This study was supported by grants from the Ministry of Science and Technology, Taiwan, R.O.C. [NSC-101-2410-H-439-001] to the first author, Tuyuan Cheng. The authors thank lab members, Yang Ya-Hui and Chen&#160;Pei-Han, in NTIN, for their assistance in preparing and conducting the experiment.

The administration of these experiments followed all research ethics regulations. All subjects provided informed verbal and written consent before the experiments were administered. All the procedures, consent forms, and the experimental protocol were approved by the Research Ethics Committee of the National Cheng Kung University in Taiwan. Experiment 1 and Experiment 2 were respectively based on prior studies18,19. Representative results reported here are adopted from these previous publications.
1. Experiment 1&#8213;dual-modal intrasentential interference task
<ol>
	<li>Recruit 97 students, 54 females and 42 males, from the National Tainan Institute of Nursing and the National Tainan Secondary High School to participate in Experiment 1. 
	NOTE: All participants are required to be fluent native Chinese speakers with normal or corrected-to-normal vision and no auditory impairment by self-report.</li>
	<li>Material preparation
	<ol>
		<li>Select words and nonwords for the LDT. Include a total of 48 bisyllabic (two-character) Chinese words, of which 24 were words and 24 were nonwords. 
		NOTE: A Chinese character represents a syllable, which is usually a morpheme (i.e., the smallest meaningful element). The target words here are bisyllabic compound words. Please see the Supplemental File for a list of the visual target words/nonwords used for the LDT task.
		<ol>
			<li>Select the 24 words from the Sinica Corpus Technical Report20, while ensure that all of the target words are of medium frequency. Search words of the mean frequency percentage approximately 0.00030 and the ranking order approximately 4,000 in the database. 
			NOTE: Choosing words of medium frequency as the target words is intended to reduce the frequency effect, which results in shorter response times (RTs) for high-frequency words and longer RTs from low-frequency words.</li>
			<li>Create the 24 nonwords by using two monosyllabic characters that are individually meaningful but whose combination is semantically anomalous. To prevent potential activations, avoid bisyllabic-character words with identical radicals (e.g., haiyang, meaning &#8216;ocean&#8217;, is represented in a Chinese bisyllabic character word as <img alt="Charcter 1" src="/files/ftp_upload/59660/59660char01.jpg" />, where the radical component &#160;<img alt="Charcter 3" src="/files/ftp_upload/59660/59660char03.jpg" style="opacity: 0.9;" />&#160;related to waters is shared in the characters&#160;<img alt="Charcter 2" src="/files/ftp_upload/59660/59660char02.jpg" style="opacity: 0.9;" />&#160;and <img alt="Charcter 4" src="/files/ftp_upload/59660/59660char04.jpg" />).</li>
			<li>Collocate manually the 24 nonwords in filler sentences and the 24 words in target RC sentences. 
			NOTE: Collocating words with RCs and nonwords with fillers was necessary because only the RTs of LDT from the 24 words with RCs should be considered and included in the statistical analyses.</li>
		</ol>
		</li>
		<li>Auditory RC and filler sentences 
		NOTE: Please see the Supplemental File for examples of the SRC, ORC, and filler sentences.
		<ol>
			<li>Compose the auditory stimuli into 72 sentences, involving three types of sentences: 24 SRCs, 24 ORCs, and 24 filler sentences.</li>
			<li>Divide the 48 RC sentences evenly into two groups to create an incomplete-counterbalanced design, forming 48 trials (12 SRCs, 12 ORCs, and 24 fillers) in the 2 (SRC, ORC) * 3 (probing site) * 2 (word/nonword) conditions.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Setting up the experimental software
	<ol>
		<li>Use a standard experimental software (i.e., E-Prime21) to program the experiment according to the software protocols.</li>
		<li>Randomize all the stimuli using the experimental software.</li>
		<li>Configure the software system to record the following data: (1) the response time, (2) the accuracy rate of the participant&#8217;s responses in the LDT, and (3) the postsentence comprehension based on the participants&#8217; keyboard presses.</li>
