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Abstract
An Aesthesiometer and Fechner’s Law of Limits were used to determine the two-point threshold of various parts of the anatomy. Statistical studies for ANOVA and Tukey’s HSD were done to analyze the data. Significant differences in two-point threshold of these parts of the anatomy were discovered, which is consistent with earlier studies. These results are important in the study of perception because they show the relation between various anatomical factors and tactile acuity.

 

 

 

 

Introduction

The study of tactile spatial acuity has a long and interesting history, beginning with Ernest Weber’s De Tactu (1834). The two-point test, or compass test, is the classic method of determining tactile acuity. Even though it has been repudiated in large measures by researchers (see Craig and Johnson, 2000), it still remains one of the more important tests for spatial sensitivity of the skin. This sensitivity depends on, among other factors, receptor field size, cell density (density of dermal mechanoreceptors) and area of projection to somatosensory cortex, etc.

The basic question addressed by this test was: How far apart should two separate points be for them to be perceived as two points rather than as one? The answer will vary with the area of the anatomy tested for an individual subject. The importance of analyzing this data lies in understanding the relative tactile sensitivity of different parts of the body, and the reasons for certain parts of the body being more sensitive than others. This test is often used in the medical field to assess nerve damage.

There are four nerves distributed in the arm, the posterior antebrachial cutaneous, the radial, the ulnar, and the median. Each covers a separate area of the skin, and is directly connected to various mechanoreceptors. There are various mechanoreceptors present in the skin of the arm. The Merkel’s disk and the Meissner’s corpuscle, which are small in size, respond to pressure and flutter respectively. The two large receptors, Ruffini’s corpuscle and Pacinian corpuscle, respond to stretch and vibration.

In this experiment, the hypothesis was that the threshold for the fingertips were the smallest of the four areas tested. Statistically, this implies that there are significant differences between the means of each group. This was verified by an ANOVA. A Tukey’s HSD was conducted as a post hoc measure to determine which of the means differed most significantly.

 

Method

Subjects: The subjects in this experiment were undergrad students enrolled in an Advanced Experimental Psychology course at CUNY. The age ranges were from between 20 to 40.

Experimental Design: A true experiment was conducted with one independent variable and one dependent variable. The independent variable was the anatomical testing location, which had four levels as follows:
1) The fingertip of the pointer finger of the dominant (writing) hand
2) The forearm on the same side.
3) The back of the palm on the same side
4) The inner palm on the same side

The dependent variable was the threshold of spatial resolution, that is, the two points between which the response of the subject changed from an “one” to a “two’ or vice versa.

Apparatus: An Aesthesiometer (or Esthesiometer) was the principal apparatus used. Also used were instruction sheets, rubbing alcohol and calculators.

Procedure:

Each subject’s thresholds were measured by another subject. The apparatus used was an Aesthesiometer. This is a compass-like instrument with two calipers used to measure tactile sensitivity. Every student had a chance to serve as a subject. The following points were adhered to:

1. When applying the tips of the Aesthesiometer to the subject’s skin, both tips were applied at the same time since otherwise the subject would have been able to differentiate the two locations based on time. The tips were applied lightly since repeated trials at the same location might have irritated the subject’s skin if one applied too much pressure.
2. The tips were applied as consistently as possible across trials.
3. The points were applied along the long axis of the finger and the forearm, etc. i.e. the line between the two points were parallel to the length of the finger and parallel to the length of the forearm etc.

                             
Before running practice trials, the experimenter tried the Aesthesiometer on herself to get an idea of how lightly to apply the points and to get some practice at applying the points simultaneously: The Aesthesiometer was held just behind the slider from the top. Then the experimenter closed her eyes, and tried a few different distances on her fingertip and inside of the forearm (halfway between the wrist and elbow). Once she was comfortable with applying the points, the practice trials were begun.

Practice trials

The subject was asked to rest the hand and forearm of his/her dominant side on the table, palm side up. The subject was asked close his/her eyes. The experimenter only touched the subject using the Aesthesiometer. She applied both tips of the Aesthesiometer simultaneously, and the subject was asked to indicate whether it felt like two points or just one.

