Browsing by Subject "PERCEPTION"

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  • Witzel, Christoph; Olkkonen, Maria; Gegenfurtner, Karl R. (2018)
    According to the memory colour effect, the colour of a colour-diagnostic object is not perceived independently of the object itself. Instead, it has been shown through an achromatic adjustment method that colour-diagnostic objects still appear slightly in their typical colour, even when they are colourimetrically grey. Bayesian models provide a promising approach to capture the effect of prior knowledge on colour perception and to link these effects to more general effects of cue integration. Here, we model memory colour effects using prior knowledge about typical colours as priors for the grey adjustments in a Bayesian model. This simple model does not involve any fitting of free parameters. The Bayesian model roughly captured the magnitude of the measured memory colour effect for photographs of objects. To some extent, the model predicted observed differences in memory colour effects across objects. The model could not account for the differences in memory colour effects across different levels of realism in the object images. The Bayesian model provides a particularly simple account of memory colour effects, capturing some of the multiple sources of variation of these effects.
  • Ryynänen, Toni; Heinonen, Visa (2021)
    Purpose Temporal consumption experiences have been conceptualised as universal, subjective or practice-based experiences. Little research, though, addresses such experiences in conjunction with the repeated and situational consumption events that bring them about. The purpose of this paper is to extend current knowledge by examining how the temporal and situational intertwine during consumption events. For this purpose, the concept of a consumption timecycle based on the research data is constructed. Design/methodology/approach The paper takes a longitudinal and researcher-led approach to study temporal consumption experiences. The data was collected through participant observations, video recordings and personal subjective introspections during three consecutive annual Nordic motorcycle consumer trade shows (2014-2016). The data was analysed using an interpretive approach. Findings The results demonstrate five temporalities that characterise a consumption timecycle as follows: emerging, core, intensifying, fading and idle-time temporalities. The features of these temporal experiences are presented in the conclusions section of the paper. Research limitations/implications Recalled temporal experiences are mediated experiences and they differ from lived experiences. The transferability or generalisability of the results might be limited, as the case is situated in the Nordic context. Originality/value The paper presents the novel concept of a consumption timecycle that extends current debates about consumer time. The consumption timecycle is contrasted with established temporal concepts in consumer and marketing research.
  • Hosoya, Haruo; Hyvärinen, Aapo (2017)
    Experimental studies have revealed evidence of both parts-based and holistic representations of objects and faces in the primate visual system. However, it is still a mystery how such seemingly contradictory types of processing can coexist within a single system. Here, we propose a novel theory called mixture of sparse coding models, inspired by the formation of category-specific subregions in the inferotemporal (IT) cortex. We developed a hierarchical network that constructed a mixture of two sparse coding submodels on top of a simple Gabor analysis. The submodels were each trained with face or non-face object images, which resulted in separate representations of facial parts and object parts. Importantly, evoked neural activities were modeled by Bayesian inference, which had a top-down explaining-away effect that enabled recognition of an individual part to depend strongly on the category of the whole input. We show that this explaining-away effect was indeed crucial for the units in the face submodel to exhibit significant selectivity to face images over object images in a similar way to actual face-selective neurons in the macaque IT cortex. Furthermore, the model explained, qualitatively and quantitatively, several tuning properties to facial features found in the middle patch of face processing in IT as documented by Freiwald, Tsao, and Livingstone (2009). These included, in particular, tuning to only a small number of facial features that were often related to geometrically large parts like face outline and hair, preference and anti-preference of extreme facial features (e.g., very large/small inter-eye distance), and reduction of the gain of feature tuning for partial face stimuli compared to whole face stimuli. Thus, we hypothesize that the coding principle of facial features in the middle patch of face processing in the macaque IT cortex may be closely related to mixture of sparse coding models.