		<li>Include feedback regarding participants&#8217; incorrect lexical decision or no response. Display feedback on the monitor screen immediately after the participant&#39;s incorrect or missing response. No feedback is shown when the participant&#8217;s response was correct.</li>
		<li>Provide a practice section involving trials with feedback.</li>
	</ol>
	</li>
	<li>After the practice session, start the dual-modal intrasentential LDT interference task. During the experimental sessions, allow the participants to take a break between every 24 trials.
	<ol>
		<li>Have each participant perform the task individually. First, provide the participants with instructions both in written form on the computer screen and in verbal form by the experimenter. Seat the participants in front of a computer and equip them with headphones.</li>
		<li>Instruct the participants to listen to the sentences played through their headphones, while simultaneously, at some point during the listening process, to perform a lexical decision task.</li>
		<li>Ask the participants to decide whether the interfering visual probe displayed on the screen was a word or nonword and instruct them to press the response key &#8216;Yes&#8217; for a word or &#8216;No&#8217; for a nonword as quickly and accurately as possible.</li>
		<li>Inform the participants that a comprehension question would follow immediately after the sentence. Remind them to listen attentively to the auditory sentence while simultaneously perform the LDT task.</li>
	</ol>
	</li>
</ol>
2. Experiment 2&#8213;dual-modal extrasentential interference task
<ol>
	<li>Recruit 61 college students, 40 females and 21 males, from the National Taipei University of Technology and the National Tainan Junior College of Nursing as participants in Experiment 2. 
	NOTE: All the participants are required to be fluent native Chinese speakers with normal or corrected-to-normal visual acuity and no auditory impairment by self-report.</li>
	<li>Material preparation
	<ol>
		<li>Auditory RC and filler sentences
		<ol>
			<li>Compose the auditory stimuli into three types of sentences: SRCs, ORCs, and filler sentences. Divide the 48 RC sentences evenly into two groups to create an incomplete counterbalanced design with 96 total trials (24 SRCs, 24 ORCs, and 48 fillers) for the 2 (sentence type: SRC, ORC) * 3 (digit load) conditions. 
			NOTE: Please see the Supplemental File for target auditory trial examples of the SRC, ORC, and filler sentences.</li>
		</ol>
		</li>
		<li>0/3/5 digits
		<ol>
			<li>Construct a total of 96 digital items, comprised of 0/3/5 digit combinations. Assign each 0, 3, or 5 digit load evenly to all the sentence trials.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Dual modal extrasentential digital interference task with AMW paradigm
	<ol>
		<li>Use a standard experimental software (i.e., E-Prime21) to program the experiment according to the software protocols.</li>
		<li>Randomly assign the participants to one of the two stimuli sets representing combinations of two within-subject factors of sentence type (SRC vs. ORC) and memory load (no load, 3-digit- load, 5-digit-load).Provide the participants with the 1,500 ms visual presentation of the digits before the AMW task.</li>
	</ol>
	</li>
	<li>Then, start the AMW task. 
	NOTE: The AMW task22 is a self-paced listening task.
	<ol>
		<li>Instruct the participants to keep the preceding visual presentation (digits or no digits) in memory.</li>
		<li>Then, instruct the participants to listen to the sentences segmented into words and played through their headphones. Tell them to pace themselves as quickly as possible by pressing the keyboard to initiate playing of the subsequent segmented word.</li>
		<li>Instruct the participants to answer the yes/no comprehension question that appeared on the computer screen after they have listened to each trial sentence. Inform the participants that the question is preceded by a question mark &#8220;?&#8221; on the computer screen and that the question is related to the information they have heard in the preceding sentence.</li>
		<li>A short &#8220;beep&#8221; sound is played when the participants press the yes/no key to answer the comprehension question. After the beep, following the instruction appearing on the screen, ask the participants to repeat the digit they have seen prior to listening to the sentence.</li>
		<li>Have the experimenter to record the participants&#8217; digit-recall responses on a score sheet.</li>
	</ol>
	</li>
</ol>