Firstly, on the fingertip, a test was done on five random tip-distances with values chosen around 3 mm, some higher, some lower. Then five random tip-distances on the forearm were tested, but now values chosen were around 16 mm. Practice trials were conducted until both subject and experimenter became comfortable with the tasks.

Experimental trials

Fechner’s method of limits was used to obtain 2 thresholds for each subject: one for each of the four locations. The fingertips were tested first:

1. The descending series: The experiment started at 10 mm (=1 cm). After the subject responded (“two”), the distance was reduced 1 mm at a time until the subject said they perceived one point rather than two. Once they responded “one”, the present distance and the previously measured distance were marked in order to later compute, in step 4 below, the crossover point as the average of these two distances.
2. The ascending series: The next series started at 1 mm (=0.1 cm) and incremented 1 mm at a time until the subject responded by saying two points rather than one. Once they said “two”, the present distance and the previously measured distance were marked. Step 1 was repeated along with Step 2.
3. A total of 6 such measurements were made, 3 ascending, 3 descending, alternating.
4. The crossover point for each of the 6 series of trials was computed as an average of the 2 distances the experimenter marked down for each series, i.e. the distances between which the subject changed their response from “one” too “two” or vice versa.
5. Then the average of the 6 crossover values from Step 4 were computed. This is the subject’s 2-pt threshold for the fingertip.
6. Steps 1-5 were repeated for the remaining three areas in the body.  The starting point for the ascending and descending series were chosen as 3, 4, 16 and 40 mm.

Results
The following two tables represent the Mean, Standard deviation and ANOVA on the test data. As can be observed, there is wide divergence in both the mean and p-values of the ANOVA. This indicates that the fingertips have a much lower threshold for tactile acuity than the other measured parts of the body.

 

TABLE 1: MEAN AND SD

 

TABLE 2: F AND P VALUES OF ANOVA

Post hoc analyses using the Tukey HSD post hoc criterion for significance indicated that the average threshold for discriminating two-pts was significantly lower in the index finger (MD = 32.474, SED = 3.059) than in the forearm (p<0.05).

 

Discussion

The four means in table 1 can be grouped into two sets; set one consisting of the fingertips and the inner palm and the other set consisting of the outer palm and forearm. The first set has closely grouped values, implying that the tactile acuity of these two areas is almost equal. This amount diverges widely from the mean sensitivity of the other set, showing that the former areas are, in general, much more sensitive to tactile stimuli of the spatial resolution type than the latter. This means that the factors which increase tactile acuity are present in higher amounts in the fingertips, say, than in the forearm.

This is further demonstrated by the p-values of the ANOVA table, where we observe very significant results between the fingertips and the forearm. Tukey HSD also indicates that the average threshold for discriminating between two points was significantly lower in the fingertips than in the forearm.  This is consistent with previous studies.

There is some heterogeneity in data from fingertips in subject numbered ten and eleven, in subject eleven for inner palm, and wide divergences in the other two groups. This can be explained by subjective factors like methodological differences of execution, different subjects, different experimenters, etc. These are, indeed, some of the reasons why the Two-point test is disparaged by some researchers (see Craig and Johnson, 2000). This is also an incentive for us to repeat the experiment as many times as possible, in order to lower the threshold of subjective errors by basically increasing sample size over many experiments.

There are many ways in which this experiment could have been improved. The sampling could have been improved by taking subjects from a wider population, wider age groups etc. There was no counterbalancing the ascending/descending series, which could have definitely improved upon the design of the experiment. There was also no control for the sequencing and ordering of the body parts, which could conceivably have had some impact on outcomes. These are some of the improvements that could have been made to improve the experiment.

 

Conclusion

This experiment, which is a replication of the classic Two point threshold experiment, again consistently proved that the spatial resolution of the fingertips is much more acute than that of the forearm.

References:

1. James C. Craig; Kenneth O. Johnson, The Two-Point Threshold: Not a Measure of Tactile Spatial Resolution, Current Directions in Psychological Science, Volume 9, Number 1, February 2000 , pp. 29-32(4)

 

2. Shepherd, G.M. (1994). Neurobiology, Third ed. Oxford: Oxford University Press.

 

3. Bellamy, M.L. and Frame, K. (Eds.) (1996). Neuroscience Laboratory and Classroom Activities. National Association of Biology Teachers and the Society for Neuroscience, pp. 113-136.