  • Zhdanov, Andrey; Nurminen, Jussi; Baess, Pamela; Hirvenkari, Lotta; Jousmaki, Veikko; Makela, Jyrki P.; Mandel, Anne; Meronen, Lassi; Hari, Riitta; Parkkonen, Lauri (2015)
    Hyperscanning Most neuroimaging studies of human social cognition have focused on brain activity of single subjects. More recently, "two-person neuroimaging" has been introduced, with simultaneous recordings of brain signals from two subjects involved in social interaction. These simultaneous "hyperscanning" recordings have already been carried out with a spectrum of neuroimaging modalities, such as functional magnetic resonance imaging (fMRI), electroencephalography (EEG), and functional near-infrared spectroscopy (fNIRS). Dual MEG Setup We have recently developed a setup for simultaneous magnetoencephalographic (MEG) recordings of two subjects that communicate in real time over an audio link between two geographically separated MEG laboratories. Here we present an extended version of the setup, where we have added a video connection and replaced the telephone-landline-based link with an Internet connection. Our setup enabled transmission of video and audio streams between the sites with a one-way communication latency of about 130 ms. Our software that allows reproducing the setup is publicly available. Validation We demonstrate that the audiovisual Internet-based link can mediate real-time interaction between two subjects who try to mirror each others' hand movements that they can see via the video link. All the nine pairs were able to synchronize their behavior. In addition to the video, we captured the subjects' movements with accelerometers attached to their index fingers; we determined from these signals that the average synchronization accuracy was 215 ms. In one subject pair we demonstrate inter-subject coherence patterns of the MEG signals that peak over the sensorimotor areas contralateral to the hand used in the task.
  • Grimaldi, Mirko; Sisinni, Bianca; Fivela, Barbara Gili; Invitto, Sara; Resta, Donatella; Alku, Paava; Brattico, Elvira (2014)
  • Szibor, Annett; Lehtimäki, Jarmo; Ylikoski, Jukka; Aarnisalo, Antti A.; Mäkitie, Antti; Hyvärinen, Petteri (2018)
    Affective processing appears to be altered in tinnitus, and the condition is to a large extent characterized by the emotional reaction to the phantom sound. Psychophysiological models of tinnitus and supporting brain imaging studies have suggested a role for the limbic system in the emergence and maintenance of tinnitus. It is not clear whether the tinnitus-related changes in these systems are specific for tinnitus only, or whether they affect emotional processing more generally. In this study, we aimed to quantify possible deviations in affective processing in tinnitus patients by behavioral and physiological measures. Tinnitus patients rated the valence and arousal of sounds from the International Affective Digitized Sounds database. Sounds were chosen based on the normative valence ratings, that is, negative, neutral, or positive. The individual autonomic response was measured simultaneously with pupillometry. We found that the subjective ratings of the sounds by tinnitus patients differed significantly from the normative ratings. The difference was most pronounced for positive sounds, where sounds were rated lower on both valence and arousal scales. Negative and neutral sounds were rated differently only for arousal. Pupil measurements paralleled the behavioral results, showing a dampened response to positive sounds. Taken together, our findings suggest that affective processing is altered in tinnitus patients. The results are in line with earlier studies in depressed patients, which have provided evidence in favor of the so-called positive attenuation hypothesis of depression. Thus, the current results highlight the close link between tinnitus and depression.
  • Petersen, Bjorn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sorensen, Stine Derdau; Vuust, Peter (2015)
    Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users.
  • Rummukainen, Olli; Radun, Jenni; Virtanen, Toni; Pulkki, Ville (2014)
  • Virtanen, Lari S.; Olkkonen, Maria; Saarela, Toni P. (2020)
    Color serves both to segment a scene into objects and background and to identify objects. Although objects and surfaces usually contain multiple colors, humans can readily extract a representative color description, for instance, that tomatoes are red and bananas yellow. The study of color discrimination and identification has a long history, yet we know little about the formation of summary representations of multicolored stimuli. Here, we characterize the human ability to integrate hue information over space for simple color stimuli varying in the amount of information, stimulus size, and spatial configuration of stimulus elements. We show that humans are efficient at integrating hue information over space beyond what has been shown before for color stimuli. Integration depends only on the amount of information in the display and not on spatial factors such as element size or spatial configuration in the range measured. Finally, we find that observers spontaneously prefer a simple averaging strategy even with skewed color distributions. These results shed light on how human observers form summary representations of color and make a link between the perception of polychromatic surfaces and the broader literature of ensemble perception.