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The authors have nothing to disclose.

This study demonstrates that using DMI methods with both intra- and extrasentential interference tasks can help to elucidate the role of WM in spoken sentence processing and shed light on the issue of Chinese RC processing asymmetry. As expected, by measuring the extent to which interference from a secondary task affected listeners&#8217; performances on primary sentence processing, we can infer the patterns of Chinese RC processing and arrive at a feasible solution to the debate on the Chinese SRC/ORC processing advanta...

The role of working memory (WM) during spoken sentence processing is self-evident: due to the transient nature of speech, listeners must retain the component acoustic forms in their memories until they are processed. This aspect becomes even more important during&#160;processing of syntactically complex sentences. Assigning syntactic relations to words in complex sentences involves performing computational operations on items retained in memory for short periods of time, resulting in a higher memory demand. However, how the WM system is involved in spoken sentence processing is controversial.
This controversy involves two major disagreements: some researchers argue that a single WM system exists that is used for all verbal tasks1,2&#8212;in other words, syntactic processing relies on the same memory resources used by more general cognitive processes. This is the single-resource model. Others have claimed that determining the meaning of a sentence based on its syntactic structure involves a specialized WM system separate from that used for other verbal tasks3,4. In this vein, syntactic processing is modular. This is the separate-sentence-interpretation resource model.
In psycholinguistic research, the dual-modal interference paradigm has been used to examine the two competing accounts. Based on the assumption that WM storage capacity is limited5,6, the paradigm addresses issues by complicating a primary task with a secondary intervening task. Given that the primary task competes for limited resources with the secondary intervening task, the difficulty increases and the primary task exhibits longer reaction times. Given this situation, the dual-modal interference approach makes it possible to assess the processing load and extent of the WM&#8217;s involvement when a participant is given a task that requires fulfilling both tasks simultaneously.
Sentences containing RC components, which cause more comprehension difficulties due to their well-known complex syntactic structures, are widely used to investigate how the WM system is involved in processing complex sentences. However, although processing complex sentences places a higher demand on the WM resources associated with speech processing, it is less clear whether the WM that is thought to contribute to the costs of syntactic movements in languages with head-initial RC constructions (such as English) reflects the syntactic complexity of languages with head-final RCs (such as Chinese). Through the use of a dual-modal interference paradigm, the current study sheds light on this issue.
The difficulties associated with processing two RC structures, subject-gapped and object-gapped relative clauses (SRCs vs. ORCs), have been the subject of extensive debate. These controversies are mainly observed across typologically different languages. In head-initial languages such as English, in which a relative clause follows the head noun it modifies, the general finding is that SRCs such as in example 1(a) below are processed more easily than ORCs in example 1(b).
<img alt="Equation 1" src="/files/ftp_upload/59660/59660equ01.jpg" />
As shown in example (1), in English, the surface location of the gap differs minimally between SRCs and ORCs. This gap is indexed as e1, the empty position after the head noun &#8216;actor&#8217; (called filler) left by its removal out of the RC. However, SRCs and ORCs differ substantially in terms of the grammatical structure and function of the gap in the RC domain. The memory cost for integrating and resolving the structural dependency between the filler and the gap is an apt target for experimental study and has been widely used to gain insights into the role of WM in language processing and comprehension.
For example, comprehending and processing these postnominal RCs requires indexing the head noun &#8216;actor&#8217; as either a functional subject or the object of the verb &#8216;criticized&#8217; in SRC and ORC and then storing the head noun in WM so it can later be assigned to the grammatical subject of the verb &#8216;admitted&#8217; in the main clause.
In contrast to the consistent finding with head-initial languages that comprehending SRCs is easier than comprehending ORCs, mixed results have been reported regarding the RC processing asymmetry for Chinese, which is a head-final language in which a relative clause precedes the head noun. Some have observed an SRC processing advantage, while others have reported the opposite pattern (i.e., an ORC processing advantage). The latter lines of research also proposed that RC processing asymmetry can be modulated by WM, as suggested by results obtained from studies of self-paced reading performance7,8,9.
As mentioned above, there are two competing models regarding the role that WM plays in the (complex) syntactic processing. One is that &#8220;syntactic processing is modular&#8221;, and the other is that &#8220;syntactic processing is general&#8221;. Complex sentences with well-known differences in comprehension difficulty, i.e., SRCs vs. ORCs in English, are frequently used in dual-modal interference (DMI) tasks to examine these two assertions with respect to the question of modularity because the involvement of WM is claimed to parallel the processing asymmetry. Thus, inducing concurrent memory load through interfering tasks demonstrates WM effects on syntactic processing. The rationale is that whether a single verbal WM system or separate modular syntactic systems exist, engaging the system with an interfering task makes syntactic processing less efficient due to WM resource limitations. The way in which processing syntactically more complex sentences (ORC, in English) suffers in DMI tasks compares to processing syntactically simpler sentences (SRC, in English) provides evidence regarding the specific effect of WM and indicates the extent to which WM is involved.
In contrast to head-initial languages such as English, Chinese RCs manifests a head-final formation and exhibits a gap-filler relationship. The indexed moved-out element, the gap, precedes the head noun associating&#160;with it, as illustrated in 2(a), SRC, and 2(b), ORC.
<img alt="Equation 1" src="/files/ftp_upload/59660/59660equ02v2.jpg" />
The controversy that stems from processing Chinese RCs is that SRCs are not consistently reported as easier to process than ORCs, and this discrepancy has posed a challenge for theories of language processing and comprehension. Because the prenominal content before the relativizer &#8216;DE&#8217; must be stored in WM until after the gap&#8212;the moved head noun &#8216;actor&#8217;, is linked and retrieved&#8212;understanding this process still helps in obtaining insights into the role of WM in language processing.