 

4. Weber, EH. De subtilitate tactus (De tactu). In: Ross HE. , translator; Ross HE, Murray DJ. , editors. E. H. Weber on the Tactile Senses. 2nd ed. Hove, UK: Erlbaum Taylor and Francis; 1996. pp. 19–134. Original work published 1834.

 

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Politics in India

A Brief History:
India has been ruled by “foreigners” for over three thousand years, and the clashes and interactions between the rulers and the ruled, and the lessons each have learnt from the other, form the backdrop against which indigenous democracy in Modern India should be studied. Therefore, though a study of the history of politics in Modern India should technically begin with 15th August, 1947, when India overthrew British domination to take birth as an independent nation, the actual tendencies that persist in Indian politics even today can be traced back to the period of British rule and even further. Thus, to understand the politics of religion, one needs to understand the period of Muslim rule in India, and to appreciate the strange and ubiquitous caste-politics and the pressures it exerts on the Indian political system, one needs to go as far back as the Vedic ages, when the noble Aryans were ruling India from behind the fortress of the caste system. 
Politics in India has been shaped by the following factors :

• The British Legacy
• Religion
• Caste

The British ruled India for a period of ninety years, from 1857 – 1947. During that time, they brought together the various warring Indian provinces under a strong and central rule. They introduced some processes through which the Indians could get themselves elected to local bodies, which gave the latter some practice in self-government. From the British, the Indians also inherited a civil service, which had the expertise and training to take over the administrative functions of the new-born nation.

Religion and politics are closely inter-twined in India, and many historians locate the source of this relationship in the policy of ‘Divide and Rule’ introduced by the British in 1909. It was this policy that instigated the Partition of the country during the time of the Independence, and it is with a slightly altered version of this policy that the political parties still choose to sway the vote bank. The Congress has always tried to maintain a secular appearance; at the same time, it has also been castigated for pandering to the Muslims. The Bharatiya Janata Party has tried to mobilize the Hindus of the country with the slogan of Hindutva. Riots between the Hindus and the Muslims tear the country apart at regular intervals, and serve as a grim reminder of the nefarious connection between politics and religion.

Caste is another powerful weapon in the armory of the politicians. Caste is a hierarchical form of oppression, and since the Indian Constitution recognizes the stratification of the Indian society into castes, politicians have used it to mobilize various classes of people. Parties like the BSP and the RJD are the strongholds of particular castes. Unfortunately, after obtaining power, their leaders do everything they can to further their personal aims, and nothing to improve the lives of their people. Seat reservations and quotas for the people of socially backward classes and tribes have been adopted, but primarily for the purpose of political gains.   

Key Government Institutions:
The framers of the Indian Constitution chose the form of constitutional democracy for themselves, in accordance with the British model of government. In the Indian model, there is the President/Prime Minister duo, the Parliament, and the Supreme Court, that between themselves carry out executive, legislative and judiciary functions of the state respectively. There are two distinct heads in the system, the President and the Prime Minister. The latter is the elected head of the government, while the former is selected by elected representatives of the people.

The President is the titular head of the state of India.  In theory, the President enjoys considerable power; in practice, however, the council of elected ministers, headed by the Prime Minister, carries out executive, legislative, financial, judicial and emergency powers. The President is the Supreme Commander of the Indian armed forces. She or he has the right to appoint the Prime Minister of the country, and the members of the Council of Ministers, the Governors of States, the judges of the Supreme and High Courts, etc. However, in all these cases, the President is bound by the constitution to follow the advice of the Prime Minister.  The President of India is therefore only a formal and constitutional head and does not have any real power.