  • Puhakka, Riikka; Ollila, Sari; Valve, Raisa; Sinkkonen, Aki Tapio (2019)
    A health effect is a credence quality feature which is difficult for consumers to detect, and they need to be convinced of its trustworthiness. This study explores the role of trust-related arguments in Finnish, German, and British consumers' willingness to try a novel health-enhancing, non-edible product. Scientific evidence in particular would convince consumers, particularly Finnish ones, to try a product. Receiving recommendations from other users was more important for younger than for older respondents when it came to trying this type of product. Different marketing strategies may be needed to convince potential users of the benefits of a novel product.
  • Jasinskaja-Lahti, Inga; Renvik (Mähönen), Tuuli Anna; van der Noll, Jolanda; Eskelinen, Viivi; Rohmann, Anette; Verkuyten, Maykel (2020)
    This survey experiment examined national majority group members' reactions to immigrants' citizenship status with a focus on dual citizenship. A sample of 779 participants (n(Finland) = 174; n(Netherlands) = 377; n(Germany) = 228) was used to examine whether immigrants' citizenship status affects trust towards immigrants, willingness to accept immigrants in strategic positions, and support for immigrants' social influence in society. Perceived group loyalties were expected to mediate these relationships. Compared to national citizens, dual citizens were perceived as having lower national loyalty and higher foreign loyalty. Compared to foreign citizens, dual citizens were perceived to have higher national loyalty but equally high foreign loyalty. Higher national loyalty was further associated with higher trust, acceptance, and support, whereas higher foreign loyalty was associated with lower trust, acceptance, and support. These findings are discussed in relation to societal debates on dual citizenship and the limited social psychological research on this topic.
  • Poikonen, Hanna Liisa; Toiviainen, Petri; Tervaniemi, Mari Anni Irmeli (2016)
    The neural responses to simple tones and short sound sequences have been studied extensively. However, in reality the sounds surrounding us are spectrally and temporally complex, dynamic and overlapping. Thus, research using natural sounds is crucial in understanding the operation of the brain in its natural environment. Music is an excellent example of natural stimulation which, in addition to sensory responses, elicits vast cognitive and emotional processes in the brain. Here we show that the preattentive P50 response evoked by rapid increases in timbral brightness during continuous music is enhanced in dancers when compared to musicians and laymen. In dance, fast changes in brightness are often emphasized with a significant change in movement. In addition, the auditory N100 and P200 responses are suppressed and sped up in dancers, musicians and laymen when music is accompanied with a dance choreography. These results were obtained with a novel event-related potential (ERP) method for natural music. They suggest that we can begin studying the brain with long pieces of natural music using the ERP method of electroencephalography (EEG) as has already been done with functional magnetic resonance (fMRI), these two brain imaging methods complementing each other.
  • Nowak, Kamila; Oron, Anna; Szymaszek, Aneta; Leminen, Miika; Naatanen, Risto; Szelag, Elzbieta (2016)
    The present study investigates age-related changes in duration discrimination in millisecond time domain. We tested young (N = 20, mean age = 24.5, SD = 2.97) and elderly (N = 20, mean age = 65.2, SD = 2.94) subjects using the mismatch negativity (MMN) paradigm. White-noise bursts of two different durations (50 and 10 ms) were presented in two oddball blocks. In one block (Increment Condition), the repetitive sequence of 10 ms standards was interspersed by occasional 50 ms deviants. In the Decrement Condition, the roles of the two stimuli were reversed. We analyzed the P1-N1 complex, MMN and P3a and found the effect of age for all these components. Moreover, the impact of stimulus presentation condition (increment/decrement) was observed for MMN and P3a. Our results confirmed the previous evidence for deteriorated duration discrimination in elderly people. Additionally, we found that this effect may be influenced by procedural factors.