In the current study, spoken RC sentence processing is examined because listening is highly compressive during processing and is closely related to the functioning of WM. The dual modal interference paradigm is used because interference is a well-established forgetting function in short-term auditory memory. Representations stored in memory can be degraded and subsequently lost when interfering events occur10. Distractors that vary along different aspects (in the current case: intralinguistic and extradigital, see below) to the canonical spoken sentence allow us to measure the cost of integrating the incremental input during different processing phases and under differing interference conditions.
Based on the position that processing more syntactically complex sentences overloads WM more than does processing simpler sentences, one can hypothesize that manipulating the type of interference during the course of comprehension should have effects on sentence processing. By implication, processing syntactically more complex sentences will require either proportionately greater or disproportionately greater listening times online and show worse performance in postonline sentence comprehension assessment than will processing syntactically simpler constructions. The current study examines the hypothesis that interference during sentence processing can index WM involvement and virtually places its value beyond the issue of syntactic modularity: it proposes the idea that the controversy over Chinese RC processing can be elucidated through the investigation of WM due to its fundamental role in language comprehension. Therefore, the significance attached to the use of DMI tasks in Chinese RC processing provides a path to solving the ongoing debate concerning Chinese RC processing asymmetry.
This article presents two exemplar experiments involving auditory processing using both intra- and extrasentential interference. The goal of these two experiments was to explore to what extent WM is engaged in processing Chinese RC under differing types of interference.
In the first experiment, a visually presented lexical decision task was used as the intrasentential interference. As a secondary interfering task, the word/nonword lexical decision task (LDT) was introduced at three points during the auditory presentation of the target relative clause sentence, thus allowing the processing difficulty to be measured at these points. The major concern in this experiment is how the gap in the relative clause (RC) is associated with the filler in the matrix clause (MC) and whether it affects the processing of subsequent MC. Therefore, the three probing sites to be measured were set after the MC region. An example, replicated from (2), of the three probing sites indicated with arrows and aligned with corresponding syntactic concatenation, is illustrated in example 3, where 3(a) shows SRC and 3(b) shows ORC.
<img alt="Equation 1" src="/files/ftp_upload/59660/59660equ03v2.jpg" />
Figure 1 shows the procedure of interfering with the continuous auditory RC presentation by the LDT at any of the three probing sites. The timing design follows the conventional protocol of the LDT task in a previous Chinese processing study11. For example, each visual LDT trial begins with a cross sign &#8220;+&#8221; that indicates a fixation point in the center of the monitor for 500 ms, followed by the visual LDT stimulus, which is displayed on the screen for 3,000 ms and disappears immediately after the subject makes the lexical decision. A typical subject completes Experiment 1, including the practice session, within 30&#8211;35 minutes.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/59660/59660fig01.jpg" /> 
Figure 1: Intrasentential interference procedure with a lexical decision task. 
<a href="https://www.jove.com/files/ftp_upload/59660/59660fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
The three probing sites along with the LDT task:
1. Position 1 (P1): Post-SMC region
The first position (P1) to be measured is immediately after the subject of the MC at the region after the RC boundary. Processing load is expected to incur at this site. For one thing, prior to this point (SMC), subject-gap and object-gap construction within the RC domain form contrastive verb-object (VO) and subject-verb (SV) structures, respectively. For another, to integrate the constituents in the RC region with the head noun in MC, listeners must identify the grammatical role of the gap and link it with the upcoming filler head noun
2. Position 2 (P2): Post-VMC region
The second position (P2) to be measured is immediately after the verb in the matrix clause (VMC). This site is also assumed to induce processing load. Integrating the verbal information requires listeners to retrieve the noun arguments in the sentence and to identify the agent of the matrix verb either from the preceding RC domain or from the head noun that the RC modifies.
3. Position 3 (P3): Postsentence region
The third position (P3) to be measured is immediately after the end of the sentence. Previous studies on processing propose that there is an end-of-sentence wrap-up effect&#8212;a phenomenon in which nonsyntactic information (e.g., discourse and semantic level) are considered at the end of a sentence to activate and complete comprehension12,13. Therefore, processing load should increase toward the end of the sentence due to the need to integrate this nonsyntactic information14,15. Position 3 is assumed to show a degradation in the processing load because sentence resolution has been attempted around this site.
In the second experiment, an auditory moving window (AMW) task was adopted. The AMW technique is considered to be able to capture patterns of resource allocation during online linguistic processing and has been widely used in attempts to distinguish between the two competing WM approaches16,17. It is presumed that extrasentential interference should cost listeners extra time during the course of processing the transient upcoming spoken sentence. Under the AMW paradigm, the participants heard sentences that were segmented into words, and they pressed a key on the keyboard to initiate playing of the subsequent segment. Thus, the durations of the pauses between keypresses to initiate the subsequent segment and control the flow of incoming information reflect the participants&#8217; responsiveness to the particular linguistic features in question. For example, if the extrasentential interference has certain effects on processing sentences of differing syntactic complexity, participants will exhibit correspondingly longer pause durations before initiating the subsequent segments. The procedures are schematized and presented in Figure 2.
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/59660/59660fig02.jpg" /> 
Figure 2: Extrasentential interference procedure with a digit recall task. 
<a href="https://www.jove.com/files/ftp_upload/59660/59660fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
The following protocol shows how researchers use a visually presented lexical decision task as intrasentential interference and the concurrent arithmetic interference load as extrasentential interference to investigate WM involvement and the processing asymmetry of Chinese RCs and elaborate the underlying logic.

