed to open field, elevated plus maze, Porsolt and Morris water maze tests for measuring of behaviors. In experimental protocol 2, the cerebrospinal fluids of all groups of experimental protocol 1 were collected by microdialysis method and then were analyzed by HPLC. The effect of the low dose of leptin was significant on the open field. The effect of the high and low dose of leptin was significant on the elevated plus maze test. The effect of the low dose of leptin was significant on mobility in the center of the Porsolt. A high dose of leptin group had spent less time around the platform than controls in the Morris water maze test. HPLC analysis showed that the amount of serotonin and glutamate in the amygdala region increased after low dose leptin administration. Intra-amygdalar injection of low doses of leptin may decrease anxiety and depression-like behavior in rats by increasing serotonin and glutamate levels in the amygdala. © 2021 Ondokuz Mayis Universitesi. All rights reserved.
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    The effects of associative exercises on the idea generation during brainstorming
    (2009) Coşkun, Hamit
    In the literature different ideas coming from members in brainstorming groups have been suggested to generate cognitive stimulation, explained from the perspective of associate memory (Paulus, 2000). However, unlike the cognitive stimulation perspective, the associative memory approach suggests that closely linked ideas or associations can lead to a higher brainstorming performance than different or distant ones (Collins & Loftus, 1975). To test these competing approaches, in Experiment I the effect of concreteness (concrete vs. abstract) and the type of associations (close and distant); in Experiment II that of thinking style (convergent and divergent) and the type of associations; in Experiment III that of the degree of associations (close, moderate, and distant) and thinking style, and in Experiment IV that of problem type and the type of associations in groups were investigated on the brainstorming performance. The findings indicated that closely linked word associations led to the generation of more ideas than their counterparts. Divergent thinking with closely linked word associations was also found to produce the highest brainstorming performance. These findings often supported the associative memory approach.
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    Effects of common daisy (Bellis perennis L.) aqueous extracts on anxiety-like behaviour and spatial memory performance in Wistar albino rats
    (Academic Journals, 2011) Karakaş, Fatma Pehlivan; Karakaş, A.; Coşkun, Hamit; Türker, Arzu Uçar
    The effects of aqueous extract of flowers from Bellis perennis on anxiety-like behavior and memory in Wistar rats were tested. Vehicle 20 and 60 mg kg(-1) B. perennis groups were performed and the animals were tested by open field and elevated plus maze tests for anxiety-like behaviour and Morris water maze test for spatial memory. In the open field, the high dose of B. perennis administrated rats spent more time at the center, showed less mobility and velocity. In the elevated plus maze, the high dose of B. perennis administrated rats spent more time in the open arms, spent less time in the closed arms, were less mobile, were slower and rotated less frequently. In the Morris water maze, the high dose of B. perennis administrated rats spent more of the time to find the platform. In conclusion, B. perennis may produce biphasic effects on both anxiety-like behaviour and learning performance of the rats.
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    The effects of group size, memory instruction, and session length on the creative performance in Electronic Brainstorming Groups
    (2011) Coşkun, Hamit
    In the literature, there has been a focus on the effectiveness of larger sized electronic brainstorming groups; however, mechanisms for its effectiveness still remain open to question and some methodological concerns (e.g., the evaluation of ideas and the typing speed, and the use of different formats) continue to be important problems. To overcome such problems, a series of experiments were conducted. All subjects were exposed to the two-minute typing speed test which was overlooked in the previous studies in electronic brainstorming. In the first experiment the effect of the group size (4, 6, and 8 person groups); in the 2nd experiment that of group size (4, 6, 8, 10, and 12 person groups) with the memory instruction, and in the 3rd experiment that of group size (4 and 10 person groups) with two lengths of brainstorming session (15 and 25 minutes) were investigated on the brainstorming performance. Results showed that unique and original ideas increased as the group size increased. However, the group size did not affect the performance of one individual within these groups. Memory instruction inhibited performance in the shorter session (15 minutes) of brainstorming but enhanced it in the longer session (25 minutes) of brainstorming. Typing speed affected the total number and unique ideas but not the originality and feasibility of these ideas. In conclusion, these findings demonstrated that group size enhanced creative ideas (unique, original, and feasible ideas). Consistent with the literature, the beneficial effect of memory instruction could be evident in the longer session of brainstorming rather than the shorter one. These findings were discussed in light of the relevant brainstorming literature and their implications on educational, health and organizational settings. © 2011 E?itim Dani{dotless}şmanli{dotless}?i{dotless} ve AraŞti{dotless}rmalari{dotless} Iletişim Hizmetleri Tic. Ltd. Şti.