  • Zhu, Yongjie; Zhang, Chi; Poikonen, Hanna; Toiviainen, Petri; Huotilainen, Minna; Mathiak, Klaus; Ristaniemi, Tapani; Cong, Fengyu (2020)
    Recently, exploring brain activity based on functional networks during naturalistic stimuli especially music and video represents an attractive challenge because of the low signal-to-noise ratio in collected brain data. Although most efforts focusing on exploring the listening brain have been made through functional magnetic resonance imaging (fMRI), sensor-level electro- or magnetoencephalography (EEG/MEG) technique, little is known about how neural rhythms are involved in the brain network activity under naturalistic stimuli. This study exploited cortical oscillations through analysis of ongoing EEG and musical feature during freely listening to music. We used a data-driven method that combined music information retrieval with spatial Fourier Independent Components Analysis (spatial Fourier-ICA) to probe the interplay between the spatial profiles and the spectral patterns of the brain network emerging from music listening. Correlation analysis was performed between time courses of brain networks extracted from EEG data and musical feature time series extracted from music stimuli to derive the musical feature related oscillatory patterns in the listening brain. We found brain networks of musical feature processing were frequency-dependent. Musical feature time series, especially fluctuation centroid and key feature, were associated with an increased beta activation in the bilateral superior temporal gyrus. An increased alpha oscillation in the bilateral occipital cortex emerged during music listening, which was consistent with alpha functional suppression hypothesis in task-irrelevant regions. We also observed an increased delta-beta oscillatory activity in the prefrontal cortex associated with musical feature processing. In addition to these findings, the proposed method seems valuable for characterizing the large-scale frequency-dependent brain activity engaged in musical feature processing.
  • Saarikallio, Suvi; Tervaniemi, Mari; Yrtti, Antti; Huotilainen, Minna (2019)
    While the use of musical parameters for emotional expression has been extensively studied, little is known about which specific musical parameters children at different ages are able to use for expressing specific emotions. We used a novel interface called Music Box that allows modification of musical parameters while music is being played in real time. Children (N = 37, 18 girls) at the age of 3 and 5 were asked to modify three parameters – tempo, loudness, and pitch – in expressing three emotions – happiness, sadness, and anger. We hypothesised that both 5-year-olds and 3-year-olds could use each of the parameters in differentiating between the emotions. Results showed that 3-year-olds were equally competent than 5-year-olds in using the parameters. Differences based on gender and music background were additionally measured. The study provides knowledge on normative development of children’s ability for musical expression of emotion, which can be used to inform music education and music therapy practices.
  • Vainio, Martti; Järvikivi, Juhani (2007)
  • Hoppu, Ulla; Puputti, Sari; Mattila, Saila; Puurtinen, Marjaana; Sandell, Mari (2020)
    The food experience is multisensory and multisensory external stimuli may affect food choice and emotions. The objective of this study was to evaluate the effect of a multisensory eating environment on food choice, intake and the emotional states of the subjects in a salad lunch buffet setting. A total of 30 female subjects consumed a salad lunch twice in the multisensory laboratory. The two test conditions (control and multisensory condition with environmental stimuli) were randomized and the visits were scheduled one week apart. Subjects selected and ate a meal from a salad buffet including 14 food items and the intake of each item was weighed. They answered an online questionnaire about the meal and their emotional states (20 different emotion terms) after the lunch. There was no significant difference in the food consumption between the control and multisensory conditions. The subjects were very satisfied with their lunch for both study visits but the pleasantness of the eating environment was rated higher under the multisensory condition. In emotional terms, the subjects selected the term "happy" significantly more frequently under the multisensory condition compared with the control. In conclusion, the multisensory eating environment in this study was not related to food intake but may be associated with positive emotions. The effect of the eating environment on food choice and experience deserves further study with a larger study population in a real lunch restaurant setting.