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			<td>Psychology Software Tools</td>
			<td>version Professional 2.0</td>
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			<td>Headphone</td>
			<td>Logitech</td>
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			<td>Praat</td>
			<td>Praat</td>
			<td>5.3.43</td>
			<td>The online software used to edit the sound files for listening; http://www.fon.hum.uva.nl/praat/</td>
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			<td>Serial Response Box</td>
			<td>Psychology Software Tools</td>
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			<td>Standard PC</td>
			<td>ASUS K42Jv laptop</td>
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examining online syntactic processing of spoken complex sentences in chinese using dual-modal interference tasks

Working memory (WM) plays a central role in the comprehension of complex sentences. Its function in the processing of spoken complex sentences is especially evident because spoken complex sentence processing is memory-intensive. The dual-modal interference paradigm has been used to examine how the WM system is involved in complex syntactic processing. This article presents two exemplar experiments involving auditory processing with either intra- or extrasentential interferences. In the first experiment, auditory stimuli [spoken-Chinese relative clause (RC) sentences with two syntactic types: subject-gapped (SRC) vs. object-gapped (ORC)] are interfered with via a visually presented lexical decision task within a sentence and manipulated using three different interference timepoints. In the second experiment, the same auditory stimuli, presented via an auditory window moving technique, are interfered with via a visually presented digital recall task beyond the sentence and manipulated using three digital memory loads. By assessing how the primary task of comprehending the RC sentences is affected by the secondary task, we can tackle the controversial issue concerning Chinese RC processing asymmetry. Our results reveal different patterns of RC processing compared to those reported in previous studies. Experiment 1 manifests no clear RC processing advantages in either SRC or ORC; however, a preference for ORC is observed at the ends of sentences, and a preference for SRC is found at the main verb site. Likewise, Experiment 2 presents a dynamic pattern. Under a no-digit load, SRCs show processing advantages in the RC marker region. However, under higher-digit-load interference, ORCs show processing advantages in the same region. These results lead to the conjecture that no obvious or intrinsic processing asymmetry exists in the processing of Chinese RCs. Using the approach of assessing specific interference during syntactic processing, these experiments demonstrate future research applications that explore the processing metrics of spoken sentences involving working memory.

The interference effect was observed in both the dual-modal intra-LDT and the extradigit load tasks. Considering the three probe sites in Experiment 1, the RT results of the intra-LDT task manifested a dynamic pattern of RC processing as a function of two RC types. As shown in Figure 3, the ORC type exhibits a processing advantage at the position post the matrix subject (SMC) after the RC (P1) and at the end of the sentence (P3), whereas the SRC type has an advantage at the positi...

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Examining Online Syntactic Processing of Spoken Complex Sentences in Chinese Using Dual-Modal Interference Tasks

Here, we present a protocol employing dual-modal interference tasks to examine online processing of spoken-Chinese relative clause sentences. Two exemplar experiments involving auditory processing with intra- and extrasentential interferences are described. The paradigm provides a methodology for addressing the nature of working memory and its effects on sentence processing.

Working memory (WM) plays a central role in the comprehension of complex sentences. Its function in the processing of spoken complex sentences is ...

examining-online-syntactic-processing-spoken-complex-sentences

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Behavior

5.5K Views.  National Tainan Junior College of Nursing. Here, we present a protocol employing dual-modal interference tasks to examine online processing of spoken-Chinese relative clause sentences. Two exemplar experiments involving auditory processing with intra- and extrasentential interferences are described. The paradigm provides a methodology for addressing the nature of working memory and its effects on sentence processing.