The real executive power lies with the Prime Minister who is the administrative head of the state. While the President is the nominal leader of the country, the Prime Minister of India is the leader of the government; the de facto person in power that runs the government. He or she is generally the leader of the majority party in the Lok Sabha, or Lower House of the Parliament. Every five years, national elections are held all over India to elect a party to the government. Usually a party puts up a prime ministerial candidate before the election. But this is not always so, and is not mandatory. For example, before the 2004 election, the Congress party implicitly focused on Sonia Gandhi, the leader of the Congress party and an Italian by birth, as the prime ministerial candidate. But post election, Manmohan Singh was made the Prime Minister, because it was perceived that the country was not ready for a foreign-born Prime Minister. The Prime Minister heads the Council of Ministers, and, in that capacity, is in charge of supervising the work of all the ministers. It is mandatory to refer matters such as defense, judicial and diplomatic appointments, all policy and administrative issues to the Prime Minister for her or his consideration.

Election in India follows the British system of first-past-the-post or FPTP. In this system, the candidate with the highest number of votes wins. There is no necessity to reach a majority in this system. In India, the effect of this system is seen in the very small margin with which some Prime Ministers have been elected. The downside of this system is that smaller, regional  parties tend to have undeserved power. For example, Trinamool and AIDMK, two regional parties from Bengal and Tamil Nadu respectively, gained enormous power in the last election because Congress got elected by a small margin only through their support. The result is that these regional parties tend to uphold their own regional agendas over the greater good of the nation, and the resultant coalition government becomes a messy affair. Following Duverger’s law , however, such systems tend to turn into bipartite system in the long run, which removes this particular evil.

The Prime Minister enjoys many powers, but is always answerable to the Parliament. The Parliament is a legislative body composed of two houses, the Rajya Sabha or the upper house, comprising of 250 members, and the Lok Sabha or the lower house comprising of 543 members. The members of the Rajya Sabha are elected by the members of the state legislatures. The members of the Lok Sabha, along with the Prime Minister, are elected by the direct vote of the people. The Lok Sabha is a more powerful body than the Rajya Sabha. The Prime Minister and the Council of Ministers are answerable to and responsible to only the Lok Sabha. Money bills can only be introduced in the Lok Sabha. The Rajya Sabha does not have the right to refuse its consent to a money bill. Similarly, the budget needs to be approved only in the Lok Sabha.

The Parliament is the supreme legislative body of India. Together, its two Houses, the Rajya Sabha and the Lok Sabha, perform all kinds of legislative functions. They supervise and control the administrative functions of the country and they pass the budget. All bills, in order to become laws, have to be passed in both house of Parliament. The Parliament also has the power to suggest amendments to the Constitution. They are the body before which public grievances are aired and where issues of national and international importance are debated. The Parliament also has the power to impeach the President and other key government officials like the judges of the Supreme and the High Courts, the Election Commissioner, etc.

The Indian Constitution envisages a clear distinction of the legislative, the executive and the judicial powers of the state. The legislative powers are vested in the Parliament, the executive powers are vested in the Prime Minister and the Council of Ministers, while the judicial powers are vested in the Supreme Court and the high courts and the lower courts that are under its jurisdiction.

The Supreme Court is the highest judicial body in India. The Constitution of India has stated that the Supreme Court is a federal court; it is a guardian of the Constitution; and it is the highest court of appeal. The Supreme Court enjoys original jurisdiction in any dispute between the federal and the state governments, or any two state governments. It also enjoys original jurisdiction when the Fundamental Rights guaranteed by the Indian Constitution are violated. The Supreme Court enjoys appellate jurisdiction in the sense that it takes up appeals against the judgments of the High Courts. The President may ask the Supreme Court for its recommendations on certain matters, and that allows the Supreme Court to exercise advisory jurisdiction.   

The Nature of the Indian Political Culture :
The factors referred to in the introduction have combined to create a political culture that is unique to India.

The political culture of India is firstly marked by the ideals that the founders of India engraved in the Preamble to the Constitution of India. The Preamble seeks to establish India as a ‘sovereign, socialist, secular, democratic, republic.’ The traditions of sovereignty and republic are guaranteed by the Constitution in the sense that they are givens; there is no need to strive towards them. However, the traditions of socialism, secularism and democracy are things that the people of the country have to work to attain and maintain.

When one refers to India as a socialist democracy, one means that

• the government of India is directly elected by the people and
• it works to change and improve the condition of the people.