  • Cowley, Benjamin; Lukander, Kristian (2016)
    Background: Recognition of objects and their context relies heavily on the integrated functioning of global and local visual processing. In a realistic setting such as work, this processing becomes a sustained activity, implying a consequent interaction with executive functions. Motivation: There have been many studies of either global-local attention or executive functions; however it is relatively novel to combine these processes to study a more ecological form of attention. We aim to explore the phenomenon of global-local processing during a task requiring sustained attention and working memory. Methods: We develop and test a novel protocol for global-local dissociation, with task structure including phases of divided ("rule search") and selective ("rule found") attention, based on the Wisconsin Card Sorting Task (WCST). We test it in a laboratory study with 25 participants, and report on behavior measures (physiological data was also gathered, but not reported here). We develop novel stimuli with more naturalistic levels of information and noise, based primarily on face photographs, with consequently more ecological validity. Results: We report behavioral results indicating that sustained difficulty when participants test their hypotheses impacts matching-task performance, and diminishes the global precedence effect. Results also show a dissociation between subjectively experienced difficulty and objective dimension of performance, and establish the internal validity of the protocol. Contribution: We contribute an advance in the state of the art for testing global local attention processes in concert with complex cognition. With three results we establish a connection between global local dissociation and aspects of complex cognition. Our protocol also improves ecological validity and opens options for testing additional interactions in future work.
  • Kostilainen, Kaisamari; Wikstrom, Valtteri; Pakarinen, Satu; Videman, Mari; Karlsson, Linnea; Keskinen, Maria; Scheinin, Noora M.; Karlsson, Hasse; Huotilainen, Minna (2018)
    We evaluated the feasibility of a multi-feature mismatch negativity (MMN) paradigm in studying auditory processing of healthy newborns. The aim was to examine the automatic change-detection and processing of semantic and emotional information in speech in newborns. Brain responses of 202 healthy newborns were recorded with a multi-feature paradigm including a Finnish bi-syllabic pseudo-word/ta-ta/as a standard stimulus, six linguistically relevant deviant stimuli and three emotionally relevant stimuli (happy, sad, angry). Clear responses to emotional sounds were found already at the early latency window 100-200 ms, whereas responses to linguistically relevant minor changes and emotional stimuli at the later latency window 300-500 ms did not reach significance. Moreover, significant interaction between gender and emotional stimuli was found in the early latency window. Further studies on using multi-feature paradigms with linguistic and emotional stimuli in newborns are needed, especially those containing of follow-ups, enabling the assessment of the predictive value of early variations between subjects.
  • Pavicic, M.; Wang, F.; Mouhu, K.; Himanen, K. (2019)
    Seed quality is an important factor for seedling vigour as well as adult plant resilience. The key quality attributes are related to physical characteristics, physiological performance, genetic background and health status of the seeds. Many ways to address seed quality attributes have been developed and recently many of them have featured automated high throughput methods. In our study, we addressed two of the seed quality attributes, namely physiological performance and genetic background by analysing germination rates in our mutant collection. These mutants represent ubiquitin E3 ligases that transcriptionally respond to abscisic acid (ABA). This plant hormone is an important regulator of germination and seedling establishment. To facilitate in vitro germination screens of large seed collections a high throughput image-based assay was developed. As a read out of the germination on ABA treatment the cotyledon emergence was detected with top view chlorophyll fluorescence camera. By applying the ABA treatment during germination, RING-type ubiquitin E3 ligase mutants were identified, showing either resistant or sensitive responses to ABA. In conclusion, a scalable high throughput screen for in vitro germination assay was established that allowed fast screening of tens of mutants in a hormone supplemented media.