Video: Examining Online Syntactic Processing of Spoken Complex Sentences in Chinese Using Dual-Modal Interference Tasks

Automated Visual Cognitive Tasks for Recording Neural Activity Using a Floor Projection Maze

Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have developed visual cognitive tasks for rats using the Floor Projection Maze1,2&#160;that are optimized for visual abilities of rats permitting stronger comparisons of experimental findings with other species.
In order to investigate neural correlates of learning and memory, we have integrated electrophysiological recordings into fully automated cognitive tasks on the Floor Projection Maze1,2. Behavioral software interfaced with an animal tracking system allows monitoring of the animal's behavior with precise control of image presentation and reward contingencies for better trained animals. Integration with an in vivo electrophysiological recording system enables examination of behavioral correlates of neural activity at selected epochs of a given cognitive task.
We describe protocols for a model system that combines automated visual presentation of information to rodents and intracranial reward with electrophysiological approaches. Our model system offers a sophisticated set of tools as a framework for other cognitive tasks to better isolate and identify specific mechanisms contributing to particular cognitive processes.

We describe protocols for training rats for chronic electrophysiological recordings in fully automated cognitive tasks on a Floor Projection Maze.

Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have ...

Uncovering Beat Deafness: Detecting Rhythm Disorders with Synchronized Finger Tapping and Perceptual Timing Tasks

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here with the goal of uncovering rhythm disorders, such as beat deafness. Beat deafness is characterized by poor performance in perceiving durations in auditory rhythmic patterns or poor synchronization of movement with auditory rhythms (e.g., with musical beats). These tasks include the synchronization of finger tapping to the beat of simple and complex auditory stimuli and the detection of rhythmic irregularities (anisochrony detection task) embedded in the same stimuli. These tests, which are easy to administer, include an assessment of both perceptual and sensorimotor timing abilities under different conditions (e.g., beat rates and types of auditory material) and are based on the same auditory stimuli, ranging from a simple metronome to a complex musical excerpt. The analysis of synchronized tapping data is performed with circular statistics, which provide reliable measures of synchronization accuracy (e.g., the difference between the timing of the taps and the timing of the pacing stimuli) and consistency. Circular statistics on tapping data are particularly well-suited for detecting individual differences in the general population. Synchronized tapping and anisochrony detection are sensitive measures for identifying profiles of rhythm disorders and have been used with success to uncover cases of poor synchronization with spared perceptual timing. This systematic assessment of perceptual and sensorimotor timing can be extended to populations of patients with brain damage, neurodegenerative diseases (e.g., Parkinson&#8217;s disease), and developmental disorders (e.g., Attention Deficit Hyperactivity Disorder).

Behavioral tasks that allow for the assessment of perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) are presented. Synchronization of finger tapping to the beat of an auditory stimuli and detecting rhythmic irregularities provides a means of uncovering rhythm disorders.

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here ...

Performing Behavioral Tasks in Subjects with Intracranial Electrodes

Patients having stereo-electroencephalography (SEEG) electrode, subdural grid or depth electrode implants have a multitude of electrodes implanted in different areas of their brain for the localization of their seizure focus and eloquent areas. After implantation, the patient must remain in the hospital until the pathological area of brain is found and possibly resected. During this time, these patients offer a unique opportunity to the research community because any number of behavioral paradigms can be performed to uncover the neural correlates that guide behavior. Here we present a method for recording brain activity from intracranial implants as subjects perform a behavioral task designed to assess decision-making and reward encoding. All electrophysiological data from the intracranial electrodes are recorded during the behavioral task, allowing for the examination of the many brain areas involved in a single function at time scales relevant to behavior. Moreover, and unlike animal studies, human patients can learn a wide variety of behavioral tasks quickly, allowing for the ability to perform more than one task in the same subject or for performing controls. Despite the many advantages of this technique for understanding human brain function, there are also methodological limitations that we discuss, including environmental factors, analgesic effects, time constraints and recordings from diseased tissue. This method may be easily implemented by any institution that performs intracranial assessments; providing the opportunity to directly examine human brain function during behavior.

Patients implanted with intracranial electrodes provide a unique opportunity to record neurological data from multiple areas of the brain while the patient performs behavioral tasks. Here, we present a method of recording from implanted patients that can be reproducible at other institutions with access to this patient population.

Patients having stereo-electroencephalography (SEEG) electrode, subdural grid or depth electrode implants have a multitude of electrodes implanted in ...

Practical Methodology of Cognitive Tasks Within a Navigational Assessment

This paper describes an approach for measuring navigation accuracy relative to cognitive skills. The methodology behind the assessment will thus be clearly outlined in a step-by-step manner. Navigational skills are important when trying to find symbols within a speech-generating device (SGD) that has a dynamic screen and taxonomical organization. The following skills have been found to impact children&#8217;s ability to find symbols when navigating within the levels of an SGD: sustained attention, categorization, cognitive flexibility, and fluid reasoning1,2. According to past studies, working memory was not correlated with navigation1,2.
The materials needed for this method include a computerized tablet, an augmentative and alternative communication application, a booklet of symbols, and the Leiter International Performance Scale-Revised (Leiter-R)3. This method has been used in two previous studies. Robillard, Mayer-Crittenden, Roy-Charland, Minor-Corriveau and B&#233;langer1 assessed typically developing children, while Rondeau, Robillard and Roy-Charland2 assessed children and adolescents with a diagnosis of Autism Spectrum Disorder. The direct observation of this method will facilitate the replication of this study for researchers. It will also help clinicians that work with children who have complex communication needs to determine the children&#8217;s ability to navigate an SGD with taxonomical categorization.