In order to uphold the socialist tradition, the Constitution of India earmarks certain provisions, known as the Directive Principles of State Policy. Some of the principles state that equal pay should be provided for equal work to men and women, children under the age of 14 should not be allowed to work in hazardous places, primary education should be compulsory for all, protection should be extended to historical monuments and the natural environment, etc. A few of these Directive Principles have been implemented, for example, the one providing free and compulsory education to all children under the age of 14, the one that ensure minimum wages to prevent the exploitation of workers, but most of them still lie in the sphere of visions.

There is no doubt about the fact that India is a functioning democracy. Elections are held at the national, state at local levels at regular intervals. To a large extent, they are free, fair and impartial. At the same time, there are a few ways in which the way the Indian electorate behaves that sets it apart from the rest of the world. In India it is the lower castes, the poor, the illiterate and the rural population that cast votes in larger numbers than their upper class, poor, literate, urban counterparts. This looks good on the outside, but the downside is that an illiterate electorate is easier to influence and to usurp, and political parties are not against taking advantage of this situation.

The attitude of the common Indians towards their political representatives is marked by growing suspicion. They are demanding greater accountability and a reformation of the electoral process. Thousands of NGOs and citizens's groups came together before the 2009 elections to vocalize the following demands:

• Bar candidates with criminal charges
• Introduce a 'none of the above option' in the ballot paper so that the voters can register their doubts about the unsuitability of the candidates
• Strive for greater transparency
• Regulate the funding of political parties.

Strangely enough, the Indian Constitution does not allow those awaiting trial to vote but does not bar people facing criminal charges from contesting in elections. This has allowed a situation whereby almost 50% of the Lok Sabha candidates have criminal records. The High Court has provided a positive outlook by ruling that candidates with criminal records and undergoing imprisonment cannot contest elections. The debate on this unsavory aspect of Indian politics seems destined to continue because of the mild or non-committal response from most political parties.

Patterns of Interaction:
Politics in India is undergoing changes in many other ways. The Congress is no longer the party of the majority. The country is now witnessing the sway of coalition politics. Most of the registered parties of the country (there are hundreds of political parties registered in India; of them, seven are registered as national parties, and approximately 43 of them have representatives in the Lok Sabha) have gathered under the banner of either the Congress or the Bharatiya Janata Party. The Communist Party of India, after breaking away from the Congress-coalition as a result of disagreement over the Indo-U.S. Nuclear Deal, is currently operating on its own.

There was a time in the early days of the Indian democracy when India was almost a single-party democracy, if that is not an oxymoron. The Congress party alone held sway, and except for a few regional parties, there was literally no opposition party in the system. That has changed in the last 25 years, with the rise of the Hindu nationalist BJP , and the emergence of the Communist Party as a more-than-regional player in the political milieu of India. From time to time and from election year to election year, other regional parties arise and become king-makers; the AIDMK, the RJD and other names come to mind. But these are basically regional parties; the three parties mentioned earlier are the only three parties that can rightly be called national parties.

Opposition works in peculiar oriental fashion, with modern avatars of erstwhile palace intrigues and factionalisms. Issues become paramount not by themselves, but because every issue can have distinct and conflicting sides. It is not solving an issue that is important, but to take sides that are different from the party in power and thereby proclaim ones existence. This peculiar defensive opposition mechanism may be traced back to the longterm sway of the Congress party, which made the other, smaller parties want to differentiate themselves from the behemoth and gain some recognition. This trend, one hopes, will discontinue when even smaller parties have proven to themselves and to the people that they too can win elections and form governments.

Citizen-speak: What do Indians argue about as a nation?

Public debate and intellectual pluralism are the hallmarks of Indian culture. The Nobel Prize winning economist Amartya Sen has brilliantly showcased the Indian addiction to contention and disputes in his book The Argumentative Indian. In his analysis, democracy has flourished in India because debate and skepticism are an integral part of the Indian national temper .

Some of the hotly debated topics of the moment among Indians are the country’s relations with Pakistan; corruption in politics and the ascending role played by the sons and daughters of renowned politicians in Indian politics; the Indo-US nuclear deal; and the meltdown of the US economy and its effect on India.