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    The effects of leptin administration to amygdala region on anxiety, depression and learning behaviors: change in seretonine and glutamate levels
    (Wiley-Blackwell, 2016) Orallar, Hayriye; Karakaş, Fatma Pehlivan; Bozat, Bihter Gökçe; Coşkun, Hamit
    AIM: Leptin is a hormone secreted by adipose tissue and involved in modulation of food intake. In addition to these functions, it plays a role in various physiological events such as anxiety, depression and learning. The aim of this study was the investigation of effects of leptin administration to amygdala on anxiety, depression and learning behaviors. In addition, changing of serotonin and glutamate neurotransmitter levels interaction between behavior. METHODS: Presentstudy used Wistar albino rats. Animals were separated 3 groupssuch aslow dose (0.1µg/kg) and high dose (1µg/kg) leptin and saline (control) intraamigdalar administration group. In thisstudy, we planned two procedures. Firstly, a special cannula was implanted into amygdala region of rats and leptin and saline were injected in thisregion by infusion pump. After leptin injections, behavioral tests were performed. In the second study, the extracellular fluid was collected by microdialysis from the amygdale region.The levels of serotonin and glutamate were measured by HPLC. RESULTS: The first experiment demonstrated that in the open field, low dose leptin administrated rats spent more time at the center (F(2,57)= 3.97 p=0.02), showed more zone transition than control ones (F(2,57)= 3.22 p=0.04). In the elevated plus maze, high and low doses leptin administrated rats spent more time in the open arms(F(2,55)= 6.77 p=0.002) and also high dose leptin injected rats showed more frequency of entering open arms (F(2,55)= 9.97 p=0.001). In Porsolt test, low dose leptin administrated ratsshowed high mobility in center than sham group (F(2,55)= 4.30 p=0.02). In the Morris water maze, low dose leptin administrated rats spent more time over the platform (F(2,45)= 3.50 p=0.04). The second experiment demonstrated that serotonin and glutamate levels increased in the first hour after the leptin injections (p<0.05). CONCLUSIONS: Present study suggests that both high and low leptin administration to rat brain playsa role as anxiolytic and antidepression agents in rats
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    The effects of lycium barbarum l. polysaccharides on learning behaviors of young ovariectomized female rats
    (Wiley-Blackwell, 2016) Bozat, Bihter Gökçe; Karakaş, Fatma Pehlivan; Orallar, Hayriye; Coşkun, Hamit
    AIM: Lycium barbarum Linnaeus is also known as goji berry, wolfberry or super fruit. The red-orange and sweet fruits of goji berryhave been used in herbal medicine and health food for the thousand years. L. barbarum fruits have polysaccharides which have many beneficial effects for human such as ocular neuroprotective, antioxidant, immunomodulator, hepatic pretection and antitumor effects. In the present study, the aim was to investigate the effects of the L. barbarum polysaccharides (LBP) on learning behavior in ovariectomized young female rats(two months age) using the Morris water maze test. METHODS: Two weeks after ovariectomy applications, rats were divided into five groups: control (distile water 3 mL/kg, gavage, per day), low dose LBP (20 mg/kg, 3 mL/kg, gavage, per day), high dose LBP (200 mg/kg, 3 mL/kg, gavage, per day), estrogen (1 mg/kg, 3 mL/kg, gavage, per day) and donepezil (1 mg/kg, 3 mL/kg, gavage, per day) and two subgroup within the each group: sham (pseudo ovariectomized rat) and overiectomized groups. After all treatments were applied for thirty consecutive days, behavioral test was applied. Blood serum samples of all rats were collected and levels of antioxidant enzymes (SOD, CAT, GPX, MDA and E2) of the samples were detected by ELISA method. All animals weights were measured weekly. RESULTS: The findings of the present experiment demonstrated that platform finding time and travelled distance of the LBP administred ovariectomized groups were less than estrogen and donepezil administred groups. CONCLUSIONS: In conclusion, LBP enhances the learning performance and antioxidant enzyme activity of ovariectomized female rats.
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    The effects of pinealectomy, melatonin injections and implants on the spatial memory performance of male Wistar rats
    (Taylor & Francis Ltd, 2011) Karakaş, Alper; Coşkun, Hamit; Kaya, Aliye
    Melatonin is the main hormone of the pineal gland that informs the body about the environmental light and darkness regimen and is considered to regulate many important physiological and behavioural activities. In the present study, we examined the effects of pinealectomy, constant-release melatonin implants and timed melatonin injections on spatial memory in male Wistar rats by using Morris water maze. Pinealectomy, melatonin injection and melatonin implantation were performed on groups, including controls for all groups. After a week of the pinealectomy and melatonin implantation surgeries, we applied the injections and made the training trials throughout 4 days. At the fifth day, experiments were performed and recorded. Spatial memory performance of the rats was impaired by the pinealectomy and melatonin injections, since they elongated the latency and shortened the time passed in the correct quadrant. Melatonin implantation did not affect the spatial memory performance of the rats. The latency and the time passed in correct quadrant were not statistically different from their controls. The results suggest that while the removal of the pineal gland and exogenous administration of melatonin via injections are causing impairment, constant-release melatonin administration via implantation does not affect the spatial memory in Wistar albino rats.