Children who have complex communication needs can benefit from the use of a speech-generating device (SGD). Cognitive skills were identified as having an impact on the ability to navigate between levels of SGDs. This protocol describes the steps needed for Speech-language Pathologists to assess cognitive skills and navigational abilities.

This paper describes an approach for measuring navigation accuracy relative to cognitive skills. The methodology behind the assessment will thus be ...

Methods to Test Visual Attention Online

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative data samples than can typically be collected on college campuses. However, before such methods can be widely adopted, a number of technological challenges must be overcome &#8211; in particular in experiments where tight control over stimulus properties is necessary. Here we present methods for collecting performance data on two tests of visual attention. Both tests require control over the visual angle of the stimuli (which in turn requires knowledge of the viewing distance, monitor size, screen resolution, etc.) and the timing of the stimuli (as the tests involve either briefly flashed stimuli or stimuli that move at specific rates). Data collected on these tests from over 1,700 online participants were consistent with data collected in laboratory-based versions of the exact same tests. These results suggest that with proper care, timing/stimulus size dependent tasks can be deployed in web-based settings.

To replicate laboratory settings, online data collection methods for visual tasks require tight control over stimulus presentation. We outline methods for the use of a web application to collect performance data on two tests of visual attention.

Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative ...

Using Fiberless, Wearable fNIRS to Monitor Brain Activity in Real-world Cognitive Tasks

Functional Near Infrared Spectroscopy (fNIRS) is a neuroimaging technique that uses near-infrared light to monitor brain activity. Based on neurovascular coupling, fNIRS is able to measure the haemoglobin concentration changes secondary to neuronal activity. Compared to other neuroimaging techniques, fNIRS represents a good compromise in terms of spatial and temporal resolution. Moreover, it is portable, lightweight, less sensitive to motion artifacts and does not impose significant physical restraints. It is therefore appropriate to monitor a wide range of cognitive tasks (e.g., auditory, gait analysis, social interaction) and different age populations (e.g., new-borns, adults, elderly people). The recent development of fiberless fNIRS devices has opened the way to new applications in neuroscience research. This represents a unique opportunity to study functional activity during real-world tests, which can be more sensitive and accurate in assessing cognitive function and dysfunction than lab-based tests. This study explored the use of fiberless fNIRS to monitor brain activity during a real-world prospective memory task. This protocol is performed outside the lab and brain haemoglobin concentration changes are continuously measured over the prefrontal cortex while the subject walks around in order to accomplish several different tasks.

Monitoring brain activity outside the lab without physical constraints presents methodological challenges. A fiberless, wearable functional Near Infrared Spectroscopy (fNIRS) system was used to measure brain activity during an ecological prospective memory task. It was demonstrated that this system could be used to monitor brain activity during non-lab based experiments.

Functional Near Infrared Spectroscopy (fNIRS) is a neuroimaging technique that uses near-infrared light to monitor brain activity. Based on neurovascular ...

Examining Recall Memory in Infancy and Early Childhood Using the Elicited Imitation Paradigm

The ability to recall the past allows us to report on details of previous experiences, from the everyday to the significant. Because recall memory is commonly assessed using verbal report paradigms in adults, studying the development of this ability in preverbal infants and children proved challenging. Over the past 30 years, researchers have developed a non-verbal means of assessing recall memory known as the elicited or deferred imitation paradigm. In one variant of the procedure, participants are presented with novel three-dimensional stimuli for a brief baseline period before a researcher demonstrates a series of actions that culminate in an end- or goal-state. The participant is allowed to imitate the demonstrated actions immediately, after a delay, or both. Recall performance is then compared to baseline or to performance on novel control sequences presented at the same session; memory can be assessed for the individual target actions and the order in which they were completed. This procedure is an accepted analogue to the verbal report techniques used with adults, and it has served to establish a solid foundation of the nature of recall memory in infancy and early childhood. In addition, the elicited or deferred imitation procedure has been modified and adapted to answer questions relevant to other aspects of cognitive functioning. The broad utility and application of imitation paradigms is discussed, along with limitations of the approach and directions for future research.

The elicited imitation procedure was established to examine the development of recall memory in infancy and early childhood. This procedure has been widely used to establish a solid foundation of the nature of recall memory in infancy and early childhood.