The country’s relations with Pakistan have always been a source of angst for the ordinary Indian. The Himalayan state of Kashmir has been the bone of contention ever since Independence, and Indians accuse Pakistanis of sheltering and training terrorists to attack India. The Mumbai-terrorist attacks of November 2008 have further exacerbated matters. The rampage that began on November 26, 2008, lasted for three days, and led to the deaths of 173 persons. Today, Indians believe that Pakistan will never fulfill the promise it made at the SAARC summit of 2007 to dismantle the training camps for terrorists in its country. They feel that the Pakistanis have betrayed them again and again (infiltration by the Pakistan troops in 1965, skirmishes during the 1980s in the Siachen glacier, violation of the Line-Of-Control in 1999). Their angst has deepened to the extent that, today, most Indians would gladly approve of a military excursion into Pakistan.

With its large middle-class population, Indians must always keep a vigilant eye on the economy. The condition is particularly critical at this moment because of the meltdown of the US financial system. India has not been directly hit by the sub-prime crisis. However, Obama’s pronouncements on outsourcing has threatened to shake the financial security of an emerging upper-middle class, whose dreams of luxury are financed by the lucrative salaries they earn from MNCs that have either opened offices in India or have outsourced part of their operations to India.  To make matters worse, inflation has soared to 11.4%, interest rates are rising and there are large government deficits. Economic growth is expected to slow to 7%. At the same time, the Indians are reluctant to allow their government to adopt the necessary measures like cutting subsidies. This is one topic of discussion that seems to lead the Indian nowhere because he or she cannot strike a balance between his or her needs and the needs of the country.

The overwhelming presence of the scions of the prominent political families of India in the Parliament is currently drawing the attention of the Indian public. The Gandhi-Nehru family is the begetter of this tradition: Jawaharlal Nehru, his daughter Indira Gandhi and his grandson Rajiv Gandhi have served as Prime Ministers to the country. Today many people forecast that Rajiv’s son Rahul is being groomed for the post of Prime Minister. Another Gandhi descendant serving in the Parliament is Varun Gandhi, son of Sanjay Gandhi and grandson of Indira Gandhi. He, however, belongs to the BJP, which is the Opposition party. Jyotiraditya Scindia is the third-generation of Scindias to participate in politics after his grandmother Vijayraje Scindia and his father, the late Madhavrao Scindia. Omar Abdullah’s family has dominated Kashmiri politics from the beginning: his grandfather played an important role in the accession of Kashmir to India and his father was the Chief Minister of Kashmir for a long period.  Politics has therefore taken on the form of a family business. Many Indians are apprehensive that democracy itself is being adversely affected by this tendency to defer to family name, and the appurtenances of power and wealth. They fear that this system is crowding out the grassroots political workers who have only their individual qualities and their mettle to thrust them forward.

Conclusion:

India is one of the most important experiments in democracy, where a motley crowd of languages, regions, factions, religions, castes and colors have been brought under the rule of one single Constitution that itself is a heady mixture of constitutions and political ideologues from around the world. It is a wonder of democracy that something as diverse as an ancient and non-unified country like India can be effectively run under one law, one government, and one system.

 

References

• Politics in India, Rajni Kothari, Orient Longman Limited (2003), Delhi
• India: Governing and Politics in a Developing Nation, R.L. Hardgrave, S.A. Kochanek, Wadsworth Publishing; 6 edition (August 4, 1999), United States
• The Politics of India since Independence, P.R. Brass, G. Johnson, Cambridge University Press; 2 edition (January 12, 2008), Canmbridge
• The Success of India’s Democracy,  Ed., Atul Kohli, Cambridge University Press (September 10, 2001), Cambridge
• Introduction to the Constitution of India, D.D. Basu, South Asia Books; Tenth edition (February 1984), India
• Caste in Indian Politics, Rajni Kothari, Asia Book Corporation of America (October 1973), USA
• Outsourcing to India (Chapter 3: Contemporary Indian Politics), Mark Kobayashi-Hillary, Springer; Berlin, Heidelberg, 2nd edition (April 19, 2005)
• The Argumentative Indian, Amartya Sen, Farrar, Straus and Giroux, United States, 2005
• Maurice Duverger, "Factors in a Two-Party and Multiparty System," in Party Politics and Pressure Groups (New York: Thomas Y. Crowell, 1972).

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