The ability to recall the past allows us to report on details of previous experiences, from the everyday to the significant. Because recall memory is ...

Comparing the Frequency Effect Between the Lexical Decision and Naming Tasks in Chinese

In psycholinguistic research, the frequency effect can be one of the indicators for eligible experimental tasks that examine the nature of lexical access. Usually, only one of those tasks is chosen to examine lexical access in a study. Using two exemplar experiments, this paper introduces an approach to include both the lexical decision task and the naming task in a study. In the first experiment, the stimuli were Chinese characters with frequency and regularity manipulated. In the second experiment, the stimuli were switched to Chinese two-character words, in which the word frequency and the regularity of the leading character were manipulated. The logic of these two exemplar experiments was to explore some important issues such as the role of phonology on recognition by comparing the frequency effect between both the tasks. The results revealed different patterns of lexical access from those reported in the alphabetic systems. The results of Experiment 1 manifested a larger frequency effect in the naming task as compared to the LDT, when the stimuli were Chinese characters. And it is noteworthy that, in Experiment 1, when the stimuli were regular Chinese characters, the frequency effect observed in the naming task was roughly equivalent to that in the LDT. However, a smaller frequency effect was shown in the naming task as compared to the LDT, when the stimuli were switched to Chinese two-character words in Experiment 2. Taking advantage of the respective demands and characteristics in both tasks, researchers can obtain a more complete and precise picture of character/word recognition.

Researchers adopt both the lexical decision task and the naming task to investigate some important topics such as character/word recognition by comparing the frequency effect between these two tasks. This article introduces this approach through two exemplar experiments and elaborates on the underlying logic.

In psycholinguistic research, the frequency effect can be one of the indicators for eligible experimental tasks that examine the nature of lexical access. ...

A Method to Quantify Visual Information Processing in Children Using Eye Tracking

Visual problems that occur early in life can have major impact on a child's development. Without verbal communication and only based on observational methods, it is difficult to make a quantitative assessment of a child's visual problems. This limits accurate diagnostics in children under the age of 4 years and in children with intellectual disabilities. Here we describe a quantitative method that overcomes these problems. The method uses a remote eye tracker and a four choice preferential looking paradigm to measure eye movement responses to different visual stimuli. The child sits without head support in front of a monitor with integrated infrared cameras. In one of four monitor quadrants a visual stimulus is presented. Each stimulus has a specific visual modality with respect to the background, e.g., form, motion, contrast or color. From the reflexive eye movement responses to these specific visual modalities, output parameters such as reaction times, fixation accuracy and fixation duration are calculated to quantify a child's viewing behavior. With this approach, the quality of visual information processing can be assessed without the use of communication. By comparing results with reference values obtained in typically developing children from 0-12 years, the method provides a characterization of visual information processing in visually impaired children. The quantitative information provided by this method can be advantageous for the field of clinical visual assessment and rehabilitation in multiple ways. The parameter values provide a good basis to: (i) characterize early visual capacities and consequently to enable early interventions; (ii) compare risk groups and follow visual development over time; and (iii), construct an individual visual profile for each child.

A method is described to quantify the quality of visual information processing based on reflexive eye movements in response to specific visual modalities. Reaction times and fixation output parameters are used to characterize visual performance in children with and without visual impairments from 6 months of age.

Visual problems that occur early in life can have major impact on a child's development. Without verbal communication and only based on observational ...

Using Eye Movements Recorded in the Visual World Paradigm to Explore the Online Processing of Spoken Language

In a typical eye tracking study using the visual world paradigm, participants' eye movements to objects or pictures in the visual workspace are recorded via an eye tracker as the participant produces or comprehends a spoken language describing the concurrent visual world. This paradigm has high versatility, as it can be used in a wide range of populations, including those who cannot read and/or who cannot overtly give their behavioral responses, such as preliterate children, elderly adults, and patients. More importantly, the paradigm is extremely sensitive to fine grained manipulations of the speech signal, and it can be used to study the online processing of most topics in language comprehension at multiple levels, such as the fine grained acoustic phonetic features, the properties of words, and the linguistic structures. The protocol described in this article illustrates how a typical visual world eye tracking study is conducted, with an example showing how the online processing of some semantically complex statements can be explored with the visual world paradigm.

The visual world paradigm monitors participants' eye movements in the visual workspace as they are listening to or speaking a spoken language. This paradigm can be used to investigate the online processing of a wide range of psycholinguistic questions, including semantically complex statements, such as disjunctive statements.

In a typical eye tracking study using the visual world paradigm, participants' eye movements to objects or pictures in the visual workspace are recorded ...